Brent A.

While attempting to pull the oil pump out I noticed the shaft seems to have quite a bit of end play.
I measured the in-and-out movement at .0520". Is this normal?

1991 S4 with 32k miles.

Mrmerlin

Is the pulley loose?
I would remove the pump and inspect it and see if you can ID it via posted pictures also use the part number it has stamped on it
I know its just a casting # but the newer pumps have a different #

Most of the pumps that I have replaced are due to a shaft that has a bit too much wiggle of the shaft side to side,
this is due to running with an over tightened Timing belt, and or using an oil thats too thin.

That said on a car with only 32K miles I would not expect any issues with the oil pump, IOW its OK

Brent A.

The pulley was good and tight. I didn't notice the shaft movement until after the pulley was off and I attempted to remove the pump. The shaft has no play at all as far as side to side movement goes.

Brent A.

I attempted to upload a short video of the movement, but can't seem to get it to upload so here are two screen grabs of it.

Brent A.

Mrmerlin

looks like the spacer for the aluminum gear is still in place,
this gets removed when you install the steel gear

Mrmerlin

that play may be OK ,
NOTE the drive gear is surrounded by oil when its running,
have you noticed any issues with oil pressure?

Brent A.

Oil pressure was normal. Probably not and issue as you said.
I'll check the end play again when I get the new o-ring on and re-assemble to see if it's the same.

Thanks.

Bigfoot928

hows the gear look? how wide is the wear patter vs the old belt?

Mrmerlin

I like to use DC111 on the O ring seal for the pump

Brent A.

Good to know on the DC111. Thanks.

The pump gear is in good shape. No visible cracks, coating is intact and belt tracking is spot on.