PDA

View Full Version : Replacing valve guide seals



Odyssey
22-10-2008, 09:27 PM
Does anyone know if it's possible to replace the valve guide seals on a '90 passat 1.8 GT (8 v OHC) without removing the head?

TIA

Alastair

adamss24
22-10-2008, 09:32 PM
I do think its possible without taking the head off... I know that it could be done with a air coupling to the plug wich can hold the valve in the closed position then you can remove the valve cotters with a special valve compressor and remove it in situ. However, i would not recomend it... Take your time at laping the valves in, fit a new gasket set and bolts and you wont go wrong !

kenney
22-10-2008, 09:54 PM
Hi You can replace the seals without removing the head.It is not a difficult job,i have done it many times.

Odyssey
22-10-2008, 10:09 PM
Wow Kenney, that's useful info, more detail would be appreciated, for instance, do you need to take the cam off? Do you need the compress the valve springs and remove collets, or do the seals just fit over the top?

Bear in mind this engine has done over 160k miles and has never been opened, even when the cambelt went, I managed to replace it without removing the rocker cover. It runs very quiet and smooth, but it's been burning a little oil on tickover (though none on overrun) for a while, but now the plugs have started oiling up, so it seems the seals could do with changing. I know I should probably do a proper top overhaul, but I don't have the time for anything but a quick fix at the mo.

Any guidance will be greatly appreciated.

THX

kenney
22-10-2008, 10:30 PM
Hi You must remove the camshaft. Send your e-mail address and i will send the info,Adams 24 mentioned how to do it.

Odyssey
29-10-2008, 01:37 PM
Update - took the rocker cover off for a look, and I was reminded by the blocked breather mesh of having to clear it before (about 10 years ago)!

The problem then was not oiling up but uneven idling, and I was pointed to this by an old VW mechanic (who I believe has since gone to the great workshop in the sky).

The blockage was causing a build up of pressure in the rocker cover, forcing the oil down past the tappets into the engine and oiling the plugs

Because the mesh is welded into the rocker cover, you can't get at it to clean it, but his tip was to fill it (the mesh section, not the car) with petrol and light it, and this burnt all the black deposits off, clearing the breather.

I didn't like the idea of this (I might be grumpy but I'm not suicidal) so I refined it by using a blowlamp to heat up the mesh thoroughly till it's glowing red and it doesn't burn any more when you take the heat away. Let it cool, cleaned it all up and replaced it, cleaning the other filter on the rubber tube to the inlet manifold, which was very oily, and - ta da! no more blue smoke, and plugs haven't oiled up in the 200 miles since.

So maybe I'll get another 14 years out of it yet (see my other thread about starting probs)

A useful tip, so I thought it worth passing on.

Alastair