383 stroker, hypereutectic pistons, cast rings gapped at 0.026" top, 0.016" for second and oil rings. 10.0:1 compression. New heads.

Engine has 3,000 miles and consumes a quart of oil every 1500 miles. Also, oil gets gasoline contamination - turns really black. Externally no outward signs of oil leaking.

Did a compression check - 205 - 215 psi in the cylinders.


Is the oil consumption normal?

I can try leaning the engine out to reduce the oil contamination. Any other thoughts?

 

intake gasket leaking fuel into lifter valley??

oil consumption-valve seals leaking??

 

Would deffinately get it checked n find out what is before driven it again. Had the same problem with gas in the oil n spun the # 5 n 8 rod bearings. Either the rings didnt seat good r was washed out. Still have no clue what caused it. The choke wasnt hung r anything on the carb, It did run real rich though. Wouldnt drive until fixed thats me though. Learn from experience.

 

I would get a new set of intake gaskets and install them just to be safe, there cheap and fairly easy to install. Just use a little bit of high temp silicone to stick the gaskets to the manifold first then once it has dryed enough to hold them on to it but not 100% dry re install the intake and let it finish drying before running.

 

Leakdown testtime.

 

Mechanical or electric fuel pump?

 

Electric Fuel pump - the engine actually has electronic fuel injection. All the injectors are good, no leaking.

I actually thought it might be the intake gaskets and checked the bolts to see if they were tight. They were slightly loose, so I torqued 'em up.

As for the oil consumption - I had a couple people suggest it was sucking up oil thru the PCV valve and burning it. Thoughts on this??? Also, is there any way, short of taking the heads off, to determine if the guides and seals are no good?? The odd thing is that the engine does not belch blue smoke at start-up or when you blip the throttle.

In the meantime, I am going to do a leak-down test as soon as the tool arrives at my door. Hopefully another day or two. I will post results on this as soon as I complete it.

Thanks to everyone for their continued thoughts on this matter.

 

If you are using an electric pump, sounds like the regulator isn't working and the injector's are overwhelmed with fuel. Make sure you have the pressure regulated. As said by others, the fuel is washing the cylinders down and you haven't got the rings properly seated. Take care of the fuel problem, put fresh oil and filter in and try again.

 

Okay, did a leakdown terst last night.

All cylinders are 5-7% leakdown of baseline. Well within acceptable limits.


Maybe I will have a peak at that regulator....


Any other thoughts???

 

Normal Oil comsumption 1 qt per 1000 could be less but should not affect plugs. May hurt detonation, make worse.

Race engines can be built looser (more clearance) than stock. More heat makes for tight parts (seized pistons or slap, broke rings or oil use). It depends on the builder.

Check your afr, rich running motor = low viscocity oil = bad bearings. This is more true at Idle. Big cams tend to make engine run rich. Big ports and low air speed do not help.

Want a lopey Idle? Run it rich. Back in the day, we use to pull out hand choke to act like "Big Cam". All it does is wash cylinders and thin oil. 50w anybody.

Just my silly thoughts on this.

 

As I originally posted, I consume a quart every 1500 miles. It just seems high to me. Especially when alot of engines out of the factory don't burn anything in 5,000 miles.

I think the idle is a bit rich, so I will work on leaning it out a bit.

BTW, I run 30 wt right now.