91 civic - tough question about cooling
 

first i'd like to say thanks to the great people on this forum for all
the help they provide.

i've done a search for my problem and i've found some things but
nothing exactly fits.

i recently performed a head gasket job on my civic. i began this job
because i had bubbling in my coolant resevoir after driving for a
while. i also had some electrical issues, but i don't see those as
related to the bubbles. the bubbling was not boiling. some kind of
gas was pushing through to the resevoir, and i assumed it was
compressed gases of some kind coming from the cyclinders through the
head gasket.

after removing the head, i took it to the shop. they told me the head
had to be machined by 6 thousands to remove the warp, which seems like
quite a bit. he also pointed out where the likely breaches of the old
gasket were.

i cleaned and lapped the surface of the block. there was no apparent
cracking or warping (i checked for warp with a quality straight edge in
multiple directions).

put everything back together to spec.

i filled up the cooling system, on an incline with the radiator high.
bled the system according to haynes.

i've been test driving it for several days, and what happens is a
little weird. after a light drive, i get a few minutes of bubbles
(again, not boiling - bubbles) and i can hear coolant sucking past the
rad cap in pulses. after a heavy drive i get the coolant pulsing, but
much more bubbling - like the bubbling i used to get.

the only thing i have found that i didn't do was crank on the heater
when i was filling the cooling system. is it possible that since i did
not do this, there was a chunk of air in the heater core that is now
escaping when the car heats up? i ran the car tonight at idle with the
heater on full blast after discovering this possibility, but the rad
stayed full (again on an incline) even with the bleeder open.

it seems there are three or four possibilities:
1 - block is cracked
2 - head is cracked and crack missed by shop
3 - heater core had air bubble and now air is working out
4 - head gasket was installed improperly

any thoughts? thanks.

Re: 91 civic - tough question about cooling
 

larson.joshua@gmail.com wrote:
> first i'd like to say thanks to the great people on this forum for all
> the help they provide.
>
> i've done a search for my problem and i've found some things but
> nothing exactly fits.
>
> i recently performed a head gasket job on my civic. i began this job
> because i had bubbling in my coolant resevoir after driving for a
> while. i also had some electrical issues, but i don't see those as
> related to the bubbles. the bubbling was not boiling. some kind of
> gas was pushing through to the resevoir, and i assumed it was
> compressed gases of some kind coming from the cyclinders through the
> head gasket.
>
> after removing the head, i took it to the shop. they told me the head
> had to be machined by 6 thousands to remove the warp, which seems like
> quite a bit. he also pointed out where the likely breaches of the old
> gasket were.
>
> i cleaned and lapped the surface of the block.

how exactly did you do this?

> there was no apparent
> cracking or warping (i checked for warp with a quality straight edge in
> multiple directions).
>
> put everything back together to spec.
>
> i filled up the cooling system, on an incline with the radiator high.
> bled the system according to haynes.
>
> i've been test driving it for several days, and what happens is a
> little weird. after a light drive, i get a few minutes of bubbles
> (again, not boiling - bubbles) and i can hear coolant sucking past the
> rad cap in pulses. after a heavy drive i get the coolant pulsing, but
> much more bubbling - like the bubbling i used to get.
>
> the only thing i have found that i didn't do was crank on the heater
> when i was filling the cooling system. is it possible that since i did
> not do this, there was a chunk of air in the heater core that is now
> escaping when the car heats up? i ran the car tonight at idle with the
> heater on full blast after discovering this possibility, but the rad
> stayed full (again on an incline) even with the bleeder open.
>
> it seems there are three or four possibilities:
> 1 - block is cracked
> 2 - head is cracked and crack missed by shop
> 3 - heater core had air bubble and now air is working out
> 4 - head gasket was installed improperly
>
> any thoughts? thanks.
>
the head could be cracked, but honda aren't renowned for this kind of
problem. much more likely imo, is that the cleaning/machining/lapping
process has left marks in the head surface that make it impossible for a
gas seal to be made.

either way, i think chasing down the problem is a bit academic at this
point. the cost of diagnostics on the head to see if it really is
cracked, labor, etc. just doesn't compare favorably with getting a "new"
jdm engine from japan for $290 plus shipping. if the motor was rare and
much more expensive, sure, chase the problem down, but it's not, so at
this point, i'd just swap it out and be done with it. [replacement also
eliminates the longevity issues associated with all the crud that
inevitably gets into the engine when the head comes off.]

Re: 91 civic - tough question about cooling
 

larson.joshua@gmail.com wrote:
> first i'd like to say thanks to the great people on this forum for all
> the help they provide.
>
> i've done a search for my problem and i've found some things but
> nothing exactly fits.
>
> i recently performed a head gasket job on my civic. i began this job
> because i had bubbling in my coolant resevoir after driving for a
> while. i also had some electrical issues, but i don't see those as
> related to the bubbles. the bubbling was not boiling. some kind of
> gas was pushing through to the resevoir, and i assumed it was
> compressed gases of some kind coming from the cyclinders through the
> head gasket.
>
> after removing the head, i took it to the shop. they told me the head
> had to be machined by 6 thousands to remove the warp, which seems like
> quite a bit. he also pointed out where the likely breaches of the old
> gasket were.
>
> i cleaned and lapped the surface of the block.

how exactly did you do this?

> there was no apparent
> cracking or warping (i checked for warp with a quality straight edge in
> multiple directions).
>
> put everything back together to spec.
>
> i filled up the cooling system, on an incline with the radiator high.
> bled the system according to haynes.
>
> i've been test driving it for several days, and what happens is a
> little weird. after a light drive, i get a few minutes of bubbles
> (again, not boiling - bubbles) and i can hear coolant sucking past the
> rad cap in pulses. after a heavy drive i get the coolant pulsing, but
> much more bubbling - like the bubbling i used to get.
>
> the only thing i have found that i didn't do was crank on the heater
> when i was filling the cooling system. is it possible that since i did
> not do this, there was a chunk of air in the heater core that is now
> escaping when the car heats up? i ran the car tonight at idle with the
> heater on full blast after discovering this possibility, but the rad
> stayed full (again on an incline) even with the bleeder open.
>
> it seems there are three or four possibilities:
> 1 - block is cracked
> 2 - head is cracked and crack missed by shop
> 3 - heater core had air bubble and now air is working out
> 4 - head gasket was installed improperly
>
> any thoughts? thanks.
>
the head could be cracked, but honda aren't renowned for this kind of
problem. much more likely imo, is that the cleaning/machining/lapping
process has left marks in the head surface that make it impossible for a
gas seal to be made.

either way, i think chasing down the problem is a bit academic at this
point. the cost of diagnostics on the head to see if it really is
cracked, labor, etc. just doesn't compare favorably with getting a "new"
jdm engine from japan for $290 plus shipping. if the motor was rare and
much more expensive, sure, chase the problem down, but it's not, so at
this point, i'd just swap it out and be done with it. [replacement also
eliminates the longevity issues associated with all the crud that
inevitably gets into the engine when the head comes off.]

Re: 91 civic - tough question about cooling
 

larson.joshua@gmail.com wrote:
> first i'd like to say thanks to the great people on this forum for all
> the help they provide.
>
> i've done a search for my problem and i've found some things but
> nothing exactly fits.
>
> i recently performed a head gasket job on my civic. i began this job
> because i had bubbling in my coolant resevoir after driving for a
> while. i also had some electrical issues, but i don't see those as
> related to the bubbles. the bubbling was not boiling. some kind of
> gas was pushing through to the resevoir, and i assumed it was
> compressed gases of some kind coming from the cyclinders through the
> head gasket.
>
> after removing the head, i took it to the shop. they told me the head
> had to be machined by 6 thousands to remove the warp, which seems like
> quite a bit. he also pointed out where the likely breaches of the old
> gasket were.
>
> i cleaned and lapped the surface of the block.

how exactly did you do this?

> there was no apparent
> cracking or warping (i checked for warp with a quality straight edge in
> multiple directions).
>
> put everything back together to spec.
>
> i filled up the cooling system, on an incline with the radiator high.
> bled the system according to haynes.
>
> i've been test driving it for several days, and what happens is a
> little weird. after a light drive, i get a few minutes of bubbles
> (again, not boiling - bubbles) and i can hear coolant sucking past the
> rad cap in pulses. after a heavy drive i get the coolant pulsing, but
> much more bubbling - like the bubbling i used to get.
>
> the only thing i have found that i didn't do was crank on the heater
> when i was filling the cooling system. is it possible that since i did
> not do this, there was a chunk of air in the heater core that is now
> escaping when the car heats up? i ran the car tonight at idle with the
> heater on full blast after discovering this possibility, but the rad
> stayed full (again on an incline) even with the bleeder open.
>
> it seems there are three or four possibilities:
> 1 - block is cracked
> 2 - head is cracked and crack missed by shop
> 3 - heater core had air bubble and now air is working out
> 4 - head gasket was installed improperly
>
> any thoughts? thanks.
>
the head could be cracked, but honda aren't renowned for this kind of
problem. much more likely imo, is that the cleaning/machining/lapping
process has left marks in the head surface that make it impossible for a
gas seal to be made.

either way, i think chasing down the problem is a bit academic at this
point. the cost of diagnostics on the head to see if it really is
cracked, labor, etc. just doesn't compare favorably with getting a "new"
jdm engine from japan for $290 plus shipping. if the motor was rare and
much more expensive, sure, chase the problem down, but it's not, so at
this point, i'd just swap it out and be done with it. [replacement also
eliminates the longevity issues associated with all the crud that
inevitably gets into the engine when the head comes off.]

Re: 91 civic - tough question about cooling
 

> > i cleaned and lapped the surface of the block.
>
> how exactly did you do this?

i scraped the block surface with a plastic scraper at first. then i
used carb cleaner and a toothbrush to scrub off the remaining gasket
crud. after it was fairly clean i used 600 grit sandpaper tightly
stapled to an index card sized piece of flat particle board. i lightly
sanded the surface.

> the head could be cracked, but honda aren't renowned for this kind of
> problem. much more likely imo, is that the cleaning/machining/lapping
> process has left marks in the head surface that make it impossible for a
> gas seal to be made.

the head surface seemed near perfect after being machined. there were
no scrapes/scratches of much significance on the block that i could
tell, but who knows. what do you mean by "impossible for a gas seal to
be made?"

> either way, i think chasing down the problem is a bit academic at this
> point. the cost of diagnostics on the head to see if it really is
> cracked, labor, etc. just doesn't compare favorably with getting a "new"
> jdm engine from japan for $290 plus shipping.

if this becomes the route i decide to take, where do you recommend
purchasing a "new jdm engine" (what does jdm mean - i thought the
engine code was DB-13 or something).

thanks!

Re: 91 civic - tough question about cooling
 

> > i cleaned and lapped the surface of the block.
>
> how exactly did you do this?

i scraped the block surface with a plastic scraper at first. then i
used carb cleaner and a toothbrush to scrub off the remaining gasket
crud. after it was fairly clean i used 600 grit sandpaper tightly
stapled to an index card sized piece of flat particle board. i lightly
sanded the surface.

> the head could be cracked, but honda aren't renowned for this kind of
> problem. much more likely imo, is that the cleaning/machining/lapping
> process has left marks in the head surface that make it impossible for a
> gas seal to be made.

the head surface seemed near perfect after being machined. there were
no scrapes/scratches of much significance on the block that i could
tell, but who knows. what do you mean by "impossible for a gas seal to
be made?"

> either way, i think chasing down the problem is a bit academic at this
> point. the cost of diagnostics on the head to see if it really is
> cracked, labor, etc. just doesn't compare favorably with getting a "new"
> jdm engine from japan for $290 plus shipping.

if this becomes the route i decide to take, where do you recommend
purchasing a "new jdm engine" (what does jdm mean - i thought the
engine code was DB-13 or something).

thanks!

Re: 91 civic - tough question about cooling
 

> > i cleaned and lapped the surface of the block.
>
> how exactly did you do this?

i scraped the block surface with a plastic scraper at first. then i
used carb cleaner and a toothbrush to scrub off the remaining gasket
crud. after it was fairly clean i used 600 grit sandpaper tightly
stapled to an index card sized piece of flat particle board. i lightly
sanded the surface.

> the head could be cracked, but honda aren't renowned for this kind of
> problem. much more likely imo, is that the cleaning/machining/lapping
> process has left marks in the head surface that make it impossible for a
> gas seal to be made.

the head surface seemed near perfect after being machined. there were
no scrapes/scratches of much significance on the block that i could
tell, but who knows. what do you mean by "impossible for a gas seal to
be made?"

> either way, i think chasing down the problem is a bit academic at this
> point. the cost of diagnostics on the head to see if it really is
> cracked, labor, etc. just doesn't compare favorably with getting a "new"
> jdm engine from japan for $290 plus shipping.

if this becomes the route i decide to take, where do you recommend
purchasing a "new jdm engine" (what does jdm mean - i thought the
engine code was DB-13 or something).

thanks!

Re: 91 civic - tough question about cooling
 

larson.joshua@gmail.com wrote:
>>>i cleaned and lapped the surface of the block.
>>
>>how exactly did you do this?
>
>
> i scraped the block surface with a plastic scraper at first. then i
> used carb cleaner and a toothbrush to scrub off the remaining gasket
> crud. after it was fairly clean i used 600 grit sandpaper tightly
> stapled to an index card sized piece of flat particle board. i lightly
> sanded the surface.

ok. unfortunately, the backing block you need for this kind of
operation needs to relatively large, very flat, and as rigid as
possible. last time i did this, i used a 6" x 8" chunk of 20mm glass i
got for free from a glass shop - it was in their scrap bin. much less
and small local distortion of the backing block means you can get excess
material removed from the "thin" sections, i.e. between pistons, and
almost nothing from the thick sections. unfortunately, the thin bits
are the worst possible place to remove excess as they're needed for sealing.

>
>
>>the head could be cracked, but honda aren't renowned for this kind of
>>problem. much more likely imo, is that the cleaning/machining/lapping
>>process has left marks in the head surface that make it impossible for a
>>gas seal to be made.
>
>
> the head surface seemed near perfect after being machined. there were
> no scrapes/scratches of much significance on the block that i could
> tell, but who knows. what do you mean by "impossible for a gas seal to
> be made?"

original surface on these things is near mirror. that way, there's no
small grooves for gas to leak along. if the head was machined on a
traditional milling machine, particularly this alloy head, it's /very/
hard to do without leaving scoring marks in it. last time i had to lap
a head was to cut out the grooves from a bad machining job where the
cutting die was picking up excess material on each pass of an exterior
edge, then dragging that chunk across the rest of the head leaving gouge
marks.

>
>
>>either way, i think chasing down the problem is a bit academic at this
>>point. the cost of diagnostics on the head to see if it really is
>>cracked, labor, etc. just doesn't compare favorably with getting a "new"
>>jdm engine from japan for $290 plus shipping.
>
>
> if this becomes the route i decide to take, where do you recommend
> purchasing a "new jdm engine" (what does jdm mean - i thought the
> engine code was DB-13 or something).

"jdm" is "japanese domestic market". due to tax and emissions laws in
japan, cars usually get junked with only 60k miles on them. that makes
them great for import to the u.s. where these engines still have loads
of useful life.

there's loads of places on the net advertising these kinds of motors,
and i don't endorse any particular one, but something like the site
below is worth investigation:

http://home.pacbell.net/timwang1/38021.html

>
> thanks!
>

Re: 91 civic - tough question about cooling
 

larson.joshua@gmail.com wrote:
>>>i cleaned and lapped the surface of the block.
>>
>>how exactly did you do this?
>
>
> i scraped the block surface with a plastic scraper at first. then i
> used carb cleaner and a toothbrush to scrub off the remaining gasket
> crud. after it was fairly clean i used 600 grit sandpaper tightly
> stapled to an index card sized piece of flat particle board. i lightly
> sanded the surface.

ok. unfortunately, the backing block you need for this kind of
operation needs to relatively large, very flat, and as rigid as
possible. last time i did this, i used a 6" x 8" chunk of 20mm glass i
got for free from a glass shop - it was in their scrap bin. much less
and small local distortion of the backing block means you can get excess
material removed from the "thin" sections, i.e. between pistons, and
almost nothing from the thick sections. unfortunately, the thin bits
are the worst possible place to remove excess as they're needed for sealing.

>
>
>>the head could be cracked, but honda aren't renowned for this kind of
>>problem. much more likely imo, is that the cleaning/machining/lapping
>>process has left marks in the head surface that make it impossible for a
>>gas seal to be made.
>
>
> the head surface seemed near perfect after being machined. there were
> no scrapes/scratches of much significance on the block that i could
> tell, but who knows. what do you mean by "impossible for a gas seal to
> be made?"

original surface on these things is near mirror. that way, there's no
small grooves for gas to leak along. if the head was machined on a
traditional milling machine, particularly this alloy head, it's /very/
hard to do without leaving scoring marks in it. last time i had to lap
a head was to cut out the grooves from a bad machining job where the
cutting die was picking up excess material on each pass of an exterior
edge, then dragging that chunk across the rest of the head leaving gouge
marks.

>
>
>>either way, i think chasing down the problem is a bit academic at this
>>point. the cost of diagnostics on the head to see if it really is
>>cracked, labor, etc. just doesn't compare favorably with getting a "new"
>>jdm engine from japan for $290 plus shipping.
>
>
> if this becomes the route i decide to take, where do you recommend
> purchasing a "new jdm engine" (what does jdm mean - i thought the
> engine code was DB-13 or something).

"jdm" is "japanese domestic market". due to tax and emissions laws in
japan, cars usually get junked with only 60k miles on them. that makes
them great for import to the u.s. where these engines still have loads
of useful life.

there's loads of places on the net advertising these kinds of motors,
and i don't endorse any particular one, but something like the site
below is worth investigation:

http://home.pacbell.net/timwang1/38021.html

>
> thanks!
>

Re: 91 civic - tough question about cooling
 

larson.joshua@gmail.com wrote:
>>>i cleaned and lapped the surface of the block.
>>
>>how exactly did you do this?
>
>
> i scraped the block surface with a plastic scraper at first. then i
> used carb cleaner and a toothbrush to scrub off the remaining gasket
> crud. after it was fairly clean i used 600 grit sandpaper tightly
> stapled to an index card sized piece of flat particle board. i lightly
> sanded the surface.

ok. unfortunately, the backing block you need for this kind of
operation needs to relatively large, very flat, and as rigid as
possible. last time i did this, i used a 6" x 8" chunk of 20mm glass i
got for free from a glass shop - it was in their scrap bin. much less
and small local distortion of the backing block means you can get excess
material removed from the "thin" sections, i.e. between pistons, and
almost nothing from the thick sections. unfortunately, the thin bits
are the worst possible place to remove excess as they're needed for sealing.

>
>
>>the head could be cracked, but honda aren't renowned for this kind of
>>problem. much more likely imo, is that the cleaning/machining/lapping
>>process has left marks in the head surface that make it impossible for a
>>gas seal to be made.
>
>
> the head surface seemed near perfect after being machined. there were
> no scrapes/scratches of much significance on the block that i could
> tell, but who knows. what do you mean by "impossible for a gas seal to
> be made?"

original surface on these things is near mirror. that way, there's no
small grooves for gas to leak along. if the head was machined on a
traditional milling machine, particularly this alloy head, it's /very/
hard to do without leaving scoring marks in it. last time i had to lap
a head was to cut out the grooves from a bad machining job where the
cutting die was picking up excess material on each pass of an exterior
edge, then dragging that chunk across the rest of the head leaving gouge
marks.

>
>
>>either way, i think chasing down the problem is a bit academic at this
>>point. the cost of diagnostics on the head to see if it really is
>>cracked, labor, etc. just doesn't compare favorably with getting a "new"
>>jdm engine from japan for $290 plus shipping.
>
>
> if this becomes the route i decide to take, where do you recommend
> purchasing a "new jdm engine" (what does jdm mean - i thought the
> engine code was DB-13 or something).

"jdm" is "japanese domestic market". due to tax and emissions laws in
japan, cars usually get junked with only 60k miles on them. that makes
them great for import to the u.s. where these engines still have loads
of useful life.

there's loads of places on the net advertising these kinds of motors,
and i don't endorse any particular one, but something like the site
below is worth investigation:

http://home.pacbell.net/timwang1/38021.html

>
> thanks!
>

Re: 91 civic - tough question about cooling
 

larson.joshua@gmail.com wrote:
>
> first i'd like to say thanks to the great people on this forum for all
> the help they provide.
>
> i've done a search for my problem and i've found some things but
> nothing exactly fits.
>
> i recently performed a head gasket job on my civic. i began this job
> because i had bubbling in my coolant resevoir after driving for a
> while. i also had some electrical issues, but i don't see those as
> related to the bubbles. the bubbling was not boiling. some kind of
> gas was pushing through to the resevoir, and i assumed it was
> compressed gases of some kind coming from the cyclinders through the
> head gasket.
>
> after removing the head, i took it to the shop. they told me the head
> had to be machined by 6 thousands to remove the warp, which seems like
> quite a bit. he also pointed out where the likely breaches of the old
> gasket were.
>
> i cleaned and lapped the surface of the block. there was no apparent
> cracking or warping (i checked for warp with a quality straight edge in
> multiple directions).
>
> put everything back together to spec.
>
> i filled up the cooling system, on an incline with the radiator high.
> bled the system according to haynes.
>
> i've been test driving it for several days, and what happens is a
> little weird. after a light drive, i get a few minutes of bubbles
> (again, not boiling - bubbles) and i can hear coolant sucking past the
> rad cap in pulses. after a heavy drive i get the coolant pulsing, but
> much more bubbling - like the bubbling i used to get.
>
> the only thing i have found that i didn't do was crank on the heater
> when i was filling the cooling system. is it possible that since i did
> not do this, there was a chunk of air in the heater core that is now
> escaping when the car heats up? i ran the car tonight at idle with the
> heater on full blast after discovering this possibility, but the rad
> stayed full (again on an incline) even with the bleeder open.
>
> it seems there are three or four possibilities:
> 1 - block is cracked
> 2 - head is cracked and crack missed by shop
> 3 - heater core had air bubble and now air is working out
> 4 - head gasket was installed improperly
>
> any thoughts? thanks.

-------------------------------------

Keep this in perspective. When the engine gets hot it will force out
some air (if there is air in the system). If there's enough coolant in
the reservoir, (and the rad cap is working correctly), it will suck that
coolant into the engine when it all cools down. The owner's manual is
very clear: Whenever you have work done on the cooling system, you have
to be sure to fill the reservoir to the MAX mark.

Are you keeping the reservoir full enough so the expelled air can get
replaced with coolant? Once the air is all out, the system works
'transparently', but you still have to check it regularly, since some
coolant can escape thru the water pump weep hole. Service manual says
it's acceptable.

'Curly'

Re: 91 civic - tough question about cooling
 

larson.joshua@gmail.com wrote:
>
> first i'd like to say thanks to the great people on this forum for all
> the help they provide.
>
> i've done a search for my problem and i've found some things but
> nothing exactly fits.
>
> i recently performed a head gasket job on my civic. i began this job
> because i had bubbling in my coolant resevoir after driving for a
> while. i also had some electrical issues, but i don't see those as
> related to the bubbles. the bubbling was not boiling. some kind of
> gas was pushing through to the resevoir, and i assumed it was
> compressed gases of some kind coming from the cyclinders through the
> head gasket.
>
> after removing the head, i took it to the shop. they told me the head
> had to be machined by 6 thousands to remove the warp, which seems like
> quite a bit. he also pointed out where the likely breaches of the old
> gasket were.
>
> i cleaned and lapped the surface of the block. there was no apparent
> cracking or warping (i checked for warp with a quality straight edge in
> multiple directions).
>
> put everything back together to spec.
>
> i filled up the cooling system, on an incline with the radiator high.
> bled the system according to haynes.
>
> i've been test driving it for several days, and what happens is a
> little weird. after a light drive, i get a few minutes of bubbles
> (again, not boiling - bubbles) and i can hear coolant sucking past the
> rad cap in pulses. after a heavy drive i get the coolant pulsing, but
> much more bubbling - like the bubbling i used to get.
>
> the only thing i have found that i didn't do was crank on the heater
> when i was filling the cooling system. is it possible that since i did
> not do this, there was a chunk of air in the heater core that is now
> escaping when the car heats up? i ran the car tonight at idle with the
> heater on full blast after discovering this possibility, but the rad
> stayed full (again on an incline) even with the bleeder open.
>
> it seems there are three or four possibilities:
> 1 - block is cracked
> 2 - head is cracked and crack missed by shop
> 3 - heater core had air bubble and now air is working out
> 4 - head gasket was installed improperly
>
> any thoughts? thanks.

-------------------------------------

Keep this in perspective. When the engine gets hot it will force out
some air (if there is air in the system). If there's enough coolant in
the reservoir, (and the rad cap is working correctly), it will suck that
coolant into the engine when it all cools down. The owner's manual is
very clear: Whenever you have work done on the cooling system, you have
to be sure to fill the reservoir to the MAX mark.

Are you keeping the reservoir full enough so the expelled air can get
replaced with coolant? Once the air is all out, the system works
'transparently', but you still have to check it regularly, since some
coolant can escape thru the water pump weep hole. Service manual says
it's acceptable.

'Curly'

Re: 91 civic - tough question about cooling
 

larson.joshua@gmail.com wrote:
>
> first i'd like to say thanks to the great people on this forum for all
> the help they provide.
>
> i've done a search for my problem and i've found some things but
> nothing exactly fits.
>
> i recently performed a head gasket job on my civic. i began this job
> because i had bubbling in my coolant resevoir after driving for a
> while. i also had some electrical issues, but i don't see those as
> related to the bubbles. the bubbling was not boiling. some kind of
> gas was pushing through to the resevoir, and i assumed it was
> compressed gases of some kind coming from the cyclinders through the
> head gasket.
>
> after removing the head, i took it to the shop. they told me the head
> had to be machined by 6 thousands to remove the warp, which seems like
> quite a bit. he also pointed out where the likely breaches of the old
> gasket were.
>
> i cleaned and lapped the surface of the block. there was no apparent
> cracking or warping (i checked for warp with a quality straight edge in
> multiple directions).
>
> put everything back together to spec.
>
> i filled up the cooling system, on an incline with the radiator high.
> bled the system according to haynes.
>
> i've been test driving it for several days, and what happens is a
> little weird. after a light drive, i get a few minutes of bubbles
> (again, not boiling - bubbles) and i can hear coolant sucking past the
> rad cap in pulses. after a heavy drive i get the coolant pulsing, but
> much more bubbling - like the bubbling i used to get.
>
> the only thing i have found that i didn't do was crank on the heater
> when i was filling the cooling system. is it possible that since i did
> not do this, there was a chunk of air in the heater core that is now
> escaping when the car heats up? i ran the car tonight at idle with the
> heater on full blast after discovering this possibility, but the rad
> stayed full (again on an incline) even with the bleeder open.
>
> it seems there are three or four possibilities:
> 1 - block is cracked
> 2 - head is cracked and crack missed by shop
> 3 - heater core had air bubble and now air is working out
> 4 - head gasket was installed improperly
>
> any thoughts? thanks.

-------------------------------------

Keep this in perspective. When the engine gets hot it will force out
some air (if there is air in the system). If there's enough coolant in
the reservoir, (and the rad cap is working correctly), it will suck that
coolant into the engine when it all cools down. The owner's manual is
very clear: Whenever you have work done on the cooling system, you have
to be sure to fill the reservoir to the MAX mark.

Are you keeping the reservoir full enough so the expelled air can get
replaced with coolant? Once the air is all out, the system works
'transparently', but you still have to check it regularly, since some
coolant can escape thru the water pump weep hole. Service manual says
it's acceptable.

'Curly'

Re: 91 civic - tough question about cooling
 

i can't imagine that, despite my crude backer, my 600 grit sanding
removed enough material to make a significant difference in the mating
of the surfaces. i am a metal fabricator and i am sure i removed less
than .0005 or less total. if a gasket can't make that up... the
gasket itself was, say, about 1/16" thick or greater. are they not
designed to take up some slack in the mating surfaces?

the head was done at a shop that pretty much only does that,
particularly for dealerships. it was perfect.

the heater core hasn't been addressed. could my mistake of not turning
up the heat while filling the system leave a large air pocket in the
system?

thanks. this forum is easily the best!


'Curly Q. Links' wrote:
> larson.joshua@gmail.com wrote:
> >
> > first i'd like to say thanks to the great people on this forum for all
> > the help they provide.
> >
> > i've done a search for my problem and i've found some things but
> > nothing exactly fits.
> >
> > i recently performed a head gasket job on my civic. i began this job
> > because i had bubbling in my coolant resevoir after driving for a
> > while. i also had some electrical issues, but i don't see those as
> > related to the bubbles. the bubbling was not boiling. some kind of
> > gas was pushing through to the resevoir, and i assumed it was
> > compressed gases of some kind coming from the cyclinders through the
> > head gasket.
> >
> > after removing the head, i took it to the shop. they told me the head
> > had to be machined by 6 thousands to remove the warp, which seems like
> > quite a bit. he also pointed out where the likely breaches of the old
> > gasket were.
> >
> > i cleaned and lapped the surface of the block. there was no apparent
> > cracking or warping (i checked for warp with a quality straight edge in
> > multiple directions).
> >
> > put everything back together to spec.
> >
> > i filled up the cooling system, on an incline with the radiator high.
> > bled the system according to haynes.
> >
> > i've been test driving it for several days, and what happens is a
> > little weird. after a light drive, i get a few minutes of bubbles
> > (again, not boiling - bubbles) and i can hear coolant sucking past the
> > rad cap in pulses. after a heavy drive i get the coolant pulsing, but
> > much more bubbling - like the bubbling i used to get.
> >
> > the only thing i have found that i didn't do was crank on the heater
> > when i was filling the cooling system. is it possible that since i did
> > not do this, there was a chunk of air in the heater core that is now
> > escaping when the car heats up? i ran the car tonight at idle with the
> > heater on full blast after discovering this possibility, but the rad
> > stayed full (again on an incline) even with the bleeder open.
> >
> > it seems there are three or four possibilities:
> > 1 - block is cracked
> > 2 - head is cracked and crack missed by shop
> > 3 - heater core had air bubble and now air is working out
> > 4 - head gasket was installed improperly
> >
> > any thoughts? thanks.
>
> -------------------------------------
>
> Keep this in perspective. When the engine gets hot it will force out
> some air (if there is air in the system). If there's enough coolant in
> the reservoir, (and the rad cap is working correctly), it will suck that
> coolant into the engine when it all cools down. The owner's manual is
> very clear: Whenever you have work done on the cooling system, you have
> to be sure to fill the reservoir to the MAX mark.
>
> Are you keeping the reservoir full enough so the expelled air can get
> replaced with coolant? Once the air is all out, the system works
> 'transparently', but you still have to check it regularly, since some
> coolant can escape thru the water pump weep hole. Service manual says
> it's acceptable.
>
> 'Curly'

Re: 91 civic - tough question about cooling
 

i can't imagine that, despite my crude backer, my 600 grit sanding
removed enough material to make a significant difference in the mating
of the surfaces. i am a metal fabricator and i am sure i removed less
than .0005 or less total. if a gasket can't make that up... the
gasket itself was, say, about 1/16" thick or greater. are they not
designed to take up some slack in the mating surfaces?

the head was done at a shop that pretty much only does that,
particularly for dealerships. it was perfect.

the heater core hasn't been addressed. could my mistake of not turning
up the heat while filling the system leave a large air pocket in the
system?

thanks. this forum is easily the best!


'Curly Q. Links' wrote:
> larson.joshua@gmail.com wrote:
> >
> > first i'd like to say thanks to the great people on this forum for all
> > the help they provide.
> >
> > i've done a search for my problem and i've found some things but
> > nothing exactly fits.
> >
> > i recently performed a head gasket job on my civic. i began this job
> > because i had bubbling in my coolant resevoir after driving for a
> > while. i also had some electrical issues, but i don't see those as
> > related to the bubbles. the bubbling was not boiling. some kind of
> > gas was pushing through to the resevoir, and i assumed it was
> > compressed gases of some kind coming from the cyclinders through the
> > head gasket.
> >
> > after removing the head, i took it to the shop. they told me the head
> > had to be machined by 6 thousands to remove the warp, which seems like
> > quite a bit. he also pointed out where the likely breaches of the old
> > gasket were.
> >
> > i cleaned and lapped the surface of the block. there was no apparent
> > cracking or warping (i checked for warp with a quality straight edge in
> > multiple directions).
> >
> > put everything back together to spec.
> >
> > i filled up the cooling system, on an incline with the radiator high.
> > bled the system according to haynes.
> >
> > i've been test driving it for several days, and what happens is a
> > little weird. after a light drive, i get a few minutes of bubbles
> > (again, not boiling - bubbles) and i can hear coolant sucking past the
> > rad cap in pulses. after a heavy drive i get the coolant pulsing, but
> > much more bubbling - like the bubbling i used to get.
> >
> > the only thing i have found that i didn't do was crank on the heater
> > when i was filling the cooling system. is it possible that since i did
> > not do this, there was a chunk of air in the heater core that is now
> > escaping when the car heats up? i ran the car tonight at idle with the
> > heater on full blast after discovering this possibility, but the rad
> > stayed full (again on an incline) even with the bleeder open.
> >
> > it seems there are three or four possibilities:
> > 1 - block is cracked
> > 2 - head is cracked and crack missed by shop
> > 3 - heater core had air bubble and now air is working out
> > 4 - head gasket was installed improperly
> >
> > any thoughts? thanks.
>
> -------------------------------------
>
> Keep this in perspective. When the engine gets hot it will force out
> some air (if there is air in the system). If there's enough coolant in
> the reservoir, (and the rad cap is working correctly), it will suck that
> coolant into the engine when it all cools down. The owner's manual is
> very clear: Whenever you have work done on the cooling system, you have
> to be sure to fill the reservoir to the MAX mark.
>
> Are you keeping the reservoir full enough so the expelled air can get
> replaced with coolant? Once the air is all out, the system works
> 'transparently', but you still have to check it regularly, since some
> coolant can escape thru the water pump weep hole. Service manual says
> it's acceptable.
>
> 'Curly'