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TR2/3/3A TR3 Water pump replacement
- Thread starter Gordon_Dedrick
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Gordon_Dedrick
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The old pump is leaking badly. Do I just take off the whole unit and buy a new pulley and key to fit the new Moss replacement pump?
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I bought a Moss TR3 water pump last year. The keyway in the shaft was 3mm while the keyway in the OEM pulley was 1/8. Moss did not then have a 3mm pulley. I had to have the shaft machined to the dimensions for a 1/8 key.
Bob
Bob
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Yes, you'll need a new pulley as well. The pump, pulley and key that I got from TRF a few years back fit perfectly. However, I added some Loctite RC601 to the joint anyway, just for insurance. I found out the hard way that the pulley must be a light press fit onto the shaft; just the key and nut are NOT enough to keep it secured. (Fortunately, the guard on my electric fan kept the pulley from hitting the fan and/or radiator.)
Check for interference between the pulley and pump; I've heard stories of replacement pumps needing to have some of the casting ground away for clearance. But again, I had no trouble with the parts from TRF.
Not necessary if you keep the stud, but if you want to convert back to the original "one bolt" configuration, don't forget the bolt has to be installed in the pump before installing the pulley. Have to get the right hole too, they aren't evenly spaced (so it only goes on one way).
Either way, get all the nuts started on their studs, before spinning them down to hold the pump against the housing. Otherwise there may not be clearance enough to start the other nuts.
Check for interference between the pulley and pump; I've heard stories of replacement pumps needing to have some of the casting ground away for clearance. But again, I had no trouble with the parts from TRF.
Not necessary if you keep the stud, but if you want to convert back to the original "one bolt" configuration, don't forget the bolt has to be installed in the pump before installing the pulley. Have to get the right hole too, they aren't evenly spaced (so it only goes on one way).
Either way, get all the nuts started on their studs, before spinning them down to hold the pump against the housing. Otherwise there may not be clearance enough to start the other nuts.