How Screwed Am I? A Freeze Plug Story

[rebelyell]

I'm just gonna go ahead and say it.

I drilled into the water jacket in my cylinder head trying to fix yet another valve cover bolt. I went to drill it for the same size to clean it out a little, and as soon as the drill touched the bottom of the hole coolant started flowing out. 

Once the coolant stops pouring out, can I tap it for the next size up, goop it with some RTV and let it ride or do I need a new head? My poor mechanic skills are really taking the fun out of this car.

[RUNCHARGER]

It sounds like you could make a stud to go in, apply sealer to the stud and thread it in, then use a nut to retain the valve cover? Pipe thread obviously would seal better but this should hopefully work.

[1 Wild R/T]

I agree, don't go oversize if you don't have to, it only complicates things...  Tap it clear into the water jacket, double ended stud & sealer of your choice...My choice would be   https://www.amazon.com/dp/B0030MTX5I?tag=vs-auto-insert-amazon-20

[Shane Kelley]

 
Put a stud in with teflon tape. No big deal.

[rebelyell]

THANKS! I'll be getting a stud tomorrow. Probably have to go up a size, but hopefully not.

[Burdar]

You could also run a short set screw into the bottom of the hole to seal it. Then run your regular valve cover bolt.

[Roadman]

You could also run a short set screw into the bottom of the hole to seal it. Then run your regular valve cover bolt.

  Yep, what I would do.   

[rebelyell]

You could also run a short set screw into the bottom of the hole to seal it. Then run your regular valve cover bolt.

Well, that's genius. I may try that. But with my luck and this car, I'll run it too far and put it in the water jacket. Stud might be my safest bet, haha.

[RUNCHARGER]

Try not to use a thicker stud. Not much cast iron material around it.

[cudabob496]

and of course put in some stop leak, which I have done to prevent
leakage out of header bolts.

[rebelyell]

So I got it "fixed" but it didn't go smoothly.

I bought an 8mm drill and tap to fix both holes. I drilled the rear one fine. Tapped the rear one without problem. As for the front one with the coolant problem, I remembered "drill and tap straight through" so that's what I did. Stupid me didn't check to see that the hole bottomed out on the freeze plug. Drilled straight into that bastard. I only knew this because of the coolant that was now flowing from the front of the head. Figured that'd be far enough and stopped drilling. Tapped it fine. Waited for the coolant to stop flowing from the front of the head, dried it off and applied a ton of gasket sealer to the front. No idea if this will work, but I'm giving it a shot. I was able to replace both bolts with 8mm socket head cap screws. I put teflon tape around the front bolt. Don't ever, ever, eeeeevveer plan on taking this valve cover off again.

Don't know if that'll fix the leak. Don't know if I should have put gasket sealer around the paper gasket. Probably should have, but with as many problems as I've been having, I wanted to make sure it was going to bolt up first. Exposed rockers were already starting to show rust. Might take it apart again tomorrow and apply RTV all over the damn place.

[Cuda Cody]

Man, you're just having all kinds of bad luck with that head.   

[rebelyell]

Man, you're just having all kinds of bad luck with that head.   

No kidding. I have bad luck in general.

[Chryco Psycho]

 

[rebelyell]

I know.. I know...