Starter Bolt Question

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You guys have successfully talked another person with marginal mechanic skills off the ledge. PB Blaster this week and then the sockets recommended by Bill and the bolt came right off. New starter installed. Old one has a 1975 date code. Now for one more question. The new starter has a thicker mounting flange but on the top bolt I reused the stock one. It grabbed fine but a few threads longer would not hurt. On the bottom of course i had to use a new bolt due to the "incident" I had two candidates one of which was slightly longer and non threaded near the head which was fine as the flange isn't threaded. However. To me this bolt is aluminum? It was light grey and definitely not stainless steel like my other choice. I am wondering if it will be strong enough for the job. Also stainless seems maybe not a good idea in case it ever gets frozen in there again and I have to drill it out.

Am I setting up for an issue down the road? I'll be happy to buy new bolts. Just not sure which type is best here.

Thanks again guys. Very satisfying to hear the motor turn over.

Sent from my SM-G935V using Tapatalk

 
You guys have successfully talked another person with marginal mechanic skills off the ledge.  PB Blaster this week and then the sockets recommended by Bill and the bolt came right off.  New starter installed.  Old one has a 1975 date code.  Now for one more question. The new starter has a thicker mounting flange but on the top bolt I reused the stock one. It grabbed fine but a few threads longer would not hurt.  On the bottom of course i had to use a new bolt due to the "incident"  I had two candidates one of which was slightly longer and non threaded near the head which was fine as the flange isn't threaded.  However.  To me this bolt is aluminum?  It was light grey and definitely not stainless steel like my other choice.  I am wondering if it will be strong enough for the job.  Also stainless seems maybe not a good idea in case it ever gets frozen in there again and I have to drill it out.

Am I setting up for an issue down the road?    I'll be happy to buy new bolts.  Just not sure which type is best here.

Thanks again guys.  Very satisfying to hear the motor turn over.  

Sent from my SM-G935V using Tapatalk
I do doubt the bolt is aluminum. Check it with a magnet. Probably zinc plating. Stainless is not as hard as regular steel. Got to hardware and get a grade 8 bolt that is the strongest made. If you put anti seize on the threads the bolts will not freeze up. Bolts come in grades and are identified by marks on the head. A junk bold will have no marks, next grade has three, the next 6 and is what you want. There are stronger but no need for that here.

The OEM Ford starter bolts have an odd head on them usually shorter than other bolts.

One thing I forgot was rules for engagement, bolt engagement at least. For threads in cast iron you need two times the bolts diameter of thread engagement for steel you need 1 1/2 times the bolt diameter and I forget for aluminum but more than cast iron there. With that much engagement the bolt should break before you strip the threads in the mating parts.

http://www.gtsparkplugs.com/images/bolt-grade-markings-840x.jpg[/img]

 
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I would try a longer bolt on top. I think the hole goes all the way through the bell housing on top. If it does you can't go wrong. If it doesn't make sure the bolt is not 'too' long.

 
Thanks guys. Based on the marks it's a grade 5. I'll get better bolts and that's next weekend's job. Sadly the rear is leaking again so at some point I will have to address that gain. For now my new starter is turning well and I went for a ride. Lots of car people out today. Got stopped to talk several times.

Sent from my SM-G935V using Tapatalk

 
You guys have successfully talked another person with marginal mechanic skills off the ledge.  PB Blaster this week and then the sockets recommended by Bill and the bolt came right off.  New starter installed.  Old one has a 1975 date code.  Now for one more question. The new starter has a thicker mounting flange but on the top bolt I reused the stock one. It grabbed fine but a few threads longer would not hurt.  On the bottom of course i had to use a new bolt due to the "incident"  I had two candidates one of which was slightly longer and non threaded near the head which was fine as the flange isn't threaded.  However.  To me this bolt is aluminum?  It was light grey and definitely not stainless steel like my other choice.  I am wondering if it will be strong enough for the job.  Also stainless seems maybe not a good idea in case it ever gets frozen in there again and I have to drill it out.

Am I setting up for an issue down the road?    I'll be happy to buy new bolts.  Just not sure which type is best here.

Thanks again guys.  Very satisfying to hear the motor turn over.  

Sent from my SM-G935V using Tapatalk
I do doubt the bolt is aluminum. Check it with a magnet. Probably zinc plating. Stainless is not as hard as regular steel. Got to hardware and get a grade 8 bolt that is the strongest made. If you put anti seize on the threads the bolts will not freeze up. Bolts come in grades and are identified by marks on the head. A junk bold will have no marks, next grade has three, the next 6 and is what you want. There are stronger but no need for that here.

The OEM Ford starter bolts have an odd head on them usually shorter than other bolts.

One thing I forgot was rules for engagement, bolt engagement at least. For threads in cast iron you need two times the bolts diameter of thread engagement for steel you need 1 1/2 times the bolt diameter and I forget for aluminum but more than cast iron there. With that much engagement the bolt should break before you strip the threads in the mating parts.

http://www.gtsparkplugs.com/images/bolt-grade-markings-840x.jpg[/img]
Thanks again David. I don't know why I even thought that bolt could be aluminum. Galvanized or plated. Anyway the store had exactly the length i wanted. Even one a few threads longer which might be better here.
Sent from my SM-G935V using Tapatalk

 
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