454 oil consumption - BAD

[80goldenburb]

seems after searching around the net, that my Burbs powerplant problem is a rare one. or possibly just created from non experience.

Well here goes. My '80 suburban has an L19 (tbi 454) as I scrubbed the block with a toothbrush behind the alternator and got the production code that translated into sept 9th, 1991. I assumed this was factory block minus the obvious edlebrock carb/intake. Got curious one day and pulled the valve covers to find the casting 14097088, which comes out to be GM Performance's 454/502 HO heads. frankenblock lol! Now onto the problem. The motor burns a quart of oil every 80-100 miles. i know for a fact on multiple 500+ mile roundtrips, it'll be full at the beginning and then BELOW the "Add Quart" on the dipstick. Could it be the piston rings? I suspect this since my spark plugs are oil fouled when I checked earlier yesterday.

 

[yevgenievich]

Does it smoke on start up? Could be valve stem seals and/or blocked pcv valve. Leak down test will give a good idea of where oil is coming from.

 

[PrairieDrifter]

Do a compression test too

 

[80goldenburb]

Does it smoke on start up? Could be valve stem seals and/or blocked pcv valve. Leak down test will give a good idea of where oil is coming from.

it used too. it was a light grayish smoke. but sometimes light thin black smoke. that ended since I put half quart of trans fluid at the crankcase. now it just smells of burn trans fluid out the exhaust but no smoke.

 

[yevgenievich]

Should be blueish tint smoke on start up if valve stem seals are bad. Best would be to do a compression test followed by a leak down test. Also putting a vacuum gauge on the engine can give some info on the shape of the valves and rings.