Topic: Exactly how bad is this? chipped combustion chamber...

[madScientist]

So I'm going to preface by saying I'm an idiot. I was trying to remove the valve guides from a 750 F2 head using a punch and a hammer. In the process of beating on the guides, not only did I shatter one, but I managed to chip the combustion chamber around it. I stopped working on the other guides cause I dont want to f it up any more...best leaving it to professionals.

So my question...is this ruined or can i still use it? I was intending to send it out to have porting and polishing done...would this be repairable? Should I not be so freaked out?

I feel like an a$$

[lucky]

It could be TIG'd after it is cleaned. Not a problem.

Picture is not very good but it may not need anything. Just a little blending.

[madScientist]

Thanks! Thats very re-assuring. I thought for sure I'd ruined the head. I'll try to get a better picture but the chip isn't super deep so it might be able to blend like you said. I'm more angry with myself. I knew better but tried it anyway...

[754]

 drill the tops off and drive them the other way..far better method..

[madScientist]

754 --

Are you saying drill the valve guides out? So crack the tops off and then run a drill bit roughly the size of the guides through?

[madScientist]

Added better pictures.

I think it might be able to be smoothed out...we'll see i guess

[754]

Most guides have a groove or relief, right where it seats on the head . drill about 75% of the size of the guide, just past the groove. Give it a sideways tap, top breaks off.
 Then use driver to push guide into the port. Best way is to mount a pin that locates the guide or a fixture at proper head angle in a drill press.
 Guide holes always get lines in them pushing the other way, no matter how clean you try to get them.

[FunJimmy]

If you're sending the head out for porting, leave the guides in and have you're head expert do all the work. Better yet send the head to MRieck and he'll send it back in perfect condition.

[madScientist]

I have been in contact with Mike and will be sending it to him for his magic.

I'm leaving the head alone aside from cleaning it. Kinda wanted to get the guides out to make it easier on him but i'm not going to risk messing anything up further.

[FunJimmy]

I have been in contact with Mike and will be sending it to him for his magic.

I'm leaving the head alone aside from cleaning it. Kinda wanted to get the guides out to make it easier on him but i'm not going to risk messing anything up further.

I can't speak for Mike, but it's typically better to allow the expert to perform the complete service.
That way the liability for the work rests with the expert who performed it. Mike will also have methods and experience re & re-ing  guides that you may not.