Manifold Gasket and STud install Question

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FrobiOne

FrobiOne

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Had an Exhaust leak so i decided to change my gasket. Unfortunately the exhaust manifold is cracked but i got all the studs out with out breaking any myself.

I was curious what sealer i should use on the studs?

Also the front and rear top holes to mount exhaust manifold were broken off do they require the same stud or do i just use bolts?

Anyone got a lead on a cheap header or Headers?
 
Are there supposed to be 10 of the triangular washers that hold the intake exhaust manifold on?
 
NO, some are triangles and some are round. Read the reference on www.slantsix org; it has all you want to know there. BTW, I like to use thin blue RTV on the intake ports and red RTV on the exhaust ports. The broken off ears are a problem; time to find another manifold. These probably broke off exactly BECAUSE someone did not use the right brass beveled washers and studs/inverted nuts on these 2 spots and just bolts instead; it would be wise to not repeat their mistake! There is a thread on here from early in the year on what parts to get and where; search for the poster 'trudysduster' in this subforum.
 
nm9stheham said:
NO, some are triangles and some are round. Read the reference on www.slantsix org; it has all you want to know there. BTW, I like to use thin blue RTV on the intake ports and red RTV on the exhaust ports. The broken off ears are a problem; time to find another manifold. These probably broke off exactly BECAUSE someone did not use the right brass beveled washers and studs/inverted nuts on these 2 spots and just bolts instead; it would be wise to not repeat their mistake! There is a thread on here from early in the year on what parts to get and where; search for the poster 'trudysduster' in this subforum.
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I pulled 9 off and one round one from top center. Do i have them all? Where do i get this brass beveled washer?
 
If you have 9, you should have 10. Apparently some early ones used 8 triangles and used round on the 2 lower center positions. The top center is a steel conical washer. The brass washers are about 1/4 inch thick on both ends they dont need to be conical. The special nut that goes into them is tapered and will seat in regardless. I would need to check the outer dimension of the brass, those and the nuts could probably be found at mcmaster.com. I used brass nuts on all other positions except the ends. Are you getting another manifold?. If you go with silver-seal, you will get most of the special hardware and they sell the studs.
 
zkx14 said:
If you have 9, you should have 10. Apparently some early ones used 8 triangles and used round on the 2 lower center positions. The top center is a steel conical washer. The brass washers are about 1/4 inch thick on both ends they dont need to be conical. The special nut that goes into them is tapered and will seat in regardless. I would need to check the outer dimension of the brass, those and the nuts could probably be found at mcmaster.com. I used brass nuts on all other positions except the ends. Are you getting another manifold?. If you go with silver-seal, you will get most of the special hardware and they sell the studs.
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I scored an original Manifold off ebay. Just need to finalize the hardware situation. Having trouble locating the end hardware. Both ends on mine were broke off. Anyone have a single triangular washer laying around?
 
This end hardware seems to be particular. Does it really matter? If i follow the 10lbs torque specs will not be be OK with a washer and/or lock washer? brass, stainless or zinc coated nut gonna make any difference?
 
FrobiOne said:
I pulled 9 off and one round one from top center. Do i have them all? Where do i get this brass beveled washer?
Click to expand...


Look carefully on the bottom of the block behind the starter, maybe fish around with a magnet...

I found one or two of mine that fell down there during manifold removal....

Just go up and down the bottom edge of the block just above the oil pan and look for any that may have fallen...
 
FrobiOne said:
This end hardware seems to be particular. Does it really matter? If i follow the 10lbs torque specs will not be be OK with a washer and/or lock washer? brass, stainless or zinc coated nut gonna make any difference?
Click to expand...

Yes, they can all affect the outcome and torque....

I would try to stick with what it came with from the factory if possible...

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The important thing to remember is that this big, long exhaust manifold is designed to "slide" across the gasket surface and move around as it heats & cools. A stamped steel gasket is the best for allowing movement but is also the hardest to seal. The thick material gaskets are the opposite, easier to seal but they don't allow much manifold movement, which can lead to a cracked manifold. The manifold hardware is an important part of the installation. The special washers allow the manifold some movement while holding it down for sealing. The correct hardware must be used in the proper locations. The two acorn nuts go on the two top, outer end studs, with the coned shaped part of the nut fitting into the dished, conical part of the round brass washers. The center three studs get cup-shaped round cast iron washers, cupped faces towards the head. Everything else gets triangular butterfly washers.

Note that "later" SL6 engines came with only one round conical washer in the top center position. All the other were triangular type. This combination is also acceptable but installation of the lower, inner triangle washers can be a challenge, especially the one under the choke stove mounting pocket. A little grinding of the parting line in this location really helps to get socket access to that nut. Use a 1/4" socket set for easiest access. All the tab surfaces where the washers contact the manifold must be smooth and allow clearance on all sides. You may have to grind the sharp corners off the edges of the tab cutouts to ensure this. I use some anti-seize compound on the resurfaced flats to help the manifold "float" under the washers.


From slantsix.org

See page here for more detailed info:

http://www.slantsix.org/articles/manifold-install/types-mounting.htm
 
FrobiOne said:
This end hardware seems to be particular. Does it really matter? If i follow the 10lbs torque specs will not be be OK with a washer and/or lock washer? brass, stainless or zinc coated nut gonna make any difference?
Click to expand...

The end nuts are a type of locknut. Not sure what would happen if you used something different. These manifolds are tricky enough to get sealed and not broken. I was not brave enough to experiment. I did use a stainless/graphite Aussie gasket to improve the seal.
i do have some extra hardware, but i know i don't have the end nuts. I will check tonight what i have and if i can find the part number for the nut. As i said i think it was a mcmaster link...
 
Here's many different options that you can go with for many applications that will work on the slant...


This page has many singles and some complete packages:

http://www.manciniracing.com/oemexmastnu.html


I believe that these are the same round washers as the slant:

http://www.manciniracing.com/maraexmacowa.html


I would go with those style washers, and then you can just go to a hardware/home improvement/fastenal store and buy a box of 5/16" x 24 nuts (Fine thread - not coarse for the studs).
 
The triangles are shaped so the manifolds can slide, especially the exhaust, if its a sunday night and you need to get to work monday morning, you can take a round washer and grind it so there is 1/8 clearance where the washer fits between the manifolds. You need this clearance because the manifolds actually expand when heated and slide. If they are hitting, they are cracking....Oh and congrats on not breaking any of those studs. If you use brass nuts, they will not seize on the bolts in the future.
 
So I feel I'm still lost on what I need to attach both top corners of the exhaust manifold. McMaster has a lot of hardware and I'm not finding the right thread size for the nut I thought I should be using based on a bad picture on Slantsixdan.org. And as far as the washers in these position. I can use the same round conical washer that's used in the top center intake position?
 
zkx14 said:
http://www.forabodiesonly.com/mopar/showpost.php?p=1970680675&postcount=38

See link for mcmaster part #s. Bill (trudysduster) is quite particular about his builds, so I have no doubt these will do the job...
Click to expand...


I was able to track down the hardware at Fasenal using the McMaster part number. Only difference is brass washer thickness. .125 instead of McMasters .167 minimum. Easier for me to get local than online but some of the most expensive nuts and washers I've ever bought. Really appreciate all the help and info.
 
Fastenal part numbers
Brass washer # Z9096BR
lock nut 5/16 #37462
Brass 5/16-24 nut #75131
 
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