Valve Stem Seal on GQ

[mike_beecham]

Boys

According to dealer - Valve stems seals on a 1991 GQ 4.2 Petrol 210,000kms. Blowing smoke on start up until warm (is this related to this seal anyway??) Engine is not running LPG.

What sort of drama does this job entail? Labour/cost wise?


Looking to purchase this truck. Or is it not worth it. Bit concerned as to why the seals have gone so early on in it's life or is it common?

Thanks,


Mike

[PGS 4WD]

Can be done on car, they can go brittle with heat and age and replacement may rectify the problem. It's also possible the guides are worn and replacing the valve stem seals will only provide a short term fix.
Some special tools are required to fill the cylinder with air and remove the valve sparing.

Cheers
Joel

[mike_beecham]

Thanks for that Joel.

The valves - would they be causing the smoke when the engine is cold at all?


Mike

[canuck]

Bad valve stem seals will give oil smoke on start-up from a cold engine or on acceleration after being left on idle a bit. A number of Toyota petro engines had this problem with seals going bad under 200,000 kms. Hadn't heard much about this from patrols. Unless it is a very good deal, keep looking.

[PGS 4WD]

I would probably refine that to say valve stems seals or guides will blow smoke cold start, at long idle periods and on decelleration, or when you take off just after a large decelleration or idle period. Generally smoke under constant load is rings. Valve stem seals leak under vacuum, rings under load.

Cheers

Joel

[ANDREWGQ 351]

You can use a rope cord into the cylinder, ensure both valves are closed, feed the rope into the cyl through the spark plug hole and then rotate the motor until it gently jams and holds the valves up. Then you can remove the springs to change the seals.