Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

As mentioned in previous posts, my sister's 99 civic has a damaged valve on
cylinder 3 due to a timing belt breaking. The car is running, albeit poorly
due to no compression on cylinder 3. Once you rev it up, it sounds OK.

Would it be safe to drive the car across town to a different mechanic in this
condition? What are the risks? Or should it be towed?

The drive would be in the city, 50 km/h or less, and revved as low as
possible. Its about a 14km trip.

Please advise.

Thanks
Terry in Winnipeg

--
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Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

and by risks, i mean could we do further damage to the
cylinder/piston/valvetrain by driving with no compression and a damaged valve.


t

T L wrote:
>As mentioned in previous posts, my sister's 99 civic has a damaged valve on
>cylinder 3 due to a timing belt breaking. The car is running, albeit poorly
>due to no compression on cylinder 3. Once you rev it up, it sounds OK.
>
>Would it be safe to drive the car across town to a different mechanic in this
>condition? What are the risks? Or should it be towed?
>
>The drive would be in the city, 50 km/h or less, and revved as low as
>possible. Its about a 14km trip.
>
>Please advise.
>
>Thanks
>Terry in Winnipeg

--
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Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

"T L via CarKB.com" wrote:
>
> and by risks, i mean could we do further damage to the
> cylinder/piston/valvetrain by driving with no compression and a damaged valve.
>
> t
>
> T L wrote:
> >As mentioned in previous posts, my sister's 99 civic has a damaged valve on
> >cylinder 3 due to a timing belt breaking. The car is running, albeit poorly
> >due to no compression on cylinder 3. Once you rev it up, it sounds OK.
> >
> >Would it be safe to drive the car across town to a different mechanic in this
> >condition? What are the risks? Or should it be towed?
> >
> >The drive would be in the city, 50 km/h or less, and revved as low as
> >possible. Its about a 14km trip.
> >
> >Please advise.
> >
> >Thanks
> >Terry in Winnipeg
>
> --
-------------------------

I'd remove the spark plug wire from the plug and put an old 'dummy' plug
on the wire, with the metal part of the plug grounded, so it sparks
normally. Otherwise, I doubt anything bad could happen. (the high
tension needs to find it's way to ground or it will 'blaze a new trail"
inside the cap, or igniter)

'Curly'

Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

Curly, not sure what you mean. How could I ground the 'dummy' plug? (IE
make it stay grounded while driving the car.)

Also, if the gas in the cylinder is not being burned off, wouldn't it cause
the oil on the cylinder wall to be washed away, causing potential damage to
the rings, and contamination of the engine oil? This is one of the big
concerns I have.



'Curly Q. Links' wrote:
>> and by risks, i mean could we do further damage to the
>> cylinder/piston/valvetrain by driving with no compression and a damaged valve.
>[quoted text clipped - 17 lines]
>>
>> --
>-------------------------
>
>I'd remove the spark plug wire from the plug and put an old 'dummy' plug
>on the wire, with the metal part of the plug grounded, so it sparks
>normally. Otherwise, I doubt anything bad could happen. (the high
>tension needs to find it's way to ground or it will 'blaze a new trail"
>inside the cap, or igniter)
>
>'Curly'

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Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

"T L via CarKB.com" <u10197@uwe> wrote in message news:5819fde17d50c@uwe...
> Curly, not sure what you mean. How could I ground the 'dummy' plug? (IE
> make it stay grounded while driving the car.)
>
> Also, if the gas in the cylinder is not being burned off, wouldn't it
> cause
> the oil on the cylinder wall to be washed away, causing potential damage
> to
> the rings, and contamination of the engine oil? This is one of the big
> concerns I have.
>
This brings me to what I would add - disconnect the injector. Injecting fuel
into that cylinder will come to no good.

Mike

>
>
> 'Curly Q. Links' wrote:
>>> and by risks, i mean could we do further damage to the
>>> cylinder/piston/valvetrain by driving with no compression and a damaged
>>> valve.
>>[quoted text clipped - 17 lines]
>>>
>>> --
>>-------------------------
>>
>>I'd remove the spark plug wire from the plug and put an old 'dummy' plug
>>on the wire, with the metal part of the plug grounded, so it sparks
>>normally. Otherwise, I doubt anything bad could happen. (the high
>>tension needs to find it's way to ground or it will 'blaze a new trail"
>>inside the cap, or igniter)
>>
>>'Curly'
>
> --
> Message posted via CarKB.com
> http://www.carkb.com/Uwe/Forums.aspx...-cars/200511/1

Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

"Michael Pardee" <michaeltnull@cybertrails.com> wrote in
news:TIKdnfqwkrklRRHeRVn-vA@sedona.net:

> "T L via CarKB.com" <u10197@uwe> wrote in message
> news:5819fde17d50c@uwe...
>> Curly, not sure what you mean. How could I ground the 'dummy' plug?
>> (IE make it stay grounded while driving the car.)
>>
>> Also, if the gas in the cylinder is not being burned off, wouldn't it
>> cause
>> the oil on the cylinder wall to be washed away, causing potential
>> damage to
>> the rings, and contamination of the engine oil? This is one of the
>> big concerns I have.
>>
> This brings me to what I would add - disconnect the injector.
> Injecting fuel into that cylinder will come to no good.
>
> Mike

yes,the unburned fuel will throw off the O2 sensor,and the ECU will
misadjust the other cylinders.

Better to just leave the spark plug the way it is,not provide a "dummy"
plug.

--
Jim Yanik
jyanik
at
kua.net

Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

Thanks for everyones input! I will unplug the injector and leave everything
else as is. For a short trip, I doubt it will create any big problems.

t

Jim Yanik wrote:
>>> Curly, not sure what you mean. How could I ground the 'dummy' plug?
>>> (IE make it stay grounded while driving the car.)
>[quoted text clipped - 10 lines]
>>
>> Mike
>
>yes,the unburned fuel will throw off the O2 sensor,and the ECU will
>misadjust the other cylinders.
>
>Better to just leave the spark plug the way it is,not provide a "dummy"
>plug.
>

--
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Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

> yes,the unburned fuel will throw off the O2 sensor,and the ECU will
> misadjust the other cylinders.
>
> Better to just leave the spark plug the way it is,not provide a "dummy"
> plug.

I'm imagining the combustion chamber pooling up with unburned gas, or would
it just shoot out the exhaust valves anyway?

Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

Is it really worth it to try? What will you save? $50 or less?

I wouldn't do it.

G-Man


"T L via CarKB.com" <u10197@uwe> wrote in message news:58193bba00d93@uwe...
> As mentioned in previous posts, my sister's 99 civic has a damaged valve
> on
> cylinder 3 due to a timing belt breaking. The car is running, albeit
> poorly
> due to no compression on cylinder 3. Once you rev it up, it sounds OK.
>
> Would it be safe to drive the car across town to a different mechanic in
> this
> condition? What are the risks? Or should it be towed?
>
> The drive would be in the city, 50 km/h or less, and revved as low as
> possible. Its about a 14km trip.
>
> Please advise.
>
> Thanks
> Terry in Winnipeg
>
> --
> Message posted via CarKB.com
> http://www.carkb.com/Uwe/Forums.aspx...-cars/200511/1

Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

"T L via CarKB.com" wrote:
>
> and by risks, i mean could we do further damage to the
> cylinder/piston/valvetrain by driving with no compression and a damaged valve.
>
> t

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

The other guys are more correct . . Unplug the injector. No worries
about any backfiring, but you might still generate a 'misfire' code, but
so what? At least it can't backfire if there's no fuel/air mixture
present.

I was referring to chassis ground, like any part that's steel. Doesn't
matter anyway, but it's worth remembering. Honda spark has to go
_somewhere_ or it will go to the wrong places.

'Curly'

Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

T L via CarKB.com wrote:
> As mentioned in previous posts, my sister's 99 civic has a damaged valve on
> cylinder 3 due to a timing belt breaking. The car is running, albeit poorly
> due to no compression on cylinder 3. Once you rev it up, it sounds OK.
>
> Would it be safe to drive the car across town to a different mechanic in this
> condition? What are the risks? Or should it be towed?
>
> The drive would be in the city, 50 km/h or less, and revved as low as
> possible. Its about a 14km trip.
>
> Please advise.
>
> Thanks
> Terry in Winnipeg
>
14k's are no problem. it's just one or two valves a little open -
nothing different to a burnt valve. and don't worry about driving
normal speed - if anything it'll be better as you'll get less blowback
if it's on the intake side.

Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

"T L via CarKB.com" wrote:
>
> Curly, not sure what you mean. How could I ground the 'dummy' plug? (IE
> make it stay grounded while driving the car.)
>

With one of these, http://tinyurl.com/cb9ky part number 2756 for HEI
systems.

Eric

Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

"MAT" <marcoat*RM_@SPAM_*hotmail.com> wrote in
news:8Padnaza0JhIchHeRVn-rA@comcast.com:

>
>> yes,the unburned fuel will throw off the O2 sensor,and the ECU will
>> misadjust the other cylinders.
>>
>> Better to just leave the spark plug the way it is,not provide a
>> "dummy" plug.
>
> I'm imagining the combustion chamber pooling up with unburned gas, or
> would it just shoot out the exhaust valves anyway?
>
>
>

Of course it would get pushed out the exhaust.The cylinder still remains an
air pump.A little leakage around a bent valve is not going to stop that.

The injectors atomize the liquid,so it will be a burnable fuel-air
mix,vapor,not a liquid.

--
Jim Yanik
jyanik
at
kua.net

Re: Good Idea Bad Idea? drive a civic with no compression on a cylinder
 

"'Curly Q. Links'" <motsco__@interbaun.com> wrote in
news:438CFCFD.3E8B81B3@interbaun.com:

> "T L via CarKB.com" wrote:
>>
>> and by risks, i mean could we do further damage to the
>> cylinder/piston/valvetrain by driving with no compression and a
>> damaged valve.
>>
>> t
>
> --------------------------
>
> The other guys are more correct . . Unplug the injector. No worries
> about any backfiring, but you might still generate a 'misfire' code,
> but so what? At least it can't backfire if there's no fuel/air mixture
> present.
>
> I was referring to chassis ground, like any part that's steel. Doesn't
> matter anyway, but it's worth remembering. Honda spark has to go
> _somewhere_ or it will go to the wrong places.
>
> 'Curly'
>

Let it spark in the cylinder,it won't harm anything.
No fuel-air mix to burn with an injector disabled,but that does not matter.
Those engines(non-Honda) that share a coil between two cylinders do the
same thing;allowing a spark in a cylinder with no fuel-air mix.

--
Jim Yanik
jyanik
at
kua.net