1G Stuck Valve Guides

[thejollyrancher]

Hey,

Im trying to replace my valve guides and they will not budge at all. Ive tried an air hammer, a normal hammer, heating up the head in an oven, spraying penatrant, but NOTHING. The only option I can think of is drilling them out myself as no shop anywhere near me drills them out. Is there any good way to go about drilling them out? or is there a better option?

Thanks

 

[DSM IN MN]

Well first off there is a certain tool made to be used in an air hammer for guides. They vary by guide size/head. Secondly they are to be pressed from one direction. I can not for the life of me remember the direction though.

If I had to say, it is from the valve cover side to combustion chamber.

 

[steve]

The Overhaul Manual explains that the old guides are pressed out from above towards the cylinder head gasket surface and once the new holes are bored for the oversize guides pressed in from above with the special tool that limits the depth of the guide.

 

[arrowhead]

Yes , there is a better option:
Take it to a machine shop, this is a precision procedure, if you persist on doing it yourself you will ruin the head for sure.

 

[SrKegler]

Agree with taking it to a machine shop. The seats need to be recut anyhow.

 

[ColtiXim]

Take it to a machine shop, this is a precision procedure, if you persist on doing it yourself you will ruin the head for sure.

My "French" machine shop has killed my head, bad method.
Cold head and press, result : three guides playing up and down after only 2 miles.
My build is stopped from December, insurance fight since this story.

Please use a reputed machine shop for every work on our motor ...

 

[Gerg]

http://www.dsmtuners.com/threads/how-to-change-valve-guides-in-a-4g63t-head.341218/

Looks like Dale presses them out from the combustion chamber. I would stray from heating the head in an oven though, you don't want to warp the head in this process.

 

[thejollyrancher]

I have a makeshift tool I made that should do the trick but it doesnt seem to be enough. Ive been trying to hammer it out that way and Ive been getting nowhere. I tried again today and ended up cracking up the guides and they still didnt budge. I just picked up a new head.

 

[BogusSVO]

If the guides do not move with the air hammer, the head needs to be set up and leveled and be drilled out.

It sounds like the head has been thermal cleaned a couple times and locked the guides in place.