Valve stem seals. Glue them in ?

[Paul99]

OK.  Sorry. Last time re these things !
Put new ones on again. 2 popped off almost immediately.  They were clean new dry etc and used loc tight. 

So should I glue them. Nail them. Weld them on or what Suggestons please.!

[Benz Dr.]

I take it your car is a 230SL? It can be very difficult to install them and not have them pop off. I put them on bone dry. Any lube, oil, or anything that will make the seal move won't work. And then they can still come off. 

[Tyler S]

When the machine shop installed the guides on my head, they lightly knurled the outside circumference of the guide where the seal is. This is on a 250 but im sure could be used on a 230. They said it removes any chances of the seal popping off. Maybe there is a tool that could be used for doing this with the head on the car.
Here is a pic installed. You can barely make out the knurling on the brass colored guide portion.

[stickandrudderman]

knurling is the way to go where viable, otherwise I use superglue.

[Paul99]

Many thanks.  Will try roughness inside the seals and on the guide tops and use araldite glue. Leave 24 hours . See what happens this time !

[Shvegel]

I think Stick has the right idea with Superglue or Cyanoacrylate glue.  There are Cyanoacrylate glues that are very slow curing until sprayed with an activator which would be perfect. 

[stickandrudderman]

don't use araldite, it's too bulky and the chances of excess glue being squeezed over the top of the guide are high.

[Paul99]

Going to go with superglue. Noticed it seems work best with plastic as well. 

Thanks for the suggestions.  Hope it works this time

[Paul99]

OK, I had them sorted - so far at least. 

Had the old seals removed, each valve guide roughed up around the top and had the seals refitted with super glue.  Took forever as each one needed to be checked that the glue went only where it should do  Used a 2 pack system, glue and hardener.

One thing i learnt is that the seals seems to be made of some kind of  polythene. Many glues do not stick polythene at all.  Araldite for example does not.  So i think super glue is the only thing, and even some super glues do not stick some plastics.  Found one that does.  Seems to be working. 

This is the kind of glue we used. https://www.youtube.com/watch?v=aZlKvxBRNsA

Hope that helps. 

Paul.