[toddfiebig]

I got my new water pump and realized I need to get the tach drive gear out of the old one.

Does anybody have hints or tricks?

Thanks!

 

[Alfajay]

Not sure I understand your question. Beyond "remove the two 6 mm bolts and withdraw the drive", what more do you need?

 

[toddfiebig]

It is stuck in there. I suppose it is nice to hear that they should just come out after removing the bolts but mine is not cooperating. Bit tried tapping on it and soaking with PB Blaster to no avail.

 

[Alfajay]

It is stuck in there. I suppose it is nice to hear that they should just come out after removing the bolts but mine is not cooperating. Bit tried tapping on it and soaking with PB Blaster to no avail.

PB Blaster won't do anything; the parts are already well oiled.

The problem is probably due to a PO using hardening gasket sealer. Try using a screwdriver as a chisel to separate the drive from the pump. Yea, the screwdriver will mar the surface of the pump, but that's the part you are discarding anyways.

 

[toddfiebig]

I think this motor is on its first rebuild but who knows about the water pump. I tried a chisel and hammer but it did nothing. Maybe I should hit it harder.

 

[Alfajay]

I think this motor is on its first rebuild but who knows about the water pump. I tried a chisel and hammer but it did nothing. Maybe I should hit it harder.

Well, I'm not advising you to beat it to death! My point is that these parts are well oiled, and generally just slide apart. It isn't a press fit, there are no hidden setscrews, etc. So I believe the gasket is all that's holding it.

Can you twist the tach drive relative to the water pump body? Perhaps get a set of channel locs on the oval flange of the drive, and give it enough of a twist to shear the paper gasket or sealant?

 

[toddfiebig]

Jay,

That was a good idea. I threaded the old cable on and over tightened it with vise grips and it slowly started to come loose.

Thanks!

 

[Alfajay]

Glad to hear that twisting worked. Everything I know about removing tach drives, I learned from Chubby Checker.

 

[BiancaGT]

For whatever it's worth to anyone else coming across this problem, I tried the Cubby Checker method but could barely twist the tach drive, much less remove it. It was really tight in there. In the end, I had to separate the drive from the water pump casting, starting with a very sharp, wide, wood chisel and a big hammer, and gradually move up to thicker chisels. In the process, I munged up both surfaces a bit but my own, custom made, thick, rubberized paper gasket (no replacement was provided anyway) seems to have provided adequate sealing. The replacement water pump (from Centerline) has a slightly larger bore and the tach drive slid in easily.

Btw, has anyone rebuilt one of these water pumps? I realize it's probably not worth the effort, but just wondering.

 

[hans2]

I've not seen pre-cut tach drive gaskets sold as a standalone part, so you'll have to cut a new one from gasket paper to make future removal easier.

 

[Gordon Raymond]

Yes, I rebuild ORIGINAL 750, 750-101, 101 and 105 water pumps. However, other than the 750 or 750-101 pump, or the 101 or 105 pump for concourse use, this is NOT money wisely spent. The good aftermarket 101-1600 and 105 pumps are less costly than a rebuild. As the aftermarket castings differ from originals, for concourse, a rebuild of a good original 101-105 punp is worthwhile.

 

[Jim G]

Yes, I rebuild ORIGINAL 750, 750-101, 101 and 105 water pumps. However, other than the 750 or 750-101 pump, or the 101 or 105 pump for concourse use, this is NOT money wisely spent. The good aftermarket 101-1600 and 105 pumps are less costly than a rebuild. As the aftermarket castings differ from originals, for concourse, a rebuild of a good original 101-105 punp is worthwhile.

Do you need 105 cores?

 

[Gordon Raymond]

I've plenty for now. Usually concourse car builders send me one.
Thanks.

 

[Cali67Duetto]

Tach Drive gear stuck in water pump also....

Trying the method suggested by jay, will report back soon.

Thank gawd for this message board!

 

[Cali67Duetto]

It worked....

Trying the method suggested by jay, will report back soon.

Thank gawd for this message board!

The gasket or sealer did not appear to be the adhesive type. I fit a metal putty knife between the gear drive and the gear housing. The brass tach gear is a very tight fit. It did not appear to have any corrosion, it was just real **** tight! The vice grips marked up the tach flange a bit, but ill feather it with a table grinder to remove the marks.