[JCP]

After getitng this jeepster and fixing a number of things. I was checking the oil and noticed that the exhaust manifold is cracked on the drivers side (225 v6) It looks like the crack goes most of the way around. can this be welded? Where would one look for a replacement?. If I tried to weld it should I weld the part I can get to befor taking it of so it soes not move and I won't change the fit?

jcp

 

[Guest]

I have welded cast iron with both TIG and Stick with mixed results. It requires special filler rod, which is high in nickel content, and preheating the part. Most of my successes (one of which was an exhaust manifold) have been with high quality American cast iron. My failure was also a manifold, this one off of a Ford Tempo. I believe that this one was made of "chinese mud cast" as right before the metal got hot enough to flow it would flare up like a sparkler.

Anyway all of that to say, if you can I would try and find a replacement manifold. If not find a reputable welding shop that is experienced at cast and have them do it.
Also, you may have problems with fit after it is welded. The heating and cooling of the metal will make it a beast to install and make seal.

Just my opinion for what it is worth.

 

[HOGHEAD]

We used a Flat plate of 3/4 steel ,,drilled & Tapped to fit many diferent manifolds ,,, bolted it down then pre-heated till the sout off a rich Oxy Acl torch would burn off,,, it burns at 300 degrees ,, (if memory serves me right) then used the highest grade cast rod made at the time ,, Some worked great some cracked as we were putting them back on ,, You need to let it cool slow , By wrapping in a fire blanket , to keep the air off it ,,,,

Real pain Id look for a used one ,,,,

 

[clffhnger]

The previous guys are right. Try to find another one. But just for fun you can try and weld it.
I havn't had as much experience as the two previous replys, but I've had no leaks in my F250's exaust manifold after I welded it up in two places over 5 years ago. I used my little 110v lincoln wire feed welder with no special wire.

 

[Danger_Dave]

If you do replace it, get a rear dump one from an early 70's Buick 231 V6. I found one online for about $30.

Now, another alternative - and I'm not endorsing this - is POR's Fire Seal 2000.

http://www.prp-porstore.com/merchant.mvc?Screen=PROD&Product_Code=FS&Category_Code=Fillers

I have no idea how well this stuff works, but it's cheap enough to try, even if you wind up replacing the manifold anyways. And if you do try it, please let me know if it works...

 

[1078]

Fpr $10 bucks, it would have to be worth a shot

 

[JCP]

Dave where did you get the used one?

JCP

 

[Danger_Dave]

I think I found it here:

http://www.autopartsearch.com/index.cfm

I think it was off of a '74 Buick Century with a 3.8L V6 (231). Be sure you get the year right - there's a difference in the ports where the exhaust manifold bolts to the engine - the early ones are dog-legged, the later ones are rectangular. If you'll do a search on exhaust manifolds, there should be some more reliable information than I can give (and a picture or drawing or two).

If you want to check on model years, go to partsamerica.com, search under gaskets for the exhaust manifold gaskets, and look up the earliest Buick Regal with a 3.8L engine.

 

[dan01ster]

Jeff, if you're buying one from somebody, make sure you get the proper unit for your application. Some sellers might not know that there is a 'Rear' dump and a ' Front' dump. Only the convertible (Ross steering) used the front dump. Some folks would take for granted that all left sides were the same. Not so.

 

[010]

$ 30 wow thats a lot. at the local u pull em there are $5 each

 

[SteveInColorado]

If you're a pretty good welder, you can use 7018 wire or rod if you preheat it pretty well. I've never personally met anybody that can gaurantee a cast weld to hold, and the stuff I've done this way probably lasts 60% of the time (never had a weld on anything else break ever). Exhaust manifolds are bad about warping and shrinking all on their own, so you definitely need to bolt it down. It's probably OK to take it off then weld it, since if anything, it's shrunk.

Steve.

 

[JCP]

Dave could you double check the year and make of buik for the exhaust. I'm being quoted 60 bucks and want to make sure and get the right one!

Thank you

jcp

 

[3227]

i searched and in aug of 03, danger dave posted the correct drivers side exh manifold. look for it under "correct drivers side exhause manifold". it is a 76 buick century 231 manifold. interesting threads on it though. good luck, joe.

 

[Danger_Dave]

Try here: http://www.capitalautoparts.com/

Search for a '76 Buick Century with a 3.8L - they had one listed for $25.

 

[RRich]

If you need to get it welded, I've had good luck by calling a big truck or earth mover shop - like CAT or CASE, John Deer etc. They use lots of cast stuff that's always breaking - they usually know someone that specializes in it - and that's very good at it.

The place I used to use had a big furnace to preheat everything for quite awhile - the entire part, then they'd weld it, then let it cool down very slowly. Pricey, but well worth it when you are stuck.

Best if you have a spare head you can bolt it to to keep it straight.