M10 tap for damaged head threads
 

I have been needing to do multiple motor test fits, taking it in and out of the cross member. Also moving it around my two car garage multiple times to get it out of my way.

Today I went to move it to another location yet again in the garage to get it out of my way and noticed the bolt for the chain sticking out at an angle like this.

http://i1206.photobucket.com/albums/...7/DSC_0592.jpg

Have no clue when or how the bolt backed out that far.

Anyone think I could clean this up with a M10X1.5 thread tap and get away with it? Not that many threads were damaged.

http://i1206.photobucket.com/albums/...7/DSC_0598.jpg

http://i1206.photobucket.com/albums/...7/DSC_0595.jpg

http://i1206.photobucket.com/albums/...7/DSC_0594.jpg

I would grateful the head did crack right there...I think you will be fine running a chaser in there. The bolts for the PS pump bracket go further in the head and are not torqued very tight.

Ahh snap, you did it to both sides?

No, just on one side. Back side of driver head.

Ahh. The back side? I take it, you're not even going to use that hole for anything?

No not really, but I have to use it to drop the motor in. I don't own a
Valley cover lift plate (guess I should invest into one). If I tried to bolt the
chain to the back passenger head it would come into contact with my a/c, heater box on firewall while trying to drop it in.. Already had to put a notch in it for the coil pack brackets.

Update

tried to run a tap through it the best I could, but to no success.

Bolt threads in but wiggles around a lot by just moving it with my hand.

Was thinking about trying to drill it and tap it for M12 bolt? I'm not sure about how much meat there is to work with in that location to step up to a M12 bolt in just that spot.


This bolt location is a non issue with the motor in the car, but is a issue with getting the motor in and out of the car as this is a spot I like to attach my load leveler chain.

Plus my motor is set back, and is right up against the fire wall when placed in. Using any of the lower bolt hold locations is a bitch to get to.

Do it right, 10mm-1.5 Helicoil kit. And you'll have it for future repairs...

Thought about that, some reason I just never really been a fan of heli coils.

Guess it wont matter too much, just an spot to attach my chain.

Anyone use loctite on their heli coils?

GM uses nut serts for the repair of any block threads ........FYI

Was just reading up on "time-serts". Seem to be leaps ahead of heli coils.

I can not find anything though for a reasonable price, they seem to be pretty damn pricy for the kits.

Seeing as I have to drill the hole bigger for the "time-serts" or even the heli coil I figured I just go with M12 bolt.

if you took the heads off and took them to the dealer ......might be cheaper than buying the whole kit

Got a M12 tap in today and got it done. I probably should have bought an bottoming tap too so I could finish it off and tap it all the way but eh. Its deep enough for the bolt I will be using.

http://i1206.photobucket.com/albums/...c/DSC_0100.jpg

Hardware store didn't have any hex head m12 bolts in.

http://i1206.photobucket.com/albums/...c/DSC_0101.jpg

http://i1206.photobucket.com/albums/...c/DSC_0102.jpg

Heli coil is old technology ACE hardware junk, go with a time cert, its a full bushing, can be installed in a blind hole and is stronger than anything else including the original threads. Put it in and never worry about it. After all, it only a P/S pump with belt tension on it 24/7

Time sert sounded nice, but it's already repaired by going with m12 tap and bolt.

Also you guys are forgetting this was on the BACK side of the heads not the front where ACC brackets bolt on. I repaired this simply because it's a spot I like to attach my chain or load leveler when moving the engine around or playing it in the car.

Other wise I wouldn't have given two shits and left the threads damaged.