General Tech Oil Pump Woodruff Key

[KVH]

My new Woodruff Key for the oil pump shaft fits too loosely, and if I'm not careful it falls out, almost into the cam gear area or down to the oil pan. I realize it won't go anywhere once I'm done timing the car and installing the distributor, but it bothers me that there's so much play. My older key fits better but appears dinged up a bit. In fact, I had a heck of a time adjusting it for reuse if I go that route. I fine sanded out a small burr, and I can reuse it.

Is this another example of "why did I get a new one," or have others had experience relevant here? Is the "play" something I can ignore?

PS It's not the shaft. I have a new one to compare, and it doesn't solve the Woodruff Key issue.

 

[Gliderman8]

I had a similar issue….. not on my car but on my scooter. The woodruff key that keeps the flywheel in position was slightly small. I used some fractional shim stock in the keyway, then pushed the woodruff key in.
It’s been a couple of years and I have not had a problem.
Where are you in AZ?

 

[DrEntropy]

"New" is no guarantee it's "right". I'd opt for the old key. They should be a nearly interference fit both on the shaft and gear. Loose and you get premature wear, odd timing issues and eventually some "ticking" sounds hard to identify. Maybe get new keys from several suppliers?

 

[bobhustead]

I would buy a few keys from various (including hardware chains like ACE) to get a better fit.
Bob

 

[KVH]

I went to Ace here in Az. I'm pretty sure the box had a "designated" size the contents of which actually varied slightly. If the one I bought is too floppy, I'll get a few others until there's an "interference" fit as suggested above. I'm concerned about damage or premature wear to the distributor drive gear and mating groove. I'll be 93 years old by the time that happens, but I'm big on planning (and worrying).

 

[Graham H]

My fix for this is to use a centre punch and punch some pop marks in the part that fits in the shaft and tap it in and your good to go

Graham

 

[DrEntropy]

My fix for this is to use a centre punch and punch some pop marks in the part that fits in the shaft and tap it in and your good to go

Graham

If the key is sloppy in the shaft it's also sloppy in the gear. Dimpling the key will only hold it in place until the shaft slop knobbles them down.

I'd take the time to find the key that fits correctly.

 

[KVH]

Headed to hardware store with calipers now.

 

[Sarastro]

One problem is that there are both metric and English sized keys. You might have a slot for one with a key for the other. This is a well known problem, for example, with the water pumps.

 

[bobhustead]

You're gonna need a micrometer, not a caliper. Can you take the part with the groove with you and try it for real
Bob

 

[DrEntropy]

You're gonna need a micrometer, not a caliper. Can you take the part with the groove with you and try it for real
Bob

If no mic's, carry the pump gear with. And the old key to compare profile.