Help, newly built engine burns a lot of oil

[Neffets]

So my newly built 2.7 with JE 9.5 and Dc 30 is going through oil like gasoline...

At first i didn't notice since I was changing oil often, but now I have driven 500miles, and was ready for the first valve adjustment, but the last 100miles I've smelled the burnt oil and seen the level on my gauge going lower and lower.
So I have lived in denial for some 100miles (hoping it was because it's running rich)
I did the break in with my old carbs, but it's running a bit on the rich side, 12:1 @crusing, 11.5 on moderate to heavy acceleration.

Today I parked here in the garage after doing a 100miles drive, filled oil up so it was 3/4 on the gauge, when i came home it was on the red mark...
Engine is dry no leakage, but I can see blue smoke coming out at high rpm.
It's not pulling oil into the carbs, since I have a catch can and a breather outside of the air filter. New valve guides and seals.
Oil is 20w-50, break in as per wayne's book

JE pistons and rings gap:
1st ring 0.15mm
2 ring 0.25mm
Oil ring 0.35mm

Piston to cyl clearance 0,0015"

Did a compression check today warm engine.
Cyl1 207psi
Cyl2 210psi
Cyl3 214psi
Cyl4 194psi
Cyl5 204psi
Cyl6 210psi

9.35% (but valves not adjusted yet if that affects it)

And this is what the spark plugs looked like.




Doing a leak down test tomorrow, but when driving the car it appears that it burns oil at above 3500-4000rpm, or at least that's when its visible.

So I guess my oil rings haven't seated? Will they do or is it time to pull the engine out again?

[3literpwr]

Are the rings in the proper orientation to each other? 3, 6 and 9 o'clock? Also, your oil ring gap seems large. I recall, my JE pistons stating .0015 gap for oil ring...

[Neffets]

JE oil ring gap says 0,015", I'm at 0,0138"
1&2 ring is at 8-4 o'clock, oil expander ring 12, top&bottom rails at 10-14
And oil expander ring is not overlapping

[Steve@Rennsport]

Seat the rings first, THEN do a leakdown as thats what will confirm they have seated.

Oil consumption is due to lack of ring sealing, cylinder wall finish, type of ring package and ring gaps. Sometimes piston fitment (thats a whole 'nuther story) plays a role here, too.

[Dan J]

You sure those JE's are in Nicasil cyl's?
Seems like a dumb question but I've seen them in alusils

[JFairman]

Here's the factory manual instructions for ring gap positions. I installed new Mahle 3.3 911 turbo pistons and cylinders from a sealed box with the ring gaps positioned like this and everything is perfect and it runs great. It doesn't burn any oil.


Good luck with yours.

[James Brown]

a good hard run for a hour or so at high rpm might help seat those rings, don't be gentle.

[snbush67]

Don't trust the gauge use the stick. The difference between the red marks and 3/4 on the gauge for my car equals about 1/2 quart. So that's not really alarming for an engine that isn't broke in.

I used a thinner oil for break in and drove the dog snot out of it, now I hardly burn any oil but during break in had similar results as you.

[snbush67]

Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power

[Neffets]

JE's are in nikasils yes, I also measured RA surface can't remember the result but it was within mahle spec.




I think i've read all of the internet about engine break in, but i'm at 500miles now and burning 0,5-1 quart of oil on 100miles!
Is the 20w-50 maybe to thick , it's almost freezing temperature here, if that has any affect.

So I guess the rings should have been seated at 500miles? or continue driving and hope for the best? (i'm not babying anymore)

[Raceboy]

Rings will not seat with babying, they need maximum cylinder pressure to push them to cylinder walls, pure material pressure is not enough.
You do not need high rpm but rather high load. Make few 3rd or 4th gear runs from 2000 rpm to say 5000 rpm, that will give rings good pressure and you will not need to rev the engine...

[jhg41977]

Revboy has it. I did the same for the first 1,000 miles very early in the morning. Third gear 2,000rpm then wide open throttle to 5,000rpm shift to fourth wide open throttle up to 5,000rpm. Back off the throttle completely, coast down to 2,000rpm, downshift to second, coast down to 2,000rpm. Repeat over and over again. Change oil at 500miles, again at 1,000miles. Then do a leak down. Mine came in at 1-1.5% in each cylinder. The engine runs very strong, burns almost no oil.

[jcunning]

The compression looks pretty good.
I would do a leakdown test and see what happens. If you get a lot of leakage into the crankcase, then I would suspect the rings never seated.

The next possibility is that the valve guides are leaking oil into the cylinder. To have all six plugs look exactly the same means all cylinders have the same issue and I think 6-12 bad valve guides is unlikely, but not impossible.

Most of the "breaking in" is done in the first 100 miles, so I would start some diagnosis to try and find the problem.

My personal guess is that the rings never seated right. Oil is not being scrapped from the cylinder walls and is being burned up.

You posted: "JE oil ring gap says 0,015", I'm at 0,0138"
This seems like you are below the minimum and could be the issue. The top ring could be binding in the bore.

Further down you say the gap is .15mm. I really hope this is a mis-type as this is way below the minimum gap needed. 0.016" = 0.4mm

I recently went through a similar disaster with a 4 cylinder turbo engine. I was burning 1 qt every 500 miles. I made a few mistakes that caused my rings to not seat. I redid the engine again and fixed all my mistakes from before and now it doesn't burn any oil after 1000 miles.

[Steve@Rennsport]

Originally Posted by Raceboy

Rings will not seat with babying, they need maximum cylinder pressure to push them to cylinder walls, pure material pressure is not enough.
You do not need high rpm but rather high load. Make few 3rd or 4th gear runs from 2000 rpm to say 5000 rpm, that will give rings good pressure and you will not need to rev the engine...

Spot-on advice!!!!!

Make MANY WOT runs in higher gears, cooling the engine between one.

[Neffets]

Did leak down test today, all cyl within 4-6% on a cold engine, all leakage can be heard through oil filler.
But I might see my problem, I can only get 170F on the engine, the temperature here is around 40F, and that is with a spirited drive. So maybe that's why it takes so long to break in the rings?
Can the engine thermostat be adjusted? I don't even have a front mounted oil cooler.

[snbush67]

Originally Posted by snbush67

Break In Secrets--How To Break In New Motorcycle and Car Engines For More Power

Really read the information this guy is sharing, it echoes the run it hard advice you are hearing from others.

[safe]

Originally Posted by Neffets

But I might see my problem, I can only get 170F on the engine, the temperature here is around 40F, and that is with a spirited drive. So maybe that's why it takes so long to break in the rings?
Can the engine thermostat be adjusted? I don't even have a front mounted oil cooler.

No, but at 170 the thermostat is just starting to open so I doubt it would matter.
170 is fine, remember, these engines wasn't just made to run on the track and in hot weather, it can also be used in sub zero climate. At low temperatures the oil takes a long time to get "warm" if it does at all.

Get out and drive the snot out of it, it's MUCH more important and if you drive it hard temperature will go up.

[txhokie4life]

Originally Posted by Steve@Rennsport

Spot-on advice!!!!!

Make MANY WOT runs in higher gears, cooling the engine between one.

I've been told not to lug the engine -- but to change RPMs a lot and to allow for engine braking when possible to really seat the rings properly.

We tend to keep the RPMs below 4K until 500-1000miles, but we don't baby it either.

M

[Mitch1]

I'm in same boat. 200 miles on engine. Has good power and doesn't smoke but I can smell the oil burning through exhaust. Checking oil level Sunday, noticed whiff of smoke from fill tube.
Seems like 2 camps of thought. The WOT camp and the take it easy on the bearings camp. I've been taking it easy. But now I think I'm going to the WOT side. Keep us posted on your progress.

[cgarr]

Are you sucking oil up into the intake for some reason?