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Discussion Starter #1


When I was cleaning up and painting this engine, I missed the fact that the front alternator bracket mounting hole has a 3/8-16 bolt broken off in it about 3/16” below flush. What to do?
1) Drill and tap the old bolt for a 5/16 bolt. Use a left hand drill bit in the event it is willing to catch and back out.
2) Remove it with an easy out, hoping not to break off break off the easy out in the hole.
3) Being so close to the new pan gasket, heat-related techniques are undesirable.
4) Buy a bracket that mounts to the front of the block. Davispeedequip sells them on eBay, part number 10022 or 10022AA. This looks like a good plan B if others fail. Does anyone have experience with these brackets?
 

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Use a left handed bit as you said Mark, use a center punch to put a dimple in the middle if at all possible...it may back out with the drill bit if not the left hand easy out will bring it out...
 

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Discussion Starter #4
The fact that I can buy a bracket to mount the alternator to the front of the block makes me a fair bit bolder with the easy-out.

I am glad that I spotted the issue before I installed the engine; it is far easier to access the bottom edge of the block while it is on an engine stand.
 

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Discussion Starter #6
Easy-Out Not Effective

I drilled it out with a left-hand drill and tapped in the easy-out. I applied torque with a T-bar and it just tore the hole open. I think I will next get a 5/16-18 bottoming tap and see if I can get some usable threads cut in that hole. If the hole is too big from the easy-out, I will try again with the 3/8-16 bottoming tap.
 

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unless your way off center just drill hole with 1/4 and tap with 5/16

or drill with 5/16 then tap with 3/8 the engine being out makes it so much easier
 

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unless your way off center just drill hole with 1/4 and tap with 5/16

or drill with 5/16 then tap with 3/8 the engine being out makes it so much easier
That would be my choice..!
 

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Discussion Starter #9
Easy-Out Fail

If the broken bolt had been flush or proud of the block, I would have welded a nut onto the old stud. However, it was about 1/4” less than flush.

I drilled it for the easy-out, tapped it in, and the easy out ripped out the center of the stud. I went to plan B and ordered the steel mount for bolting it to the front of the block with two 7/16-14 holes. I will need to chase the threads; they have been empty for many years. What were those holes in the block (front of the block and towards the drivers sided, just above the pan) intended for?
 

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I went to plan B and ordered the steel mount for bolting it to the front of the block with two 7/16-14 holes. I will need to chase the threads; they have been empty for many years. What were those holes in the block (front of the block and towards the drivers sided, just above the pan) intended for?
Originally for accessory brackets..
 
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