thegrant

i have a 1998 ford f150 4.6l trition 160k, first; the only modifcation in the engine bay has been two new valve covers and gaskets. Second ( the problemm), please bare with me, recently it has been smoking more and more but it only smokes on start up (when the engine has been sitting for about a hour and has cooled off), It burns oil (blueish smoke) and goes through a quart about every two weeks ( -__- fml), now the wierd thing is if i keep the oil level high on it it smokes less, ( stupid truck), well if anyone has any ideas on what it could be please let me know.

Fabrik8

Check whatever type of PCV system you have on that engine and whether it's working or not.. Also take a look in the intake manifold and see if there are visible signs of oil from the vacuum lines coating the inside of the manifold. Keeping the oil level high can affect crankcase vacuum and some other things that can affect oil entering the intake system, but the smoking less may just be a false positive.

I'm assuming it probably smokes during normal operation and not just startup, but the rate it consumes during normal operation is not fast enough to make visible smoke. It's not burning a quart every two weeks during only cold starts, that's for sure. With that amount of consumption it's most likely coming from one of the normal suspects like worn valvestem seals or bad piston ring sealing. Both can have different behavior depending on whether the engine is warm or cold; for the rings it's a matter of thermal expansion and oil viscosity, and with valvestem seals it's usually oil pooling against the valves while sitting still, and then slow/steady leaking when the engine is operating. That's a lot of oil consumption for valve stem seals though, so I'm discounting that theory.

Dough_Boy.

Never head of keeping the oil level higher to make it smoke less. It has a plastic intake right? If so they go bad a lot so check that out. Did the truck sit for a while not running? If so it could be valve stem seals. Same thing happened to my mustand. Obviously different engine, but I burned about 2 quarts every couple of weeks. You just notice it among start up and none of the time after.

thegrant

thank you to both. well the guy before me let it sit for a while im assuming now because everytime i try to talk to him he avoids the subject, well anyways no its not the plastic intake its the high rise aluminum one, and when i got the truck it had stupid like a head gasket or valve gasket leak stopper? in the radiator so yeah. so do yall think i should pull the heads and get new valve stems?

Dough_Boy.

Valve stem seals are under the valve covers. But it would be best to take it to a shop. You have to pull the valve springs off to get to them.

thegrant

well I kinda want to do it myself because im a autotech student learning about all this and i have a shop that i can work in and have free labor so could you tell me all the tools or tricks that would help or if anyone can?

Fabrik8

You'll want an air compressor adapter to go into the the spark plug and pressurize the cylinder so the valves won't drop, and you'll need the normal tools to remove and replace valvesprings. You may or may not need special tools to remove/replace the valve stem seals depending on the seal design and head design. I don't know the specifics of that engine so I can't say, but the concept is the same for pretty much any engine with the exception of needing some special tools sometimes.

Dough_Boy.

I believe they are just umbrella seals. So he shouldn't need any special tools for that.

thegrant

would it be better to get just the oem valve stem seals or go to aftermarket?, also what kind of adapter to pressurize the cylinders?

Dough_Boy.

Just a compression checker that you can hook an air hose up to.