Exhaust Manifold StudsW

[woodjunky]

I have the Exhaust Manifold off. Five of the Thirteen broke off, two in the block. This is after heat and few weeks of PB Blaster.

My question is the 3/8 stud thread that goes into the block. Is it the USS Course, or the Sae Fine, like the nut side ?

 

What are the actual lengths of the Long Studs, and the Short ones ?

 

Also does a Auto Parts Store such as O'Reilly's carry these. I will need the two long studs, and three short one's.

[Don Coatney]

Studs are all course (USS) on one end and fine (SAE) on the other end. I don't recall the length but I used two grade 8 bolts as pictured below.

 

 

[TodFitch]

Threads into the block are course thread. If your local auto supply does not have suitable studs, try a good hardware store. If you can't find them locally and don't want to wait for a shipment from a mail order place you can make studs from long bolts with not much more than a hacksaw and an appropriate die. Manifold studs are not under a lot of force, just heat, so strength is not a big issue.

[woodjunky]

Thank you Don and Tod. Good and useful information.

[NiftyFifty]

I did the exact same as Don, works just fine, and easier to find

[Don Coatney]

Threads into the block are course thread. If your local auto supply does not have suitable studs, try a good hardware store. If you can't find them locally and don't want to wait for a shipment from a mail order place you can make studs from long bolts with not much more than a hacksaw and an appropriate die. Manifold studs are not under a lot of force, just heat, so strength is not a big issue.

I would not recommend that because studs have a certain number of threads and can only go so deep into the block and are designed to bottom out the threads. All thread will go in until it hits a dead end. Granted this is not a high or precise torque application. I measured the bolts I used so the block penetration was the same as studs.

 

If you cannot locate studs at a local hardware store I have had excellent results using McMaster Carr as a hardware supplier. They normally ship the same day and your stuff arrives quickly.

 

Don't forget to use thread sealant on the manifold fasteners that go into the block as many will hit the water jacket.

[TodFitch]

I would not recommend that because studs have a certain number of threads and can only go so deep into the block and are designed to bottom out the threads. All thread will go in until it hits a dead end. Granted this is not a high or precise torque application. I measured the bolts I used so the block penetration was the same as studs.

 

If you cannot locate studs at a local hardware store I have had excellent results using McMaster Carr as a hardware supplier. They normally ship the same day and your stuff arrives quickly.

 

Don't forget to use thread sealant on the manifold fasteners that go into the block as many will hit the water jacket.

 

 

I did not suggest using all thread. . . I suggested using a bolt for the stock to start with. Threaded section picked appropriately. I don't see how you could put a good fine thread end on a course threaded piece all-thread anyway.

 

I didn't even use all-thread when making the shock link rods for the lever action shocks on my Plymouth: 3/8" steel rods, cut to length and then each end threaded as needed.

[Don Coatney]

Now I understand. I thought your suggestion was to use a long bolt with course threads, cut the threaded portion to length and use course threads both ends the same as all thread. I did not pick up on using a die to cut new threads.  I thought the die was to chase the threads from the hack saw cut.