Exhaust Manifold Bolts and Gaskets - Sources?

[Coolvibes]

Took the exhaust manifold off, and would love to change the bolts; the threaded shafts are skinny, so would love to avoid breaking in the head in the future. Any sources for these bolts? Specs of the bolts?

Also, the OEM exhaust manifold gaskets seem to have spark plug heat shields attached. Are these still available, or should I reuse the OEMs? They seem to be in good condition, but would love to replace with new, of equal quality, if I can.

Car is a 1965 Dart, 273 V8. Thanks.

 

[diymirage]

Are you planning on drilling and tapping the bolt holes larger?

I guess I'm not sure how new bolts will not have the same "threaded shafts"

 

[toolmanmike]

Took the exhaust manifold off, and would love to change the bolts; the threaded shafts are skinny, so would love to avoid breaking in the head in the future. Any sources for these bolts? Specs of the bolts?

Also, the OEM exhaust manifold gaskets seem to have spark plug heat shields attached. Are these still available, or should I reuse the OEMs? They seem to be in good condition, but would love to replace with new, of equal quality, if I can.

Car is a 1965 Dart, 273 V8. Thanks.

HArdware kit: Exhaust Manifold Hardware Kit 1964-69 273/318, Exhaust Manifold Fasteners, 110-EMHK8062 Reproduction, NOS and Used Mopar Muscle Car Parts
I don't know if the gaskets are repopped. The 340 drivers side is I know. Not sure about the 273's though.

 

[cudamark]

Took the exhaust manifold off, and would love to change the bolts; the threaded shafts are skinny, so would love to avoid breaking in the head in the future. Any sources for these bolts? Specs of the bolts?

Also, the OEM exhaust manifold gaskets seem to have spark plug heat shields attached. Are these still available, or should I reuse the OEMs? They seem to be in good condition, but would love to replace with new, of equal quality, if I can.

Car is a 1965 Dart, 273 V8. Thanks.

If your gasket is still in good shape, you can reuse it. I would recommend a good quality sealer for the gasket surfaces though. As for the manifold hardware....the ends should have studs that go into a water jacket. Coarse threads into the head and fine threads for the nuts. If the studs are in decent shape, I'd leave them alone. If they have to be changed, make sure you use some good thread sealer on the cylinder head end. The bolts are nothing special. Bring a sample to your local hardware store and find some grade 8 replacements. There again, coarse threads into the head and use some anti-seize compound on those since they go into a blind hole. The conical washer may be a bit harder to find, but, there should be lots of used ones out there if yours are missing or junk.

 

[Coolvibes]

If your gasket is still in good shape, you can reuse it. I would recommend a good quality sealer for the gasket surfaces though. As for the manifold hardware....the ends should have studs that go into a water jacket. Coarse threads into the head and fine threads for the nuts. If the studs are in decent shape, I'd leave them alone. If they have to be changed, make sure you use some good thread sealer on the cylinder head end. The bolts are nothing special. Bring a sample to your local hardware store and find some grade 8 replacements. There again, coarse threads into the head and use some anti-seize compound on those since they go into a blind hole. The conical washer may be a bit harder to find, but, there should be lots of used ones out there if yours are missing or junk.

Good morning and thanks for the replies. I am not planning on drilling for larger bolts, just wanted to replace the used ones, with the hope that new ones will be less likely to break in the future. Yes, the end studs seem fine, so I will not touch those.

I will reuse the conical washers. Does it make a difference which way those are mounted; concave-in seems more logical?

What do you call a good quality sealant? Ones made specifically for exhaust? Any particular brand? I have never used sealant on exhaust gaskets before.

 

[cudamark]

The head of the bolts press against the convex side of the washers....concave side against the manifold. Look for a sealant with high temp specs. I believe Permatex, KW, Felpro, and probably a few others have them. I've used some Permatex Hi-temp RTV, KW Coppercoat, and Felpro Hi-Tac with good success depending on the application.

 

[Coolvibes]

The head of the bolts press against the convex side of the washers....concave side against the manifold. Look for a sealant with high temp specs. I believe Permatex, KW, Felpro, and probably a few others have them. I've used some Permatex Hi-temp RTV, KW Coppercoat, and Felpro Hi-Tac with good success depending on the application.

Ok, thanks much.