Fixing airpump mount
 

Hi all,

so I was working last night to remove my airpump, fit a set of pulleys and the FFE idler pulley… and encountered a siezed bolt on on one of the pump mounts and the thermostat mount. Both ended up sheering off, despite lots of wd40 and the usual tighten and loosen procedure.

tried drilling and easy-outs, but the airpump mount ended up cracking off.

What do people normally do in this situation? Was thinking about getting it welded, but can that be done with engine still in the car? Any precautions required with electronics/sensors etc?

is aluminum brazing or JB weld a viable approach?

for the thermostat bolt that’s still in there, was thinking about drilling out and using a helicoil, or just retapping one size up, since that’s also being very stubborn. Any suggestions on that?


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there is no fixing that reliably in the car. welding would work but if youre pulling the housing then you can replace it. keep in mind its old cast aluminum impregnated with years of coolant. the stock water pump housing doesnt weld so well most of the time. seeing youre in california i guess you NEED the air pump so you have to do something.......

i would advise replacing the whole housing. its dumb but any "fix" will only be temporary. having to keep the air pump really makes this whole thing stupid. in any other circumstance you would simply delete it and carry on.

^Yep, get a new or good used water pump housing. It's not too bad of a job to do in the car.

Get a new water pump housing to block gasket, new water pump to housing gasket, new OEM Mazda thermostat with rubber gasket, and MAYBE new water pump if you are feeling up to it. You may have to get a few odds and ends bolts depending on what you have, what bolts broke, and what the new housing comes with.

The OMP lines have a little retainer clip under the water pump housing, it just needs to be bent out of the way. I think you will need to remove the main pullies, just undo the 4 10mm bolts that hold it to the hub, you don't have to mess with the 19mm main pulley hub bolt.

Take your time, clean all the old gasket and RTV off of everything carefully, and any bolts/nuts/studs that can get coolant on them use some anti-sieze on the threads.

Dale

To manipulate the torch and filler wire, there's no realistic approach to do that in-car.....and get a good weld. Probably half munted the thermostat threads too looking at the drilling, even if you got it EDM'd out, when it was fully removed from the car.

I'd suggest, just get another one. You could buy the new integral filler neck housing, but with Mazda prices, it would be odds on stupid money. There's 2 or 3 used ones here from old import donors taking up space and I very much doubt I'm on my lonesome there, so I'd be searching that direction as advised above^^^.

i will be deleting it. But need the mount for the FFE idler pulley mount. Not sure if that changes anything.

but if it’s easy enough to replace the water pump housing, I’ll just do that I guess. Will look into sourcing it. Thanks for the thoughts. 1 step forward… 3 steps back….

And I think this may be the universe telling me I should leave it in the garage for the winter and do the efr8474 + vmount + fuel system install while I’m at it :)

(assuming Turblown delivers my kit in any reasonable time)

I would get this done and buttoned up and run the car to make sure you have a leak-free setup, THEN tear into the rest of the project. Always best to make small changes and test as you go.

Dale

oh.... well then that changes everything. Get a different idler. The pineapple BT pulley doesn't use the air pump mount point at all and is very good. Problem solved.... you dont have to do anything further. I'm pretty sure it works with the twins but I'm not 100% on that. The non BT version of the pulley uses the air pump mount I believe. You would want to get clarification before buying it

Even so there's a broken thermostat housing bolt. I've had about 50-50 luck repairing those. To really do a good job repairing it the thermostat housing comes off, and if you have it off already, just replace it and be done.

Dale