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Help!My head bolts ripped the threads out of my block!


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I went to torq the bolts down and one just broke free:temper:

So, I figured I'd try and tighten the rest without torqing them down and another broke free. :madder:!

I should have known this would happen. The same thing happened when I changed the seals in my oil pump.:banghead:

 

 

Anyway, my question is, when I take my head back off to tap the hole and put a Heli-coil in, will It be OK to reuse my head gsket?

I mean, it probably got crushed little. Will this cause problems?

 

Anyone know what size Heli-coil to use?

 

Thanks

Sean

:boohoo: <me right now......:drunk: <---me in a few hours

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think of it this way. if your threads pulled out, it either means

 

you got your motor too hot before the rebuild!

 

or you are using a torque wrench that is broken

 

you are looking at a misprint in the chiltons and you are torquing too much.(happened to me on rod bolts)

 

junkyard motors are cheap:brow:

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Hmmm, I agree and disagree. I have had this happen in the past. What really sucks is when they do it after you have it all together and they start to pull on the final torque. Aluminum fatigues over time. Hot and cold over time stretches the threads.

 

You should be OK with the gaskets as long as final torque was not met. The helicoil is a 12mm but I can't remember the thread pitch. Take a bolt with you and they should be able to match it.

 

Good luck.

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Hmmm...That's funny.

 

My head bolts are 10mmx1.25 I think the Coil kit comes w/ 12mm tap & coils though.

It did overheat. That's why my head gasket blew.

But, I didn't even get to the first torq 22ft lbs. before they spun.

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Originally posted by archemitis

if two pulled out, arent they all going to pull out? thats alot of money in helicoils.

 

 

I was thinking the same thing.

A coil kit is $30. That's why I'm lookin for a short block f/s.

I haven't decided what to do yet.:cornfuzz:

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Hmmmmmmmmmm.... that is funny....

 

EA82 head bolts are M11 x 1.25. I would be surprised if yours was unique.

 

 

M10 and 11 are very close, and with the same pitch, I can see how someone could mistake them for one another. Here is an EA82 head bolt, from a random EA82 engine, with the "appropriate" die screwed onto it.

 

Dsc01924.jpg

 

You can clearly see M11 and HSS stamped into the die, although you can't see it in the pic, it also says 1.25.

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You didn't say what engine you have. The EA82 does use 11x1.25 head bolts.

 

Threads don't pull out unless the block has been really hot. If so, replace the block. (I have a machine shop and do only Subaru's - trust me on this.)

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Oh, great.:(

 

I already bolted the other head and cam houseing up. Everything on the one side was torqed down pefectly w/ no thread pulling.

So, I don't think it got that hot.

Maybe I'll just try the repair and if it don't work I'll swap the engine.

I guess I'll have to find someone to order me a m11x1.25 coil kit cause nobody has them in stock around here.

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M11 is fairly uncommon. I believe that someone else on the board recently had success using 7/16 coarse heli coils for their head bolts. You might try searching for that thread.

 

Is this the engine from the RX in your sig? If so, I'll bet that it is the turbo side head that you are having trouble with...

 

Good luck!

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I have a super cheap source for the M11x1.25 coils themselves, but not the whole kit. If you have an installing tool already and know the right drill size to use (and you're interested), I'll see if I can get some. They're from a surplus hardware store in town here, I noticed them when I was looking for some exhaust stud inserts.

 

Cost will probably be about USD$5 for 6 coil inserts, including shipping.

 

Just let me know.

Steve

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I don't know.

I'm gonna try to have someone near by order it.

I'm tempted to use the 10mm I bought.

It seems to fit perfectly.

When I screw the coil onto the bolt it goes on tight and easy with no play.

 

Do you guys think it would be OK to use it?

BTW...It's a Perma-coil kit not Heli-coil.

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Hi guys. I have a block that stripped out a hole- I borrowed Ezaps heli kit for 7/16 coarse, and bought some extra coils and 3' of threaded rod from NAPA for about $10.

 

I cut to size some lengths of rod (use nuts on it to mark your place to cut and clean up your threads) and was pleased.

 

I was not pleased after doing 1, resetting a fresh gasket (the first delaminated when seperating due to the 1st hole stripping-because I used some copper sealant- which I would not repeat doing-- $30 for another gasket) then I had 2 more fail.

 

The real problem I made for myself was in the process of drilling- I had no success in hold my 1/2" spade drill plumb and level while piloting out for the coils. This means I ended up with 3 studs facing like this /,\ and straight. I had to rasp out the holes in the darn head to get it to slide over! A little too shady tree to me.

 

I hope you fare better- if you have help, maybe have someone spotting you as you pilot out the block for you coils.

 

--PS I felt more secure using 2 coils per hole- if you go 7/16 they are pretty cheap I'd consider it

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Sven, Sven, Sven, what were you thinking? Threaded rod from Napa? What grade was it? A head bolt is at least grade 8. The holes should be drilled on at the very least a radial drill press and even better, a milling machine. The next problem that has to be addressed is the reason the threads stripped out to begin with. If it is metal fatigue, due to what ever reason, heat, stress, metal degrading, whatever, it doesn't mater what you do, it is going to fail again. It would be better to put the largest size coils you can in and use larger bolts. Yes, it will mean opening the head holes on size, but at least it will hold. Then the proper grade and length bolts. This needs to be done on the above mentioned equipment, or they will suffer from the same problem. I admire your try and fix it attitude, but there are some jobs that should be done by a machinist on machine tools. I have been doing it for more than 20 years, and aluminum is one of the least forgiving metals there is. It suffers from properties that steel doesn't. Mating the two together causes even more problems, but that is another story. Another option with aluminum is to heliarc and re-drill and tap the holes. New metal and re-alignment of the parent metal. It takes someone that really knows there stuff for that, or they over heat the part. Good luck and it seems like you learned from your experience.

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bbs53... If that makes you queezy I just won't tell you what I tried to pass as a "valve job" hehee

Mind you this is a motor out of a $150 car, not even a $150 motor. Nothing but the best as far as threaded rod- grade 3!!!

The goal was to get this car up and about for as little $$$ as possible- I really had no budget for the effort.

 

This hackjob is about to be retorqued, and It looks like I may keep the car as a second-- When she takes a poop I'll let you know.

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Yeah, but when you already torqed one head down and two threads rip out of the other, it's easier and cheaper to fix it.

I don't have an engine puller, if I did I would have bought another engine.

Remember, this is my everyday beater car. I'm just trying to get it on the road before the snow hits so, I won't have to risk crashing my RS.

 

Anyway, you guys said a 7/16 course coil kit would work. The only one I found was 7/16 14course but, the coil does match the threads.

Can you tell me what size 7/16 you used?

 

Thanks for your help!

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7/16 coarse was it, I just cut threaded rod to the same length as the head bolts as studs. If it wasn't 6pm on a sunday I would have gone to Tacoma Screw out here and gotten some hardened stock- I was able to get 1/2" in an equiv to grade 5 or so before- try calling a fastener shop if you've got one local. I wish you all the luck if you are trying to drill those out w/ the motor installed- room for a drill+bit+patience will be tough. If I had had another $150 I would have looked for another motor myself, but woulda still tried it out anyway

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