What bolt size and thread?
Thread Starter
Safety Car
Joined: Aug 2006
Posts: 4,347
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From: Apache Junction AZ
What bolt size and thread?
What is the thread size and depth for the two bolt holes shown on the front of the block near the freeze plug?
BJK
BJK
Last edited by 07MontRedcp; Jun 21, 2010 at 04:52 PM.
Safety Car
Joined: Jun 1999
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From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
Safety Car
Joined: Jun 1999
Posts: 3,570
Likes: 3
From: Austin, Singapore, Kuala Lumpur, Houston, Dallas, Hong Kong, Elgin, etc.. Texas
This should be an common bolt. It is metric marked 10.9 on the head and I believe its standard thread (not fine thread). I can hand thread it into the cylinder head with little resistance so it is the correct size bolt.
The bolt length in the photo is pretty short at about .625" so I don't think you will have a problem with.75" to 1.00" depending on the thickness of the bracket you are bolting on.
The bolt length in the photo is pretty short at about .625" so I don't think you will have a problem with.75" to 1.00" depending on the thickness of the bracket you are bolting on.
Thread Starter
Safety Car
Joined: Aug 2006
Posts: 4,347
Likes: 25
From: Apache Junction AZ
Well I went to Auto Zone to get a bolt and came away totally confused.
They had 3 different M10 bolts. All were 1.25 inches which is okay because I always use a washer and split lock, so that length would work.
The problem is one was 20mm, I guess that has something to due with the thread. The next one was 25mm and the last one was 40mm. I guess that number has to do with the courseness of the threads.
To make things worse, the picture that Mez provided shows an even courser thread that any of the above that Auto Zone had.
BJK
They had 3 different M10 bolts. All were 1.25 inches which is okay because I always use a washer and split lock, so that length would work.
The problem is one was 20mm, I guess that has something to due with the thread. The next one was 25mm and the last one was 40mm. I guess that number has to do with the courseness of the threads.
To make things worse, the picture that Mez provided shows an even courser thread that any of the above that Auto Zone had.BJK
Last edited by 07MontRedcp; Jun 24, 2010 at 08:20 PM.
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From: Pinellas Park Fl
St. Jude Donor '08-'09 & '12, '14
The 10.9 is the strength of the bolt. There are others, but, 5.8, 8.8 and 10.9 are the most common for automotive use. A 10.9 is similar to a grade 8 in an SAE bolt. They also identify them with lines like the SAE bolts.
Metrics are identified by size and thread pitch by length, M (metric) 8mm ( size) X 1.25 (pitch) X 30 mm (length) or 8 X1.25 X 25
That bolt hole in the head is a M10 X 1.50 and a 20mm length should fit
You should not use a flat washer and a lock washer, one or the other, but not both. If you want a wide washer with locking ability, use an internal or external star washer.
Metrics are identified by size and thread pitch by length, M (metric) 8mm ( size) X 1.25 (pitch) X 30 mm (length) or 8 X1.25 X 25
That bolt hole in the head is a M10 X 1.50 and a 20mm length should fit
You should not use a flat washer and a lock washer, one or the other, but not both. If you want a wide washer with locking ability, use an internal or external star washer.
Last edited by glenB; Jun 24, 2010 at 10:10 PM.
Thread Starter
Safety Car
Joined: Aug 2006
Posts: 4,347
Likes: 25
From: Apache Junction AZ
Cool, thanks.
The bolts I was looking at were stamped 8.8. When I got back home and checked the pictures that Mez provided I did cross my mind that the thread looked like a machine course but I was confused by the metric sizing.
BJK
The bolts I was looking at were stamped 8.8. When I got back home and checked the pictures that Mez provided I did cross my mind that the thread looked like a machine course but I was confused by the metric sizing.BJK
