oil in my cylinder, leaky valve guide?

kmarccoco · #1 (**permalink**) 06-05-2005, 07:36 PM

hi all, i just bought my cobra two weeks ago. it has 351 stroker with aluminum heads(only 5000 miles). well, i was getting a bit of smoke(smelled mostly like gas) out of my passenger side pipe. i pulled the plugs and found the second cylinder from the front(pass side) had an wet oil/gas plug. i took coil wire off and turned it over with plug out. a bit of oil shot out. all other plugs/cylinders were fine.

does this seem like a leaky valve guide, or worse? it has roller rockers and cam. thanks ken

Tommy · #2 (**permalink**) 06-06-2005, 05:23 AM

In my limited experience, valve guides leak due to wear accumulated over many miles. As new as your engine is, the leak is likely caused by something else (e.g., broken ring, cracked piston, etc.). In any case, you'll need to have someone pull the head on that side and inspect everything to be sure.

Zoom This · #3 (**permalink**) 06-06-2005, 03:32 PM

You may very well have a leaky valve seal and/or valve guide. How much oil are you using?

Tinker51 · #4 (**permalink**) 06-06-2005, 09:19 PM

Color of the smoke? Black is fuel. White/blue is oil.
Does it smoke all the time or does only blow a puff at startup?
Could be that things just never seated right.

kmarccoco · #5 (**permalink**) 06-07-2005, 02:12 AM

its kind of hard to tell color of smoke, i just noticed it this weekend. i thought it looked grey/black and smelled like fuel as if running real rich. it smokes even after driving for a while. also smokes a little near sparkplug/header area. i'm baffled. but, when i removed the plug, and cranked it over(with coil wire off) it spit out a bit of fresh oil. plug was also fouled. its down about 1 quart. last time i checked oil level was two weeks ago(bout 250 miles) and it was full. there is also alot of black varnish build up in the carberator throat.

cleggy · #6 (**permalink**) 06-08-2005, 04:24 PM

Pull the head, its the only way to find the problem for sure. If you're spitting oil, somthing is assuredly broken, don't run it any more, or somthing else will go also. From the carbon in the carb, it might be a cracked valve guide.

kmarccoco · #7 (**permalink**) 06-09-2005, 01:47 AM

well jury is in... i'm lucky. turns out that it was a bad intake manifold gasket. mechanic said that good amount of oil was getting in from this problem. oil seepen into cylinder #2 and intake system.. i pick it up tomorrow/ hope that was it. he did a leak down test that showed no problems in lower end.