Snapped Bolt On Head

[philbey]

 

 

Basically i had the head "rebuilt" by a mate. He just cleaned it up, new valve stem seals, levelled the attaching surface. But when i got it back, he hadn't taken that plate off the back. So i have no idea what he actually did to it, but it cost me a carton of piss so i'm not complaining (god how bad does that hole look :( )

 

Actually, that looks pretty good, there's some shit around there because of the old gasket etc but the actual waterjacket looks pretty good. Nothing a bit of gasket remover and a paint scraper won't clean up.

 

Now how the hell do i fix this.... I've looked into some of the reverse thread extracting thingies and they seem the go, but its not going to be very easy cos its snapped about 2 mm into the hole ...

 

Your best and easiest bet would be to try easy outs. These are only mild steel bolts, so you can drill it easy and you should be able to pull it out easy enough. Now that the bolt is snapped there is little to no load on the thread so it should wind out easily enough.

 

Just get some ezy outs and very gently drill a hole down the guts of the bolt. MAKE SURE YOU USE THE CORRECT SIZE EZY OUT.

 

Most ezy outs snap because people use one that's too small.

 

Also, before you wind it out, get a blowtorch onto the area around the broken bolt. Aluminium expands more than steel, so even raising the temp 50-60 degrees will make a big difference to how easily that bolt comes out. You shouldn't have too many issues doing this on a built motor, just apply light heat to the spot, just get it so it's too hot to touch.

 

EDIT - I reckon you'll be fine to remove the head and reassemble without upsetting the gasket.

 

I know for sure that most of the Early KE30's have one of their heater hoses coming off there.

 

3K bigports have a welsh plug there.

 

The hole on the back of the head is from manufacturing, it's where the internal core of the mold is secured into the outside cavity of the mold, that's how they cast the internal details of the water jacket etc.

 

Edited November 7, 2010 by philbey

[RainWarriorDregs]

Thanks for the advice guys. I got it out, tried an easy out but the bolt snapped when i was undoing it so it was pretty well seized in there and the easy out didn't work :(

 

So i got a 3 mm, 4 mm and 5 mm drill bit and a 6 mm tap. I center punched the shaft of the broken bolt a few times then slowly worked it with the drill bits and then it pretty much collapsed on itself. After that i ran the tap into it a few times back and forth and cleaned the thread and she was good to go.

 

 

first time i've ever done anything like this :dance:

 

yay for learning!

 

Cheers again guys

[Tally]

did the same thing on my head not long ago, got head reconditioned and got them to take the bolt out and weld up the head so got rid of the plate.

 

Much nicer and don't have to worry about any leaks in that area now :)

[RainWarriorDregs]

yeah i was thinking about the welding up, but i'm going to save up and get another head reconditioned with new valve springs and valves and stuff because i'm currently running a camshaft with more than 400" lift, so i'm pretty sure the heads gunna cark it in a while. So while i'm getting the rest of the stuff done i'll get that hole welded up..

 

 

oh yeah, i put a new gasket behind that plate and sealed it with the Ultra Black sealant, or whatever it is, i was told this will handle the temp and the coolant runnig past the back of it.

[philbey]

honestly you don't need to have it welded, clean the mating faces off properly and use sealant and a new gasket like you've done, then replace the bolts with new ones and it'll be another 30 years before you have to worry about it.

[RainWarriorDregs]

oh ok philbey, i guess i'll see how it goes.

 

Damn, didn't put new bolts in either.

[philbey]

You can still swap the bolts out, just do it one by one if you've bolted the plate back together.

 

The bolts most likely snapped from corrosion, so new ones will be more reliable.