TRW ish PS Pump Rebuild, retaining rotor to shaft?

[rakort]

so originally the pump slipper rotor was held to the shaft with a key and a constant cross section retaining ring (similar to a snap ring) and that ring got ate up during the operation of the pump. Probably one of the weak points on these pumps. So I've got a snap ring that fits well, but still not "tight" in the groove so it will rotate under operation and likely get ate up again. Was considering skipping the problematic snap right and using some modern technology retaining compound (loctite) to retain the rotor to the shaft. Thoughts?

Once I solve this issue the pump will be good to go.

 

[miller]

Thoughts?

Me? If it was mine, I'd measure the groove depth/width, and find a bearing house. They would have the ring you need, if you can't find the correct one.

 

[Yatzee]

so originally the pump slipper rotor was held to the shaft with a key and a constant cross section retaining ring (similar to a snap ring) and that ring got ate up during the operation of the pump. Probably one of the weak points on these pumps. So I've got a snap ring that fits well, but still not "tight" in the groove so it will rotate under operation and likely get ate up again. Was considering skipping the problematic snap right and using some modern technology retaining compound (loctite) to retain the rotor to the shaft. Thoughts?

Once I solve this issue the pump will be good to go.

View attachment 542600

What you need are called "spirolox" coiled retaining rings which you can source from a machine shop, bearing supplier and probably online. You need to know the diameter at the bottom of the groove and the groove width. You can stack them for the proper width of groove.
https://www.smalley.com/retaining-rings/spirolox

 

[rakort]

Yeah, I've been researching these retaining rings..I can't get the ideal one from McMaster and not sure if I can buy less than a million pieces from the manufacturers

The one below is about as perfect as it gets, but the groove diameter is still .020" less than the ring diameter so it will still be free to rotate on the shaft which I think will be an issue.

3 spirolox will be about right for the .055" groove width, but their ID is still larger than the groove diameter.

 

[69Bee]

This is not a proper application for a "Spirolox" clip. What you need is called a "Cir-clip". I believe the groove is rounded for a round clip, and the Spirolox uses a square groove. There are a few different types, but the link shows what you need, and what was originally used.

https://www.springmasters.com/sp/external-snap-rings-din-7993-a.html

 

[rakort]

So this one is a square groove. I suspect that this is an aftermarket pump so what may be applicable from other pumps may not be here.

 

[rakort]

I suspect that this is an aftermarket pump so what may be applicable from other pumps may not be here.

Hence the TRW "ish" in the subject line.