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3406C exhaust manifold

Acoals · 2023-03-30 20:39

I had several broken studs on the exhaust manifold, took the manifold off and fished the studs out. The three piece manifold came off in one piece. Should I separate the sections and clean them and put them on in pieces? From poking around on the internet it looks like the Cat manual says to put some kind of sealant on the joints?

Replies7
  1. #1Mike L2023-03-30 20:48

    I’ve dug out dozens of broken cat manifold studs. Never separated the manifold. The bolt holes were oval shaped to allow some relief and heat will keep the sections sealed up.

  2. #2Acoals2023-03-31 06:15

    Sounds good . . . thanks . . . I didn't want to take it apart anyway

  3. #3JD955SC2023-04-01 07:39

    I don’t separate them seems like inviting too much trouble BTW if you ever have to drill them out Cat has guide kits. Without them some people are gifted but many like me can only drill a crooked hole and I’ve seen a few where the driller punches into the water jacket.

  4. #4Acoals2023-04-01 12:04

    I did drill have to drill several studs out. I hear those guide kits are the way to go, I just never had one. Those great big 3/8 studs in cast iron seemed a lot easier than the little 8mm studs in the aluminum heads of a V8 in a pickup.

  5. #5Mike L2023-04-02 20:37

    I’ve never used a guide kit. Just be patient and go easy. I do have a pneumatic mini die grinder that works good on the studs that seem to be welded in. Drill it as big as you dare and then use the grinder to split the stud into 4 pieces. Dig them out, run a tap in the hole and your good to go.

  6. #6Truck Shop2023-04-02 21:45

    I use these made in several sizes. Winzer Cyclone.

  7. #7nowing752023-04-13 11:46

    we had ordered the sealant a while back. If i remember right it was stupid expensive.