Leaking valve seals

[mtchll]

Recently I have been experiencing a little bit of white smoke with a bluish tint after start and at idle. Once I start driving it goes away. I know I'm burning oil and i know its not my turbo/turbo seals and im fairly positive that my compression is good. I'm thinking its my valve seals that are leaking and need to be replaced.

I know people have replaced them before by themselves without removing the head. I was wondering about how much shops would charge to replace the seals and/or how hard it is to replace yourself. Any help would be great!

 

[JusMX141]

This job is hard enough with the head off the car- I can't imagine how difficult it would be with the head on the car.

If you drive the car too long with the seals leaking, the oil will run down the stem of the valve and burn / stick to the exhaust valve seat. This causes irregularities in the sealing surface, and will lower your compression ratio. This is exactly what was wrong with my '92 TSi FWD when I bought it...around 100psi on all four cylinders with a very tight bottom end.

If your car has high mileage (and it probably does if you suspect the valve seals are leaking), you're better off pulling the head anyway. Change the gasket, have the head resurfaced, upgrade to head studs instead of buying new bolts, have all of the exhaust valves replaced (the sealing surface WILL be pitted), and have the head cleaned / degreased. You will be much happier with the result.

 

[romeen]

I've changed valve seals with the head on a car. I actually don't think it's very difficult but it can be very time consuming since you have to remove the timing belt, camshafts and the valve train (except the valves) But you have to have the right tools to do it. Luckily I do.

To keep the valves from dropping down when you take off the springs, etc I use compressed air. I have an "air hold line" that attaches to the air compressor and the other end gets threaded into the spark plug hole of whichever cylinder you are working on. It continuously runs pressurized air into the cylinder to keep pressure on the valve to hold it up.

This is the spring compressor that I use.

GA317, Remover/Installer, Metric Valve Keeper

It's very fast and easy to use. It releases the valve locks and they stick to a magnet on the inside of the tool so you don't have to go fishing around for them. But it can be difficult to use if you have aftermarket stiff springs.

Once you have removed the springs you can pull the old seals out with pliers (I use a slender nose vice grips). Lube up the new seals and push them down over the valve stem using a deep well 11mm socket.

Then reassemble the head/valve train components, new valve cover gasket and re-time the motor.

 

[BogusSVO]

If your asking this question, I will assume (not a good word I know) that you do not have the tools/equipment to do this.

I will have to say +2 to what Jusmx141 says

pull the head and send it to a good machine shop, have a valve job done, and have the head milled.

 

[mtchll]

Okay, thanks for the input guys, I really appreciate it!

But to what Jusmx141 said, how much do you suspect something like that would cost at a machine shop?

 

[BogusSVO]

a full valve job in my area is $160 and surfacing is $45
plus parts and tax
prices can and will vary depending on what shop and what part of the country your in.

when you take the head in take the valve stem seals that come in the gasket set with you.

before you decide on a shop to work your head, you need some more info, both from here at Tuners and from the shop you thinking of using.

NOT all shops have the equipment and/or knowlage to work your head properly.

you need to ask the shop, whet equipment they use to cut the seats, and also what equipment will be used to surface your head.

read all this....
http://www.dsmtuners.com/forums/articles-engine-fuel/303225-engine-machine-work-explained.html

http://www.dsmtuners.com/forums/cyl...0613-why-not-let-your-head-belt-surfaced.html

valve springs may be weak on your head also, so ask the shop to test yours...
http://www.dsmtuners.com/forums/newbie-forum/341287-how-test-valve-springs.html

here is spring info...
http://www.dsmtuners.com/forums/newbie-forum/341209-4g63t-valve-spring-info.html

you may want to do this oil mod before the head is surfaced.
http://www.dsmtuners.com/forums/newbie-forum/341028-4g63t-head-oil-port-mod.html

it is alot of info, but the more you know the better your project will be.

 

[YZFR1]

Anyone, that has had leaking valve seals in the past. Did that make your spark plugs fouled up? Thank you

 

[haswesley]

Depending on the amount of oil passing the seals, it can foul spark plugs.