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View Full Version : Cross Threaded The LIMG

Nate's Alero
03-09-2009, 10:43 PM
man, if you have ever done an LIMG change, you know the side bolts on the LIM,

right above the thermostat housing, twards the firewall, well, i cross threaded it, i have heard tap it, new thread cutting bolt, etc. what do you all think?
kwhauck
03-09-2009, 11:37 PM
get a new LIM....
[ion] C2
03-09-2009, 11:47 PM
he says he crossthreaded the head not the manifold
kwhauck
03-09-2009, 11:55 PM
get a new head then......whatever, parts are cheap enough....
jayson_waltz
03-10-2009, 12:33 AM
just tap it a size bigger and use a dif bolt. problem solved.
WhiteV6
03-10-2009, 01:51 AM
If you only screwed up a couple threads, just retap it. If its bad enough, just drill and helicoil it. I have stripped test heads on the flowbench quite a few times and just retap.

You will probably need a new bolt. I haven't had any with good threads after that.
Beholder88
03-10-2009, 07:38 AM
I would just re-tap the head. You don't need an excessive amount of torque on that bolt so it's not like it will be under that much stress. I would just worry about the heat cycles. Keep an eye on it afterwards and maybe give it an extra half turn after a week or so.
Ryan from Ohio
03-10-2009, 08:18 AM
Its not the "head" its the thread.

I would first get a bottoming tap and run it through the hole. If you just cross threaded it a little (1-3 threads) you should be fine. If you cross threaded it to much you will need to get a Heli Coil. Just keep in mind its HIGHLY IMPORTANT when drilling out the old hole to hold the drill STRAIGHT AND STEADY. If you move the drill around while drilling it will blow the hole oversize. Then when you use the special tap, insert heli coil the heli coil wont be as tight.

And the matter of the fact is the heli coil is stronger than the initial threads :)

Just be aware you will get an Imperial set as you wont find metric in the stores usually...
Beholder88
03-10-2009, 08:45 AM
Its not the "head" its the thread.

It's the threads in the head...
Nate's Alero
03-10-2009, 10:31 AM
K

now what is a heli coil? and i went almost the entire bolt in btw... i know i rushed....
Beholder88
03-10-2009, 10:39 AM
A heli coil is almost what it sounds like. Its a little coil that you put into the hole that you drill out. it replaces the threads that are stipped. You can get them in various sizes at just about any parts store.
Nate's Alero
03-10-2009, 10:47 AM
A heli coil is almost what it sounds like. Its a little coil that you put into the hole that you drill out. it replaces the threads that are stipped. You can get them in various sizes at just about any parts store.

cool, i dont want to replace the threads, and i forget the tourque on the side bolts and on the top bolts of the LIMG and the tightning pattern help?
Gr1m
03-10-2009, 11:41 AM
damn dude i told you to take it slow, i had the exact same problem on that bolt and it took me about 35 minutes to get it to go in properly. precision and patience is key in engine work