smokey mitsubishis

[Amb]

Mitsubishis are infamous for blowing smoke/burning oil. Why is that, I never did find out. My guess is that its shoddy valve guides. Thought they would have ironed out the problem over the years, but I'm now starting to see later models with the same problem. May be they don't wont to completely solve the problem.

[Coldamus]

It is the valve stem seals. Relatively easy to fix and low cost if done yourself. Say $30 for seals, $20 for rocker cover gasket/s and $30 for a valve spring compressor.

The seals harden over time but are usually good for at least 150,000 kms. I just replaced mine at 265,000 km and totally solved the problem.

The later V6 engines (3.5 litre and onwards) use a different material for the seals that is supposed to eliminate the problem.

[dazzler]

Its valve stem seals if it smokes on start up or off idle, rings if under acceleration.

[dazzler]

[quote=Coldamus;579727]It is the valve stem seals. Relatively easy to fix and low cost if done yourself. Say $30 for seals, $20 for rocker cover gasket/s and $30 for a valve spring compressor.

[quote]

Head on or off

[wheelinround]

[quote=dazzler;579766][quote=Coldamus;579727]It is the valve stem seals. Relatively easy to fix and low cost if done yourself. Say $30 for seals, $20 for rocker cover gasket/s and $30 for a valve spring compressor.

Head on or off

Makes you wonder why NRMA classed them car of the year doesn't it, maybe it was this was the car they were doing roadside asistance to the most.
Or was it the great deals they had done for companie vehicles.

Their truck motors sufered the same fate with blowing oil.

[Bleedin Thumb]

I hate those noisy hydraulic valve lifters. Ive replaced mine twice in the Ute.
Besides a few irritations its been a very reliable car......maybe I'm just comparing it to the Range Rover!

[echnidna]

So are they reliable cars apart from the valve stem seals?

[Bleedin Thumb]

So are they reliable cars apart from the valve stem seals?

I'd say indestructable. The early magma's had bad transmissions but generally pretty reliable ............also about as exciting as watching grass grow, I wouldn't buy another......lifes too short to drive boring.

[DavidG]

Leave the head on to replace the seals.

Modify an old spark plug to take the compressor hose and use compressed air to keep the valve closed.

Lever the spring down and remove the collets.
Remove the spring and replace the seal.
Put the spring back and compress it.
Put the collets in.
Repeat for each and it should last another 100k or so.

Half a days work.

Would much rather have Mitsubishi oil down the valve guides than ....... oil past the rings trick.

[dazzler]

David

Do you suggest doing each on Top Dead Centre TDC just in case

[DavidG]

It will finish at bottom dead centre what ever you do so keep the fingers clear when the pressure is applied.

ps: If you can not build up enough pressure then the rings are shot.

[Amb]

Thanks for all the info, that's good news, so our old 1989 Mitsy is not dying from worn rings. After all, its only done 150,000 km.

DavidG, thanks for the info, not removing the head etc, makes the job much much easier. I l did a search and found that using your suggestion, if you don't have a compressor, you can simply stuff a good length of nylon rope in the plug hole (of course don't lose the end!), then move the piston up, so that the valve will be held up by the rope. How's that sound Dazzler? Simple huh?

[dazzler]

You will need a spring compressor that bolts to the top of the head to depress the springs as opposed to the type that you use when the head is off.

never heard of the rope trick.....sounds interesting

[Gra]

never heard of the rope trick.....sounds interesting

The rope trick is a beauty. even used it to help remove a stuck head. Dont ask.....

[Coldamus]

I don't have a compressor, so I used the rope trick and it worked well. It took me about 4 hours but I was being ultra careful.