my exhaust manifold is cracking. Just buy another?

[LaGrasta]

I noticed two growing cracks near the bolts on my manifold. Do I just order another with a matching gasket or is there an upgrade I should know about? I'm not going with headers. Order the gasket from? Torque to the factory manual?

Basically, is this as straight forward as it sounds or is there any secrets?

 

[wallaka]

It's pretty straightforward. Do you have the brace on the downpipe? That will make the manifolds last longer and many people don't have them.

 

[Anonymous]

why no headers? just out of curiosity

 

[LaGrasta]

I don't even know what brace you're speaking of. Any pics?

I had a great set of Hooker Headers and ended up selling them because as this is a daily driver, I kept being told it would cause more problems than they're worth. Heat was the main cause of the trouble that would follow if I installed them. I also have a/c installed. andd clearance is an issue on the exhaust side.

 

[69Falcon]

I don't plan on running headers either, because that would require re-doing the A/C system I put in. And believe me, with a black vinyl interior, I'll take the A/C over a few hp any day!

It'll be interesting to see what impact the stock exhaust manifolds would have on Mike's new head. I wonder if performance would really suffer?

 

[powerband]

A Cautionary note...

Replacing a bad manifold is straightforward. Getting the old bolts out without removing the head - now that can be a challenge. I've suffered with a leaky manifold for a while on the '63 because the manifold bolts will not come out without a few snapping off. The last engine D3xx 250 - I dis-assembled and had the head "built" needed most of the exhaust bolt holes drilled and re-tapped. Not a big deal if the head is out.

Powerband 8)

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[wallaka]

I had some problems when I first got the Comet. Luckily the exhaust bolts didn't snap--they rounded off instead. :roll: I happened to be on the Snap-On truck that week and saw extractors that looked like sockets with reverse spiral grooves on the inside that bites into the rounded head of bolts. Bought the right size and went to town with the impact from underneath with a looong extension and "wiggler" adapter. They now have those extractors at Sears and are quite handy.

Anyhoo, I don't have a picture but there is a brace that bolts up to the block under the manifold area near the oilpan line. It holds the exhaust pipe to the engine so it won't flex. That's what causes the (notorious) breakage of the exhaust manifolds according to my Dad. He and all his friends had Falcons when they were still in production and everybody that didn't have the brace had mucho problems with manifold breakage.

I made a sketch of the brace. It's just stamped steel and an exhaust clamp affixes it to the downpipe.

 

[LaGrasta]

The brace looks to be a good idea. I'll fab something up and attach it upon my reinstall.

powerband, do you mean "nuts" or "bolts"? I just back the nuts off, correct?

 

[Mercury Mike]

Hey grasta, I got a spare manifold. I don't think it's cracked. I've got the brace, too.

 

[LaGrasta]

To install a used one means I have to plane the flange side? Anything else to consider since it's used? I only want to do this once.

If this is a no brainer with the used one, I'll take it.

 

[fordconvert]

I bought a 'reproduction' manifold from mustangs unlimited. I suspect that it is the same one they all sell since the price seems to be the same everywhere ($120ish) except one I have seen on someones ebay store for like $40. I just bolted it on with a set of bolts with strange cup washers I bought from the same place with the FelPro gasket that is foil looking on one side and fiber on the other. 400 miles so far and no leaks or cracks. My engine builder friend told me to not bother surfacing it first because many of the cheap castings (like rotors also) tend to warp after you use them because they are not treated properly in the factory so you have to pull them again anyway so just try it and you may get lucky.

I like the brace idea since there is no support till you get to the muffler behind the axle on the mustang. I was going to add some hangars to help that. Does anyone sell the braces?

 

[Mercury Mike]

I actually have a spare exhaust manifold gasket in the trunk. I got a set of gaskets, and I don't need that particular one, along with a couple others (thermostat housing, water pump...) Let me know what you need. mwilhelmus@gmail.com

 

[LaGrasta]

email sent 65stang200.

fordconvert, I'm only speaking of surfacing a used OEM exhaust manifold after magnifluxing it to make sure it's not cracked. A reproduction piece would be a bolt-on as it's never been installed. I found repros for $99. That may really be the way to go since it's a slam dunk.

 

[JackFish]

Does anyone sell the braces?

I'd like one also, any leads on these? If anyone has one to part with, PM me.

 

[LaGrasta]

I'm thinking a regular exhaust hanger would work as there are many different styles. Just choose a rigid type and add a U-bolt clamp.

 

[wallaka]

I'm sure that would work fine.

 

[LaGrasta]

I looked up my numbers this morning on the manifold, C3DE-9430-A. I think I'll get 65Stang200 old 200 manifold. I'll clean the surface myself, add a new gasket and donut as well as the additional brace that I didn't even know existed and see how it goes.

By the way, aside from e-bay, Virginia Mustang has the best prices on manifolds, $99. www.virginiamustang.com This company contiunes to have the best prices on most everything I check on. I order many "Mustang items" for my Falcon.

 

[The Plankster Prankster]

my advice would be to check the surface on teh head that it mates to. it that surface is warped, thatll cause it to break.

powerband, do you mean "nuts" or "bolts"? I just back the nuts off, correct?

he assumed you had bolts, but apparently you have studs. yeah, just take the nuts off em.

when replacing parts, a fool will blindly hang parts, but a wise man will determine how & why it broke, fix the cause of the problem, and then hang a new part.
sounds like the missing brace is your cause, so fab one up and good luck!
--josh

 

[LaGrasta]

Thanks Josh. I really do think the brace will make the difference. It would explain the location of the cracks. I'll give it a shot.

 

[LaGrasta]

http://www.virginiaclassicmustang.com/c ... temid=EH68


Here's the exhuast clamp, brand new for $9. Just add the u-bolt or weld it on directly.