The #3 bolt looks fine but when I was torquing it, it seemed like something striped all the other bolts are to the final torque but number 3 it just keeps spinning I imagine this isn't a good thing....

What do I do??

Thanks

Remove the head and install a heli-coil. You'll need another head gasket if it's been partially torqued.

 

GD

Ughh where do I get one of those?...

aluminum engines are very unforgiving if you over torque or put the bolt in cock-eyed. Sounds like you stripped the threads. Get a sharp drill bit, re-tap the threads and/or heli-coil it.

Any auto-parts store will carry some form of heli-coil. That is only one brand of thread repair. There's probably half a dozen at least. Just ask for a thread repair kit in the size of your bolt. Probably 10mm or 12mm - can't remember off the top of my head. This is common with aluminium and you should inspect the threads carefully and repair any that are damaged prior to attempting to install the head a second time.

 

GD

take a head bolt with you to the store to verify the thread size.

If I remember correctly, the head bolt threads are M11x1.25.

Very non-standard.

No parts store will have that size helicoil in stock.

Check the internet...

 

Or drill the hole bigger, get an M12 helicoil, and a new bolt/stud.

Somebody has to ask the dumb questions, so I guess it is my turn this week...

 

Do you have the proper length bolt in that position? There are 2 different lengths of headbolts; could you have possibly used a short bolt in a long bolt's position?

 

Otherwise, yes the headbolts are a non-standard pitch, 11mm x 1.25. Not impossible, but good luck. A little bit easier to find in the PNW corner of the USA.

PM me if you can't find the helicoil locally. I'm pretty sure I've still got a headbolt kit in the garage from when I had to do mine.

Well my shop teacher said to drill the hole bigger and tap it with a different size the head bolt that came out of the car matched up perfectly with a 7/16th-20 size and thread So Im gonna drill the hole bigger to fit a 1/2-20 bolt. My teacher has said this has worked for him in the past I just have to be very careful. :-\

I hope it works out.

Should I be doing this?

Thanks for all the hell too It was just what I was looking for.

Oh and about the bolt being the wrong size I'm pretty sure that I used the right size I measured them all out.

Should I be doing this?

 

No - it likely won't fit through the head. Mixing standard and metric like that is amaturish and it will be difficult to match up a new non-metric bolt with a similar grade.

 

If you must, install a 10mm x 1.0 heli-coil and source a stud for that location. 10mmx1.0 is much more common and you should be able to heli-coil down 1mm without any drilling - just tap it and install the heli-coil.

 

Otherwise do it right and get the proper heli-coil - while you are at it do the rest of them as well. Or at least chase the threads with a proper tap.

 

GD

Right now I don't have that kind of money to do that and the 1/2 tap fits into the head hole and I think it will work. and nobody has the right size helicoil

Unfortunately if you use a larger diameter *bolt* you are going to affect the torque value required to put the same amount of clamp force on the head gasket. The larger diameter bolt will not stretch the same even if you get the exact same grade (there aren't exact equivelents of grade between standard and metric either so that's another concern). You had better discuss such things with an engineer or a very good machinist before doing it. There are formuli to determine such things, but I am not versed in them and would have to research it.

 

Having an unequal clamping force for a single bolt is a really bad idea - will almost certainly warp the head and probably cause a premature gasket failure.

 

GD

... A little bit easier to find in the PNW corner of the USA.

 

Excuse me, Could I Ask the Meaning of "PNW Corner"?

 

 

...Or drill the hole bigger, get an M12 helicoil, and a new bolt/stud.

 

I Have a Thread with Pictures about the Procedure of How to Re-Thread in Aluminium... I`ve done it in a Different Area of the Engine`s Block but I Hope that Might Help you.

To Reach it, Click on my Avatar, in my "Public Profile" you`ll Find a List of my Writeups, then there is it.

Kind Regards.

Good Luck!

Excuse me, Could I Ask the Meaning of "PNW Corner"?

 

He's is refering to the "Pacific North West" corner of the USA. So basically Oregon, Washington, Idaho, etc. Pacific refers to the pacific ocean and North-West should be obvious yes?

 

GD

Thank you for your Kind Answer! Now I Understand.

Thank you for your Kind Answer! Now I Understand.

My apologies for using a regional slang phrase. Subarus are extremely popular and common in this region of the USA, and cars, parts and tools that might be difficult to obtain elsewhere are easier to find here.

 

It seems to be that I saw 11mm x 1.25 Helicoils at our local auto parts store that was supplied by the "Parts+" distributors. (Parts store has since gone with NAPA parts.)

Any decent tool supplier should have them as well. Fastenal could probably get them in 1 business day. There are many others.

 

GD

Any decent tool supplier should have them as well. Fastenal could probably get them in 1 business day. There are many others.

 

GD

+1 on GD's recommendations: Fix it right, or expect to be redoing the work ( probably needing a replacement engine) really soon.

Well I might as well get the helicoil if thats the easiest way to do it, I dont want to warp the head and I no nothing about converting torque according to the dia. of the bolt.

I'm going to go to the fasnal right down the street and see if they have any helicoil.

Thanks for all the suggestions too!

I think fastenal sells the "Recoil" branded version. Same thing though. But I could be wrong about the brand - we buy from so many suppliers I get confused.

 

GD

Well I called ace hardware and they said they have a 12mm 1.25 but I need a 11mm 1.25 right?

And the bolt fit right into a 7/16 20 could I use that too??

Edited May 16, 200916 yr by tysree

What does this mean? M12 x 1.75 x 9

Should I use this size helicoil and get a new bolt?

What does this mean? M12 x 1.75 x 9

Should I use this size helicoil and get a new bolt?

 

You don't want a new bolt - it's not going to be the correct grade and the aformentioned problems with torque are no different with a larger metric bolt than they were with a larger standard bolt.

 

You need to find an M11 x 1.25.... the last number is the depth and that's not important for your puposes.

 

GD

I have a Coil Sert repair kit for M11x1.25 part number is IK405-11.

 

I bought it online somewhere a few years back.