I checked my oil consumption when driving from Clearwater back to Miami Beach. I drove 280 miles and used 1 quart of oil. I heared that HP engines consume more oil than regular engines but 1 quart for approx. 300 miles seems a little high. My 80' Duntov for example gets well above 1000 miles per quart of oil..

Is it possible that my rings haven't seated perfectly after 1500 miles or is such oil consumption normal for such an engine?'

:cheers:

Olivier


[Modified by GrandSportC3, 11:37 AM 7/22/2002]

 

I have had that same thing happen on new builds it should get better the more you run it. Strange thing is that it does seem to happen to my motors that are built to make horse power. I think the better the rings , pistions, ECT,
the longer the breakin seems to take. when we do a stocker they seem just fine from day one.

 

my zz4 is not as mean as yours but it does not use any my 8.1 hd uses about 1qt per 3000 miles and my ls1 does not use any

 

I hope that you are right and it's only a matter of time...

:cheers:

Olivier

 

The ZZ4 isn't really a radical engine. I know that the GM crate engines hardly consome any oil.

:cheers:

Olivier

 

Normal oil consumption is negligible, zero, zip, none, not noticeable. New rings that "haven't seated yet" should only be allowing a very small amount of oil either that which fills the honing grooves, or that are a bit oval compared to the cylinders and allowing a micro thin film to get by. UNLESS, you have your PCV plugged and are allowing exhaust gases to build pressure in the crankcase and forcing oil out. OR, one or more rings could have been broken, or the rings of too small size thus having too large of a gap. A compression test will uncover damaged rings (as long as the valves are sealing good).

Significant oil consumption (if there's none leaking to the outside, or into the coolant) is usually due to valve stem oil seals not installed properly, or damaged during install, or worn/cracked and otherwise not sealing properly. Removing the valve cover and inspecting the seals will uncover damaged or otherwise non-functioning stem seals. They can be replaced without taking the engine out by replacing them on the #1 cylinder when it's at TDC after compression stroke so that both valves are closed all the way, then turning the crank to the next cylinder in the firing order until they are all replaced.

I've never seen any oil consumption from any of the engines I've rebuilt, but then again I soak all my internal parts in oil before installing them, so nothing gets started dry.

 

Well - the oil system was primed before the engine was initially started...
I had the same oil consumption problem with the 450 HP engine on my 69(sold). This engine had TRW forged pistons and initially consumed 1 quart /100 miles :eek: :eek: :eek: . After 2000 miles the oil consumption went down to 1 quart in 250 miles which still seemed very high... I'm having approx. the same oil consumption on my current engine and I wonder if this has something to do that both engines are pretty radical...

:cheers:

Olivier

 

The higher the engine's performance, the more you want to control the oil consumption. Oil in the combustion chamber makes the engine very detonation prone. There sould be very little oil consumption even in a new engine. The only exception would be for an engine using chrome-faced rings, which take a while to seat, but even then you wouldn't consume that much oil. If you're experiencing that level of consumption, you have a problem in the rings, valve guides or seals or you're pulling oil though the pcv. You can't use the other engine with a similar problem as a historical reference as to what is right or to be expected since the vast majority of engines to not exhibit this problem.

 

I got about 100mi/qt when I got the engine built. Found out it was due to leaking valve seals. These were Dart II heads with umbrella seals & cast iron valve guides. You couldn't see black smoke but the oil went anyway. After a valve job, bronze valve guides & teflon seals, oil consumption is down to about 2000mi/qt.

 

I went round and round on this one after my 383 was built. Did some re routing of the PCV setup and this helped some. I eventlually found the main culprit was the intake was not tight. This is
something very easy to check and it could make a big difference.

My initial consumption was 300mi/qt and now its somehwere between 1000 and 1500/qt. big difference for just tightening some bolts..

Chris

:flag

 

Is it possible that brand new DART Iron Eagle Heads with bronze valve guides and seals could have a problem??? Everything on the engine (exept the block wich is bored .30 over) is brand new...

:cheers:

Olivier

 

Well - I have brand new DART Iron Eagle Heads with bronze valve guides.... I don't think that there's anything wrong with them... I will have the engine pressure tested to see if there's a problem with the rings...

:cheers:

Olivier

 

What's the correct torque for intake bolts??

:cheers:

Olivier

 

i noticed a puff of smoke from the left yesterday; that was the same side that smoked when i changed manifolds; so this morning i gave it almost another 1/4 turn. with a hammer :eek: on a box wrench, not a torque wrench. got to cinch it down (taps not wacks :crazy:

 

:eek: :eek: :eek: is there no risk cracking the intake around the intake bolt if you tighten them so much???

BTW - I will tighten my intake bolts when I get home... Will see if it makes any difference..

:cheers:

Olivier


[Modified by GrandSportC3, 3:07 PM 7/22/2002]

 

My 650 HP 440 Mopar uses no more or less oil then the average street motor.

 

The GM crate motor in my GMC truck has pitiful valve seals and smoke at startup 95% of the time.

 

i'm not sure it is "so tight".
the bolts have sealer on them and need to be tapped or they won't turn, since the sealer is not fresh. the idea is to tighten it 1/8 to 1/4 turn; the gasket has some "give" in it. start with center bolts; i did not get all the end ones(lazy) coil was in the way, but this was the 3rd time
i never cracked an intake, but there is always a first time :lol:

 

I won't have this problem with the coil. My HEI has a internal coil!!!

Thanks for your info!!!

:cheers:

Olivier


[Modified by GrandSportC3, 7:44 AM 7/24/2002]

 

I tightened all my intake bolts today.. I was able to turn some of them (the ones close to the firewall) more than 1/2 turn.... I hope that this will reduce my oil consumption... I don't think that I have any excessive blowby because there's no oil on the valve covers around the breather...

:cheers:

Olivier