Oil Consumption

[pablorg]

What is considered "normal" oil consumption for an AMC 360 rebulit 5 years ago and with about 20.000 miles?

I just had to put 3 quarts of oil from the last oil change which was Nov 15 (1900 miles ago).
I don´t see blue smoke on my exhaust....

Please help. Thanks!

[jeepsr4ever]

Pablo check the rear main seal. You may laso have a leaky oil pan plug, rear main seal or even a oil pan seal. I would hate to think its rings at this point.

[BREK]

3 quarts in 1900mi seems rather excessive to me. I would start with doing cylinder leakage tests, and maybe compression test, check intake for leakage. Are you sure it's burning and not leaking though? May not leak when sitting, but could leak when engine reaches operating temp, look under the vehicle for wet spots.

[dwg86]

Do you have the valley pan intake gasket? if not you could be sucking oil thru the pcv valve. I removed the pcv valve fron the intake and machined a plug. I put the pcv valve in the valve cover between the 2 and 4 cylinder rocker arms with a baffled pvc grommet from Moroso. No more problems.

[pablorg]

Do you have the valley pan intake gasket?

Yes, I do have the valley pan intake gasket. I recently changed the PCV Valve also...

[ironman_gq]

1 quart every 1000 miles is considered normal for most engines. I would check for a leak somewheres , probably the rear main or valve covers. those are the most common leak points but you should be able to see them if its leaking that much.

[pablorg]

I checked my spark plugs and they show what looks like some carbon deposits. I checked the compression on all 8 cylinders and I got from 115 to 130. I only see small leaks arround the valve covers... Should I just keep going and checking the oil frequently?

[tufcj]

My 360 does really well then. It was rebuilt about 30K miles ago, and uses less than 1 quart between 3000 mile changes.

I have to ask were the heads rebuilt, and what kind of valve stem seals were used. I always have the heads machined for positive style seals. If the valve guides are worn or the factory umbrella style seals were used, you can get a fair amount of oil consumption without seeing much smoke except at start-up.

Bob
tufcj

[pablorg]

The heads are new Edelbrock Aluminium Heads... Could it be that I need to re-tork them?

[ironman_gq]

1 quart per 1000miles is normal per specs. in reality many engines use much less than this but you shouldn't be worried if your engine does burn a little. 3qts in 1900 miles is definitely too much. If its not leaking out its probably being burned as it goes by the valve guides and/or rings.