FJ40/2F carby; rich idle.

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Why would you be buying either at this point?
The advice you got was to fix the vacuum leak and check out the ignition.
If you do find out that you need a carb, I had better luck with a rebuild than I did with a new one. If you are detail oriented and meticulous, you can do it yourself. If not, you'd probably be better off with a new one or paying someone else to do it.
 
edwjmcgrath said:
Why would you be buying either at this point?
The advice you got was to fix the vacuum leak and check out the ignition.
If you do find out that you need a carb, I had better luck with a rebuild than I did with a new one. If you are detail oriented and meticulous, you can do it yourself. If not, you'd probably be better off with a new one or paying someone else to do it.
Click to expand...

Because I'm waiting for my manifold gasket to arrive (post is awful here in Oz, 9 days from the east coast) and am just investigating all avenues in case the manifold leak doesn't fix it.
I'll replace the manifold, the gasket (already replaced the studs in the head as 4 of them were bolts) and have a vacuum gauge and timing light on the way.
If that doesn't fix the issue, it's nice to already know the information I need.
 
Old manifold destined for the scrap heap, new one all prepped, painted, faces meticulously cleaned and awaiting a gasket.
The PO had decided that studs just weren't for him so had removed all but two of them. Replaced them with ones out of another head I have here. One thread was super tight and he'd spaced out a bolt with about 5 different washers and this was where the leak was as well. I managed to sort the thread out by carefully winding a bolt in, backing it out and increasing how far in I put it by a few degrees at a time, not moving it in until I was sure it was free.
Hopefully this will be the solution to the problem.
ImageUploadedByTapatalk1411999069.019392.webp
 
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FWIW, the factory only uses 2 studs at the center of the manifold to help hold everything in place. The other fasteners are bolts.

Retorking is a good idea.

Be aware that the cause of mani leakage is usually warped manifold faces. To permanently correct the problem the mani pair needs milled flat on one side, and the boltholes need spotfaced flat on the other side.
 
The only time going to all studs is an issue is when trying to R&I the manifolds in a crowded engine bay. If your engine bay is not full of USA smog crap it should not be a problem.
 
For the inner exhaust ports, the only advice I could give is the machining of the intake/exhaust together to get everything flat.
For the carb studs--you may be able to use a helicoil in the holes, since the carb doesn't need to be torqued that much. Another option would be to drill out the holes and retap.(my choice)--or, you could look for a better mani--one that had the carb studs ok.
The carb kit you listed in the first post is severly lacking.-the gaskets are rough(and don't look right) and the accel pump piston is made of some plastic type stuff--not leather.
RockAuto can sell you the correct carb kit(probably a 791B)--parts are from Standard Motor Products--very good stuff.
 
Yeah, I'm leaning towards a helicoil, they do have an odd tap though and I'm hoping I can get the thread deep enough into the blind hole in the mani.
The problem I have is that I'll need to send the mani away to get it machined and spot faced (I live in a remote area). A real ball ache and added shipping costs as well although it does seem to be the only viable option.
 
I think they are 12 mmX1.25 thread(depending on your head casting #)--I think SOR has them. You can get the bottoming tap from MSC Direct. If yours are 10mm, you could drill out to 12mm and use the MSC tap, then get the studs from SOR.
 
FTR, the carb mounting studs are M8x1.25.

The manifold to head fasteners are mostly M12x1.25.

And yes, the manifold is not gonna seal if it has not been milled & spotfaced. It warps over many heat cycles. Once it's milled it will stay straight for a long time.
 
Hi usernametaken
I had the same problem with my manifold .
I had to machine the extractors and manifold together as already stated.
For the stripped thread I use thread serts. These are a metal insert. I find them better than replacing a stripped helicoil.
If you can get the parts to me at a reasonable cost I will run them through the shop as a job for myself.
For cheap freight rates try Interparcel .
Morning freight rates are cheaper than afternoon rates . Why ?
Cheers




...via IH8MUD app
 
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