Our Community is 940,000 Strong. Join Us.


Oil on #7 spark plug


laxman21
06-07-2009, 12:03 PM
Getting some oil on the 7 spark plug and out on the boot.

Any ideas where it might be coming from?

j cAT
06-07-2009, 07:54 PM
Getting some oil on the 7 spark plug and out on the boot.

Any ideas where it might be coming from?

valve cover////spill oil when filling...///leak at fill pipe gasket////replace PVC/check hoses on pcv/crankcase vent..

laxman21
06-08-2009, 08:42 AM
valve cover////spill oil when filling...///leak at fill pipe gasket////replace PVC/check hoses on pcv/crankcase vent..


Replaced the pcv valve. This cylinder has been burning oil for a few years and eventually fouls the plug, just hope it's not being forced out around the plug.

iroc343
06-08-2009, 10:29 AM
Sounds like two separate issues. In the cylinder it's probably a worn guide causing the valve seal to leak. My experience has been don't waste your time replacing the valve seals. The only way to fix this right is to pull the head and bronze wall the guides. I have a hard time believing that oil could get past the threads and the taper seat to make it to the boot unless the taper seat was damaged.

j cAT
06-08-2009, 11:13 AM
Sounds like two separate issues. In the cylinder it's probably a worn guide causing the valve seal to leak. My experience has been don't waste your time replacing the valve seals. The only way to fix this right is to pull the head and bronze wall the guides. I have a hard time believing that oil could get past the threads and the taper seat to make it to the boot unless the taper seat was damaged.

Finally I find another person who believes as I do,,,,valve seals arn't usually the problem....the head must be removed then the guides reworked...with a good machine shop doing this you will have a better running vehicle...

I don't think/ever seen one valve guide have wear,,,usually they are all bad...

could be a cracked ring...if the vehicle had a gasket issue and coolant got into that cylinder the rings may have gotten stuck,then cracked...

laxman21
06-08-2009, 05:28 PM
Finally I find another person who believes as I do,,,,valve seals arn't usually the problem....the head must be removed then the guides reworked...with a good machine shop doing this you will have a better running vehicle...

I don't think/ever seen one valve guide have wear,,,usually they are all bad...

could be a cracked ring...if the vehicle had a gasket issue and coolant got into that cylinder the rings may have gotten stuck,then cracked...



I guess I will have to get a cylinder leak down test.

j cAT
06-08-2009, 10:14 PM
I guess I will have to get a cylinder leak down test.

when you find the exact cause let us know ,,,good luck.

laxman21
06-08-2009, 10:18 PM
when you find the exact cause let us know ,,,good luck.



Used some seafoam today to clean some carbon off. Well see if that helps any.

j cAT
06-08-2009, 10:32 PM
Used some seafoam today to clean some carbon off. Well see if that helps any.

I was gonna recommend adding marvel mystrey oil to the fuel....1oz/10 gallons...overtime the compression rings will begin to move easier and you may find it will not foul the plug as quickly...

I have used this product for many years....it is very good for non damaging cleaning and lubrication...

this product with constant use in the fuel for small engines will keep them running forever...I still have a 1979 chain saw...also a 19year old lawn mower..


some of these fuel cleaners must be used with caution,,,follow the directions more is not better than recommended...

Add your comment to this topic!