: 94 fwb exhaust manifold looks broke



newside
10-01-11, 02:33 AM
hi guys. the rear passenger side exhaust bolt looks broke off and the way it looks it's close to the head. i've got out broken exhaust bolts out before but not on aluminum heads. does anyone know of a trick to extract a broken bolt without pulling the head? it looks like i might be able to get at it from going through the wheel well.i imagine you have to be careful with heat on these heads. thanks for any input

outsider
10-01-11, 07:54 AM
I thought the 94-96 fleetwoods have cast iron heads, not aluminum.

csbuckn
10-01-11, 10:30 AM
I think you're right Outsider, they have iron heads.

Taking pics of your endeaver? Probably a few people that would like to see how do this, including me.

turbojimmy
10-01-11, 10:59 AM
Yes, they're cast iron heads. Unfortunately, I don't know any tricks to getting them out. When I did mine the engine was out of the car.

Stingroo
10-01-11, 11:09 AM
Just had a discussion about this very thing on the wagon forum.


Quote from a member there:


Heat it up hot with a cheapie propane torch, inside the hole and outside. Then melt a wax candle into the hole, burn it again, then douse it with cold water, then heat again.
Try to remove it while its hot.

When you're drilling use a variable speed drill and turn it slowly and keep it a little wet.

Nick

newside
10-01-11, 11:35 PM
thanks for the correction guys, i don't know where i got aluminuim heads from

jayoldschool
10-01-11, 11:51 PM
Manifold has to come off. Use an impact through the wheel well with wobblers and extensions to get the remaining bolts out without breaking. If you are lucky, there will be a stud sticking out that will just spin out. This happened to me on one on my SS. Even if you can't turn it, it will be easy to get out, IF you heat it with a torch. If you are unlucky, the bolt will be broken flush or below the head. If this is the case, the best approach is to weld a nut on and unscrew. The heat from the weld will break the corrosion, and the MIG wire won't stick to the cast iron head. Replace all with grade 8 hardware, btw. While your manifold is off, cut out the bar that is in between the ports, and use the factory steel gasket when putting things back together.

Stingroo
10-02-11, 12:10 AM
Why cut the bar out? Do the factory manifolds warp easily?

jayoldschool
10-02-11, 12:58 AM
They don't warp, they break in half. GM issued a TBS to cut the bar out if the manifold is off/being replaced. Your L05 manifolds are different, though.

Some come pre-cut these days:

http://images1.carpartsdiscount.com/auto/archive/pictures/44472/515/1/P/62F1BD5/chevy_caprice_1996_exhaust_manifold_kit_oem_125567 31.jpg

Stingroo
10-02-11, 10:52 AM
Oh, yeah I know mine are different. I have headers anyway. Hooray Florida! :thumbsup:

That's interesting. Does that cause the whole manifold to crack? That's craziness.