M20b25 engine problem.

Post Sun Mar 18, 2012 3:32 pm

Hi zoners, any one got a clue what my problem could be?? Done a re build on my engine and since have had a problem, it was an engine that had sat for a while I purchased of a friend, once I put it in it run perfectly then after 700 miles it developed a misfire, I took the plugs out to give them a clean and plug 6 closest to the bulk head was clogged up with what looks like cooked on oil??!! Cleaned it off then again after about 700 miles it did the same again??!! There is no blue smoke at idle or under load?? Any one have any idea or any advice??

Post Sun Mar 18, 2012 6:37 pm

do a compression test dude

pull all the plugs out, do each cylinder in turn, then repeat but add a small amount of oil to each bore via the plug holes 1st

report back and we'll get ya sorted.

if the oil seems to be on the thread as well I'd suggest a new rocker cover gasket , and the half moon camshaft plugs too. the oil will be drawn into the pug with the engine running just from heat and capillary action......