hd-t exhaust manifold leak

[sandcruiser]

my exhaust manifold has a bit of a leak where the two halves join

the fsm shows "manifold rings"

is this something that can be fixed? or do I need new manifold rings? 'cuz I don't know if can get those and don't want to be stuck with the manifold apart.

put differently: how the heck do I fix an exhaust leak that starts at the junction to the 2 parts of the manifold?

side note: Why the heck did Mr. T do a 2-part manifold?!? seems like a totally un-necessary added complication.

 

[70sguy]

Here are the part numbers. They are available, have replaced many when we have manifolds ceramic coated.
No idea why Toyota made a 2 piece set up. 12H-T has 2 piece manifold too.

If your local Toyota can't get em in I would check with Dave at japan4x4.com
Or even Ens Lexus Toyota up here in Canada if all else fails.

 

[sandcruiser]

mmmmmmmmmmmm
ceramic coating
wish that were an option for me right now

anyone painted an exhaust mani with hi temp paint? I have a can that claims 1500*F
Don't know if it is true, but seems like the cast iron shouldn't ever get that hot- even if your EGTs spike to 1500 for a spell, it takes a while to change the temp of the manifold and it is always surrounded by air that is less than 400* in the engine compartment, and the block should also be less than 500 at all time, right?

thoughts?

 

[70sguy]

Don't waste your time or money on paint.
In my experience ceramic is the only thing that will stay on the exhaust manifold.
Ceramic makes you go faster too!

 

[Macro]

I've always assumed the two piece design was to allow the manifold to grow and compress due to heat cycles...

I've got either a cracked manifold or a manifold to head gasket leak, the parts are cheap enough but pulling the manifold and turbo off I've heard is quite a mission!!

 

[Stone]

Hmm...when I had my manifold apart to be ceramic coated on the 12H-T, I ordered and installed new o-rings and rings. Not long after putting it back together, something whacked my turbine. Close inspection of the inside of my manifold revealed some blue residue...turned out to be melted o-ring! I don't know if the small pieces of rubbery material would have been enough to damage my turbine, or if it was something else...but I was damn careful when I put my exhaust manifold and turbo back together and I can't think of what else it could have been.

Anyway...it made me very nervous and I ended up not installing o-rings and just installed the two metal rings. Probably leaks a tiny bit right now...but I don't hear anything from that junction. I figure over time enough soot will build up in the gap to seal it up nicely...lol.

 

[sandcruiser]

the ceramic coating is lovely. If I can find someone to do it locally (and find orings and metal rings) I may go ahead and make it happen.

for sure, pulling the mani and the turbo takes some effort. Isn't that bad, but the combo is heavy and just about centered in the engine compartment. I found it challenging because I'm short and my arms are pretty well extended by the time I get in there. I would think that taller folk would find it challenging because, well, there's a hood there.

I'm going to go start a new thread: but anyone know the proper way to re-install the manifold studs?
All but one of mine pulled out. I've cleaned them up- run them through a die and tapped the nuts so all is clean and smooth now.

Do I use a dab of anti-seize to reinstall them? How much to torque them? I *really* don't want them to sheer off! Loc tite? Ditto on the nuts.... I think antiseize seems like a good idea, loctite seems a horrible idea on the nuts. Thoughts?

 

[70sguy]

I would install the studs into the manifold dry or with medium locktite,
Use 2 nuts locked together to torque the studs into the head, and then use antiseize when you install the nuts

 

[veiloctane]

rubber o-rings i think are just for installation as the heat would melt them away