M20 valve stem seals

[parkin10]

Is it possible to do them without taking the head off
Cheers

[Brianmoooore]

It's possible, but not necessarily easier.

[maxfield]

In a word, no. Possible but it's easier to take the head off.

[pacerpete]

A temporary fix at best. If the valve seals are worn / hardened, you can be sure that at best the exhaust guides will be very worn.

[parkin10]

Thanks for your replies
I had the head off approximately 7 years ago
the engineering shop said at the time the guides were serviceable and to leave them alone trouble is I used the cheapest nastiest gasket set to put it back together suffice to say that decision has bitten me more than once. Twass mi own fault for been a silly Tight sod
Today the only part of that gasket set left are the stem seals and yes I know it only going to be a stop gap measure but I thought about changing them too as I think they will have gone well hard by now
any way all ways use good quality parts do the job right and you'll do it once! Unless your a silly tight sod like me and then you can go chase gremlins for years

[Brianmoooore]

If you're determined to do it, there are two ways of keeping the valves firmly in place while you change them.
One involves turning the crank to lower the piston in the cylinder being worked on, feeding thick string in through the spark plug hole, then turning the crank to bring the piston up, compressing the coiled string against the valves.
Method two is to set the piston near the top, and feed compressed air into the cylinder via an adaptor in the spark plug hole. The fitting from a leak down tester is ideal, a modified compession tester can be used, or something can be bodged from an old apark plug with the ceramic smashed out.

[parkin10]

Thanks Brian your your input is always appreciated
I was thinking of electrical flex not string if I can move the rocker arms out the way enough
Just as a put me on till a proper rebuild can be afforded