Gas leaking out of front left cylinder
- Jim Clement
- 356 Fan
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- Tag: 1957 356 A Coupe
- Location: Calgary Alberta
Gas leaking out of front left cylinder
okay.. the boys have started up my engine.. and .. three out of four cylinders are firing well.
here is what I know
1) engine is newly rebuilt
2) good compression on all cylinders
3) there is spark at to all cylinders.
4) Carbs were recently rebuilt, but had to be rejetted to run at 3500 feet above sea level
5) fuel pump is also rebuilt and tested, is running at correct psi
6) front left cylinder plug is wet after running.. so we know there is to much fuel.
7) when running the engine on the test stand, when you goose the gas, it comes with a small cloud of white ish smoke..
8) the big idle adjustment screws have been adjusted to optimal.
what do I look for to correct this ??
here is what I know
1) engine is newly rebuilt
2) good compression on all cylinders
3) there is spark at to all cylinders.
4) Carbs were recently rebuilt, but had to be rejetted to run at 3500 feet above sea level
5) fuel pump is also rebuilt and tested, is running at correct psi
6) front left cylinder plug is wet after running.. so we know there is to much fuel.
7) when running the engine on the test stand, when you goose the gas, it comes with a small cloud of white ish smoke..
8) the big idle adjustment screws have been adjusted to optimal.
what do I look for to correct this ??
- Jim Clement
- 356 Fan
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- Joined: Tue Oct 26, 2010 10:46 am
- Tag: 1957 356 A Coupe
- Location: Calgary Alberta
Re: Gas leaking out of front left cylinder
8) all valves all appear to be adjusted and working correctly.. compression test shows 150 plus across all 4 cylinders
- Ron LaDow
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- Jim Clement
- 356 Fan
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- Tag: 1957 356 A Coupe
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- Craig Richter
- 356 Fan
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- Location: San Miguel de Allende/Traunkirchen
Re: Gas leaking out of front left cylinder
Rings don't seal immediately on these motors. Duane Spencer gave me a set of his first pistons (now Shasta) to test, and the chrome rings he supplied took about 1000 miles to completely seal. 30,000 miles later they are still perfect. Run it for awhile and report back...
- Ron LaDow
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Re: Gas leaking out of front left cylinder
I'm with Craig; it's probably oil.
Give it some time, but do a tune at about 500 miles or so. You'll find all the parts that are getting friendly with each other.
Give it some time, but do a tune at about 500 miles or so. You'll find all the parts that are getting friendly with each other.
Ron LaDow
www.precisionmatters.biz
www.precisionmatters.biz
- Doug McDonnell
- 356 Fan
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- Location: Augusta,Michigan
Re: Gas leaking out of front left cylinder
For S&Gs clean your jets for cylinder #3
1965 356C 2000 BMW 740i Sport 1967 Honda CL77 There is never enough time to do it right, but always enough time to do it over.
- Jim Clement
- 356 Fan
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- Tag: 1957 356 A Coupe
- Location: Calgary Alberta
Re: Gas leaking out of front left cylinder
the wetness on the plug when pulled out is gas not oil
when we pull the spark plug wire off of the bad cylinder.. it has no effect.. so we know that cylinder is not operating..
we know it is the carburetor . just do not know why or how to fix it..
when we pull the spark plug wire off of the bad cylinder.. it has no effect.. so we know that cylinder is not operating..
we know it is the carburetor . just do not know why or how to fix it..
-
- 356 Fan
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Re: Gas leaking out of front left cylinder
Carbs 32NDIX? Or? Check for loose jet. Engine out pull the exhaust off #3 and check for raw fuel.
I'm going with a main jet being loose. Also check that the plug is working as it should. Too much fuel or too little spark. Are these little buggers fun or what?
Good luck, it will all work out,
Rusty
I'm going with a main jet being loose. Also check that the plug is working as it should. Too much fuel or too little spark. Are these little buggers fun or what?
Good luck, it will all work out,
Rusty
Rusty
- David Jones
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Re: Gas leaking out of front left cylinder
Jim, switch carbs side to side. Don't worry about linkage as all you are doing is checking for combustion. If problem follows carb it is carb, if not it is ignition.
If I had known I would live this long I would have pushed the envelope a little harder.
Cymru am byth
David Jones #9715
Cymru am byth
David Jones #9715
- Jim Clement
- 356 Fan
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- Tag: 1957 356 A Coupe
- Location: Calgary Alberta
Re: Gas leaking out of front left cylinder
there is lots of raw fuel.. it is actually leaking out of the lower exhaust junction between the J tube and the muffler connection.
- Doug McDonnell
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Re: Gas leaking out of front left cylinder
Take the top of the carb off and check for stuck float needle valve and sunk float. Measure the fuel level and check for loose jet as mentioned. https://porsche356registry.org/article/30
1965 356C 2000 BMW 740i Sport 1967 Honda CL77 There is never enough time to do it right, but always enough time to do it over.
- Jim Clement
- 356 Fan
- Posts: 1471
- Joined: Tue Oct 26, 2010 10:46 am
- Tag: 1957 356 A Coupe
- Location: Calgary Alberta
Re: Gas leaking out of front left cylinder
thanks for the link...
I will print this off and have it beside me when I take the top off !!!
after thinking about it with all the above advice..I am going with a loose main jet..
as one of the last things done to the car was that I had the jets changed.. so I am guessing.. it is loose...
I will print this off and have it beside me when I take the top off !!!
after thinking about it with all the above advice..I am going with a loose main jet..
as one of the last things done to the car was that I had the jets changed.. so I am guessing.. it is loose...