Need oil burning help

[a_thomasmr23]

SO on the way home from drill today my car starts running like ass and is making a mess of blue smoke when i get up to about 3k rpm at 50% throttle or more. I guess oil. Right. Number 5 plug is solid, 1 is real bad too all have some oil on them. I check the tube that goes from the valve cover to the intake (PCV hose) and its about 3/4 closed with crap. Is this the most likely problem or am i screwed?

edit

also head was put on by me after t-belt break. all new valve stem guide seals. No trouble with engine since head replace ~ 2500 mi.

[jlevie]

You need compression an leak down numbers to begin to assess where the problem might be.

[a_thomasmr23]

dont have a leak down tester but here are the compression numbers test was done as per Bentley minus i forgot to hold the throttle open, 4 revs per test engine warm and there was already oil in the cly. so this is basicly a wet test already

1- 140
2- 143
3- 137
4- 137
5- 157
6- 147

[Knockenwelle]

What kind of oil have you been using, and how cold has it been?

[a_thomasmr23]

50ish i'm using 10-40 royal purple

[jlevie]

There's definitely a problem as shown by the compression results. You need leak down numbers to complete the diagnosis.

[a_thomasmr23]

what are you thinking from the compression i though that they looked pretty ball park

[Rolla1990]

You need leak down numbers to complete the diagnosis.

Plain and simple, you NEED to do a leakdown test to further diagnose. It will tell you how the oil is getting into the cylinders.

[Knockenwelle]

What we're trying to say is:

Those numbers look suspiciously unremarkable, though a little low. I'd expect around 170-180, maybe a little more, on a well-sealed, stock-cammed M20. The spread isn't too bad, indicating only one cylinder is likely not a problem. Ring wear could explain this kind of oil consumption and compression drop, but not in a hurry like you said. The chunkies plugging up the works have me wondering about oil contamination. Have you been driving only short trips lately? As said already, leak it down to find out where the blood is going.

[a_thomasmr23]

all most all of my trip are short 15 mins runs to and from work with 2hr drives on the weekend I'll see about getting a tester today thanks for all the help though guys

[a_thomasmr23]

so after a 1000 yrs i found a leak down tester

all the cylinders were about the same in the 13-18% range and all the air was in the crankcase

it also burns oil all the time now instead of just under load I'm thinking rings for sure

[Hallen]

Is it worse on start up or when coming off the throttle quickly? Or is it pretty constant?

[jlevie]

Leak down numbers on an engine is great condition would be 5-10%. Up to 20% would represent an engine that is still in pretty good condition. Over 30% would be a problem. So it sounds like the rings are in pretty good shape. That in turn suggests a problem with the crankcase vent system or bad valve seals.

A leak into the crankcase (bad dipstick o-rings, leaking oil filler cap, etc) will cause excess air movement through the crankcase and thus excessive oil consumption. Worn valve seals/guides will definity casue increased oil consumption.

[a_thomasmr23]

valve seals are know good just replaced them when i build the head about 2 months ago. what am i looking for on the crankcase to test? I talking about burning a 1 qt in a 50mi trip over the weekend.

deff worst off throttle then when idling

[SpecM]

valve seals are know good just replaced them when i build the head about 2 months ago

where did you buy them? just because they are new does not always mean they are good...

replace the crankcase vent (and plugs!) at least, and see what happens

and/or try some Lucas oil additive, good stuff there