Outer Limits 4x4 Board

Ok, long story short:

My '91 Sierra (just purchased) is chewing through a LOT of oil (we're talkin' >1.5L in 1000km!). It is not leaking anywhere. I have not seen any smoke, but was told that there were small puffs of blueish smoke under heavy acceleration. There is oil on the air-filter (but no where near 1.5L worth), so its coming back through the carby!

Please help me with a diagnosis (could it be a rocker-cover gasket?)

Thanks guys
-Ian-

How many kms has the car done? Does it blow smoke on start up?

mine uses 1/2 litre on bush trips around 200k cheers ron

Back in the early eighty's 1 litre / 1000Klmtr's was acceptable use, not sure what it is these days.
The oil in the air filter and blue smoke on acceleration is an indication that the rings are worn. The oil in the air filter will be from the engine breather probably due to excesive sump pressure (compression blow by) and the blue smoke is from oil that gets past the rings and gets burnt along with the fuel, a compression will tell if the rings are worn. If you only had the blue smoke it could have been valve stem seals but seeing that you have oil in the air filter as well it's more than likely rings.

Mine used to drink nearly more oil then petrol and blow alot of white smole when i gave it to it! I went to change piston rings and the lot but it was too far gone soo i got a second hand motor for $300 and now i can get up to 100 in a bout 3 minutes instead of 10 Sorry but it might be the bad news that you didn't want to hear.

Or maybe it's something completely different.

I have a 91 swb and travel 1000 k's a week to and from work, i use no more than half a litre per fortnight, i found a build up of gunk looked like oil and water mixture in the breather hose to the air filter. I usually clean it out once every couple of weeks.... still goes like a 2 bob watch.

Also depends on the amount of miles your motor has done and the speeds your doing up and down the highway. i would do a compression test that will tell you where you stand.

The car has 161,000km on the clock.

well I guess a new engine was always on the cards if the schmit really hit the fan...

I'll work on it for the time being - compression test is first on the cards

any other suggestions to look at and discount would be great.

-Ian-

try the valvestem seals mine were shot and it was using a shiteload of oil is it blowing smoke ?? or if you sit there idling for a bit and when you take off it blows a shite load of smoke my2c.iv got a set of valve stem seals spare if you would like them $20