Doing my compression test this winter,pulled all the plugs and number 5 is fouled really bad. Ido a compression test and compression is actually 20 pds higher than the last time I tested. None of the other cylinders changed. Could this be a stuck valve?
Prefectca said
Nov 18, 2022
The higher compression is probably carbon build up from oil burning. Whats the history on the engine?
Paul
zak404 said
Nov 18, 2022
It was back firing awhile ago due to a vacuum leak and it was doing it on that engine side, it has about 50000 miles on engine.
oshawacliff said
Nov 18, 2022
Seafoam candidate?
Prefectca said
Nov 18, 2022
How is your pcv routed? Could the pcv system be allowing oil to be drawn into the intake manifold and burned by #5 cylinder? I cant say for sure why #5 is burning oil, but I have seen oil from the lifter valley sucked l past the intake gasket. Usually caused by having the cylinder heads planed affecting the alignment of the intake and heads. Could be a valve guide or valve seal problem or a broken or sticking piston ring. If the engine works good other than the plug fouling it wouldnt hurt to try something like sea foam as Cliff suggested to try and clean the carbon out and maybe free up a sticking piston ring.
-- Edited by Prefectca on Friday 18th of November 2022 09:36:42 PM
zak404 said
Nov 18, 2022
Ok thanks that may help as I recently moved the PVC valve to that side of the engine. I will switch it back to the other side and see if it makes a difference. I take seafoam is something you pour through the carb to clean it out? The heads are only about 3 years old with maybe 3000 miles on them, Edelbrock street performer heads.
Prefectca said
Nov 18, 2022
I personally havent used sea foam but it has good reviews. Perhaps if you do a search on this forum you may find some information. Sea foam is available at Canadian Tire.
Ok thanks that may help as I recently moved the PVC valve to that side of the engine. I will switch it back to the other side and see if it makes a difference. I take seafoam is something you pour through the carb to clean it out? The heads are only about 3 years old with maybe 3000 miles on them, Edelbrock street performer heads.
Do you know if there is a baffle inside the valve cover where you moved the PCV valve to?
oshawacliff said
Nov 19, 2022
oshawacliff wrote:
Seafoam candidate?
Sea Foam comes in a variety of products for gas and oil. I usually ad the oil product and drive 1000 km before the next oil change. Just dump a can in the gas tank filler, cant hurt anything. Seems to work.
Diesel products available also.
-- Edited by oshawacliff on Saturday 19th of November 2022 12:02:56 PM
seventy2plus2 said
Nov 19, 2022
The PCV valve is to be in the drivers (left) valve cover. The reason for that is the rotation of the crankshaft causes a buildup of crankcase gasses on that side, and they need to be evacuated. A vent is then provided on the passenger (right) valve cover to replace the evacuated air.
zak404 said
Nov 19, 2022
Yes both sides have baffles in them, I have always have the PVC on the passenger side in the past
zak404 said
Nov 19, 2022
oshawacliff wrote:
oshawacliff wrote:
Seafoam candidate?
Sea Foam comes in a variety of products for gas and oil. I usually ad the oil product and drive 1000 km before the next oil change. Just dump a can in the gas tank filler, cant hurt anything. Seems to work.
Diesel products available also.
-- Edited by oshawacliff on Saturday 19th of November 2022 12:02:56 PM
Doing my compression test this winter,pulled all the plugs and number 5 is fouled really bad. Ido a compression test and compression is actually 20 pds higher than the last time I tested. None of the other cylinders changed. Could this be a stuck valve?
Paul
Seafoam candidate?
How is your pcv routed? Could the pcv system be allowing oil to be drawn into the intake manifold and burned by #5 cylinder? I cant say for sure why #5 is burning oil, but I have seen oil from the lifter valley sucked l past the intake gasket. Usually caused by having the cylinder heads planed affecting the alignment of the intake and heads. Could be a valve guide or valve seal problem or a broken or sticking piston ring. If the engine works good other than the plug fouling it wouldnt hurt to try something like sea foam as Cliff suggested to try and clean the carbon out and maybe free up a sticking piston ring.
-- Edited by Prefectca on Friday 18th of November 2022 09:36:42 PM
I personally havent used sea foam but it has good reviews. Perhaps if you do a search on this forum you may find some information. Sea foam is available at Canadian Tire.
https://www.canadiantire.ca/en/pdp/sea-foam-motor-treatment-473-ml-0387800p.html?gbraid=0AAAAADojZpiSVD3uogh72zC-HzBdnJZxT&gclid=EAIaIQobChMInpzD46m5-wIVG_LjBx3kQQGDEAQYASABEgI7jfD_BwE&gclsrc=aw.ds#store=417
Do you know if there is a baffle inside the valve cover where you moved the PCV valve to?
-- Edited by oshawacliff on Saturday 19th of November 2022 12:02:56 PM
Yes both sides have baffles in them, I have always have the PVC on the passenger side in the past
Ok will try that in the spring