Ugh - Newly rebuilt engine burning or leaking lots of oil

[tdskip]

The professionally rebuilt engine that I had professionally installed in the 1974 Tii either leaked or Bert a quart of oil over the last 254 miles. In other words since it’s been fired up it’s only traveled 254 miles and it’s already a quart low.

 

That can’t be right, and I’ve got oil on the exhaust pipe and drips under the car that are engine and transmission oil.

 

as far as I know I’ve made a concerted effort to break it in properly, can anyone think of anything that I might be missing here before I get my head around the edge and having to come back out?

 

thanks and hope everybody had a good weekend so far.

[Mike G]

you’re sure it was full when started? Including the filter?
 

Gravity effects oil so the leak is above the drips. If there’s drips on the exhaust manifold have a look at the valve cover gasket. Was the head skimmed? Did they skim the front timing cover the same amount? Pictures can’t hurt. 

[Son of Marty]

If your leaking/burning a full qt of oil you'd have a huge mess running off the engine, as above did your prefill the filter and check the oil level after a short run, leaks can be fixed if it's burning it it would be smoking heavily.

[tdskip]

Thanks Mike, I’ll try to get it on a lift tomorrow but no leaks from the top of the engine. 
 

When I checked the oil upon picking it up from the shop it was full just to be top mark of the dipstick, tonight it was at the very bottom mark. 
 

Appreciate the ideas.

[tdskip]

10 minutes ago, Son of Marty said:

If your leaking/burning a full qt of oil you'd have a huge mess running off the engine, as above did your prefill the filter and check the oil level after a short run, leaks can be fixed if it's burning it it would be smoking heavily.

I didn’t initially fill the oil myself as it was at a shop but it had been run and test driven prior to my confirmation it was at the top level mark on the dipstick.

 

I don’t see signs of any smoke, which is encouraging I suppose.

 

 Thanks for the follow-up.

 

(I am a bit gutted if I am being honest)

Edited January 18, 2021 by tdskip

[Son of Marty]

That's a lot of oil first check your dipstick tube make sure it's well seated some of the styles BMW used were funkier than others. So you are not seeing a cloud of oil smoke behind you as your drive?

[Mike Self]

Sounds more like leakage than burning.  If it was burning oil at the rate of 250 mi/qt, you'd be fogging for mosquitoes.  Quick test:  run the engine under load to 3500-4000 rpm in second or third, and let off the gas.  Smoke here = valve guides/stem seals.  Then let it idle for 30-40 sec, put it in gear and start out in first normally.  Smoke here = rings...and with only 250 miles, the rings probably aren't properly seated, so a little oil consumption would be normal.  But 250 mi/qt aint' normal.

 

I'd look for leaks per previous suggestions.  That'll be a lot easier to cure.  Couple of places not mentioned yet:  exhaust manifold studs, the rubber seal on the distributor neck, the oil pressure switch, even the oil filler cap.  

 

Check 'em all out and let us know whatcha find...

 

mike 

[tdskip]

Thanks for the on-going discussion. I don’t see any signs of smoke and did have a friend follow me earlier. Exhaust under the gearbox looks coated in tar, which I assume is my missing oil.

 

Top of the engine looks clean enough to eat of still.

Edited January 18, 2021 by tdskip

[stephers]

Rear main seal?      maybe they used one of these nes PTEF seals that don't use a spring in behind them.    Installation on those is very tricky and the procedure must be followed exactly on those     Personally, I don't like them 

 

Thanks, Rick

[2002iii]

First step call the engine builder and/or installer and ask them if this is normal. Next ask if they broke the motor in with break in oil? Did they give you any special instructions?

 

Then I would take the clutch cover off and see if there is any oil in the bellhousing, if there is its probably the rear main seal is leaking.

[2002Scoob]

I 3rd, 4th, or whatever checking the rear-main-seal.

 

Other thoughts would be that maybe they didn't prime the oil system properly before you initially checked oil-levels? 

 

6 hours ago, tdskip said:

tonight it was at the very bottom mark. 

 

Did you check right after shutting down, or was it given a few hours to drain/settle? 

 

Burning a bit of oil on a new motor is to be expected till the rings fully bed-in, and as I've found with my motor even a fresh M10 will still consume a fair bit of oil if you're used to more modern machinery. but that's indeed excessive if true.

 

If it were just a little bit low, there was no external leaks visible, and the bell-housing was dry, I'd recommend driving the piss outa' it be to see if things bed into place.

 

But since you paid a shop to build it and install it, I'd drive it back to them and drop the problem on their doorstep to fix. 

[tdskip]

Will pull the clutch cover, bad rear main leak crossed my mind too.

 

Thanks for all the ideas and considerations.

[irdave]

4 hours ago, 2002Scoob said:

But since you paid a shop to build it and install it, I'd drive it back to them and drop the problem on their doorstep to fix. 

 

Just thought it ought to be said again, that's all.

 

Edited to add; But do it with a smile.  Things go sideways sometimes, chances are they didn't do it on purpose. 

Edited January 18, 2021 by irdave

[M3M3]

if it ain't right, take it back.  don't try to fix yourself....shop can then blame you for the problem.

[tdskip]

Thanks for the follow up. There are two shops, the one that built it and th wine that finished buttoning everything up.

 

issue would seem to be with the engine builder, will contact them today.