Exhaust Manifold Guidance needed

[FiredomeVorhese]

I've been reading all the manifold stud related posts and still have some questions.

I cracked my exhaust manifold on my 53 Firedome.

It was a nightmare to get out, but I didn't snap any studs.

Found a replacement, gave it an electrolytic bath

Clean as a whistle

High temp engine paint

I have new manifold gaskets and exhaust flange gaskets.

I want to replace all the studs/hardware.

I read some of you had luck with Ace/Napa for the studs. Grade 8. Where online?

How do you install and torque the studs?

What's the torque spec? I can't find my manual from moving.

And do you use red loctite or anti-seize?

Any other advice?

http://vorhese.blogspot.com/

[greg g]

15 to 20 lbft on the 6's. Start at the light end then only tighten if you have audible ehaust leaks.

[Don Coatney]

When you talk about "stud" torque are you talking about how much torque should be applied to the stud when inserted into the engine block or the torque on the manifold hardware? I assume you are talking about the stud insertion.

Not sure on your Hemi engine but on the Mopar flathead engines many of the studs bottom out in the water jacket. So on my flathead engine I used pipe dope on all the studs. I screwed them in far enough so all were of the same length once screwed in and paid no attention to torque.

The studs are corse thread into the engine block and fine thread for the finish manifold torque value. Ace Hardware was my source.

[aero3113]

Don,the bolts in your pic,did you use stainless or grade 5?

[FiredomeVorhese]

I didn't even notice they were coarse and fine until you mentioned it.

[Don Coatney]

Don,the bolts in your pic,did you use stainless or grade 5?

What do the bolt head markings tell you?

[michael.warshaw]

what is that electric cleaning?

[Don Coatney]

what is that electric cleaning?

Good time for you to use the search function.

[FiredomeVorhese]

Elctrolytic rust removal

non metal tub

1 tablespoon baking soda for every gallon of water

put part in water solution

make sure battery charger is unplugged

hook negative up to part

put in sacrificial metal, make sure not to touch part, more metal the better

string together with alligator clips or other conductive means

hook positive to sacrificial metal

turn batter charger to 12V 6Amp

plug in

watch the bubbles

run for 12 hours or however long part needs

converts rust back to iron ore.

Part will have black scale

use green scotch brite to take off most of it

soap and water

bam

Edited November 16, 2010 by FiredomeVorhese

[aero3113]

What do the bolt head markings tell you?

Now that I looked at the head markings it looks like grade 8. Any reason grade 8 was used?

[Don Coatney]

Now that I looked at the head markings it looks like grade 8. Any reason grade 8 was used?

I used grade 8 on most all of my engine assembly. Just my preference.

[FiredomeVorhese]

One more question, what the heck is the purpose of the spring loaded butterfly valve that attaches to the bottom of the manifold? Mine was rusted shut and it seems a part that is doomed to fail. I can't figure out what use it would have, why would you want to restrict exhaust?

[Young Ed]

Thats the v8 version of a heat riser. Keeps the intake warm in cold weather driving.

[Don Coatney]

One more question, what the heck is the purpose of the spring loaded butterfly valve that attaches to the bottom of the manifold? Mine was rusted shut and it seems a part that is doomed to fail. I can't figure out what use it would have, why would you want to restrict exhaust?

Follow this link, scroll down, and read the "HEAT RISER ADVISOR". Then read everything else found on this page that supports this forum.

http://www40.addr.com/~merc583/mopar/framesets/techtipframeset.html

[FiredomeVorhese]

Well, I live in a moreless warm climate so mine is now a thru hole as I removed the completely rusted butterfly assembly. It was stuck at 1/2 or more closed. I'm guessing it should be fine. If I ever replaced the manifolds with headers, there wouldn't be an assembly.

[adam_knox]

Hey! Its the mysterious heat riser! My car's missing mine. Just make sure you patch the hole good before you install it. My car keeps turnign into a phantom Harley because all my attempts to keep the darn hole block end up failing! (course I'm trying to do a temp fix until I find myself one of those fancy risers! Glad to hear of your adventures!

[FiredomeVorhese]

Damn, I was doing good and was going to get it back together today. All cleaned up, put studs in, double nut, torqued to 15lbs... can't get the manifold on, it hits the frame. I got the studs from Napa, only ones they had in the size I needed, exact same length. The fine side is longer, which I thought would be good. Nope. Didn't realize how close it fits in there.

I need this exact stud:

3/8" X 1-9/16"L SS stud, Coarse side: 9/16"L, Fine side: 5/8"L.

Can anybody point me to a resto site that should have the right ones?

[Frank Elder]

Grainger, fastenal, McMaster-Carr all should have them...maybe even ace hardware and tractor supply:)

[Don Coatney]

Got my studs at Ace.

[TodFitch]

Damn, I was doing good and was going to get it back together today. All cleaned up, put studs in, double nut, torqued to 15lbs... can't get the manifold on, it hits the frame. I got the studs from Napa, only ones they had in the size I needed, exact same length. The fine side is longer, which I thought would be good. Nope. Didn't realize how close it fits in there.

I need this exact stud:

3/8" X 1-9/16"L SS stud, Coarse side: 9/16"L, Fine side: 5/8"L.

Can anybody point me to a resto site that should have the right ones?

Thread a nut, or better yet a die, on the side that is too long. Then cut off the extra and use the nut/die to clean up the damaged threads at the cut.

Of course the easiest thing would be to get one off the shelf at your local hardware store. But if they don't have them, not a big deal. Just make them. The manifold studs are not a highly stressed, high tech bit of alloy. Worse comes to worse, simply buy some steel rod, cut to length and then thread the ends as needed.

[FiredomeVorhese]

Ok I'll just modify them, See how that goes. Lost my window to work, try again in a week. Thanks.