025 Oil Pump Question

[drf255]

Happy Thanksgiving

Rebuilding an old 025. The oil pump and clutch assembly contains the large washer between the clutch and the worm gear.

I hope I can describe the problem correctly.

The worm gear fits onto the crank and seats to the C clip correctly. The washer sits above the worm drive onto the flat on the crank and doesn't seem to contact the face of the worm.

When I install the clutch, the worm gear becomes tight and tough to move. I've repeated the assembly numerous times with the same result. The worm was lubricated with oil and moves perfectly freely without the clutch installed.

I haven't had this issue on the last 2 o25/250's I've rebuilt. Is this just a sign it needs the worm gear replaced?

 

[drf255]

Bump

 

[Rookie1]

Make sure nothing is stuck in there below the worm gear.

 

[drf255]

Nothing stuck, and the washer sits on a flat on the crank above the gear face. The only thing I'm wondering is if the drive wire is bent a bit and contacts the back of the washer when the clutch is torqued down.

Wire and gear spin freely until clutch is torqued.

 

[Rookie1]

That's possible. Do you have another saw you can borrow one off of? Maybe smear a little grease on backside of washer and put clutch on. See if wire makes mark on grease.

 

[drf255]

So....

The engine side of the worm gear had a small amount on plastic that leaked over onto the brass. I shaved that off, emery clothed the clutch side and all is good now.

Btw, a Chinese replacement from Hutzl was super tight on the crank, unlike the stock one.

 

[Rookie1]

Good to hear you got it.