Upper alternator bracket bolt
Thread Starter
Safety Car
Joined: Dec 2006
Posts: 4,290
Likes: 6
From: St Marys GA
Upper alternator bracket bolt
Can anyone tell me the thread type on the bolt that connects the upper/rear support bracket to the alternator? It's not the same bolt as the compressor, and nothing I've stuck in there seems to work, which is a bad approach in the first place. It somehow fell out after I installed my headers, ever though my 'assistant' swears he reinstalled the bolt... 
Thanks in advance!
EDIT: Here is a picture of the bolt I am talking about. It's the missing one...
Thanks in advance!
EDIT: Here is a picture of the bolt I am talking about. It's the missing one...
Last edited by StealthLT4; Jun 3, 2012 at 05:43 PM.
Thread Starter
Safety Car
Joined: Dec 2006
Posts: 4,290
Likes: 6
From: St Marys GA
It's much bigger than 5/16. Here's all the stuff I've tried; the only thing that will thread in there is the M10x1.5, but it doesn't feel like it's fully engaged. Like that's not the real thread, but it's catching.
7/16-14
7/16-20
1/2-13
1/2-20
M10x1.5
M12x1.75
I'm stumped. There aren't any other thread sizes at the hardware store close to that diameter. Right now I have an M10 stuck in there, but if I try to really torque down on it I can feel it stripping the threads, so I really don't think that's the right size.
7/16-14
7/16-20
1/2-13
1/2-20
M10x1.5
M12x1.75
I'm stumped. There aren't any other thread sizes at the hardware store close to that diameter. Right now I have an M10 stuck in there, but if I try to really torque down on it I can feel it stripping the threads, so I really don't think that's the right size.
Le Mans Master
Joined: Feb 2000
Posts: 9,715
Likes: 27
From: Kempner Texas
If you're referring to the support brace, one end to the exhaust manifold and the other end to the alternator, mine is metric and stamped on the head of the bolt is "M 9.8"
Hope this helps.
Jake
West Point ROCKS!
Hope this helps.
Jake
West Point ROCKS!
Thread Starter
Safety Car
Joined: Dec 2006
Posts: 4,290
Likes: 6
From: St Marys GA
Update 6/3/12: I added a picture, since I am doing a bunch of work on the car and figure I'll give this thing another go. Anyone have one they can measure, or know the thread? "M 9.8" means it's metric, but the 9.8 is just the grade (kind of like Grade 8 for SAE).
Team Owner
Joined: Sep 2003
Posts: 25,377
Likes: 2,735
Someone may have actually attempted a 3/8 bolt and ruined the threads or maybe they're actually destroyed.
If you want to find out I guess the easiest way would be have a parts store pull an alternator off the shelf!!!
I believe what is confusing is the one that is hidden behind the ASR in your snapshot on the end of that same bracket is actually 3/8 X 16
Last edited by WVZR-1; Jun 3, 2012 at 08:54 PM.
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Thread Starter
Safety Car
Joined: Dec 2006
Posts: 4,290
Likes: 6
From: St Marys GA
Thanks for the replies. I remember that a 10x1.5 did not fit properly, so your comment about a 3/8" being tried may be true. I'm probably going to try tapping it back to 10x1.5, but if that doesn't work its Helicoil/Time-Sert time!
