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cayuse60
03-31-2008, 02:37 PM
Removed the oil sump cover for normal maintenance and cleaning. Found a gear tooth in the bottom. Clymers advises the oil pump drive gear does loose teeth. The previous owner told me he had the oil/water pump resealed.
I pulled the pump assembly; drive gear has all it's teeth. I am guessing the original drive gear had been replaced with the reseal of the pump assembly.
How common is oil pump drive gear teeth breaking on K bikes?
TIA
deilenberger
03-31-2008, 02:44 PM
Tim,

I've never heard of it happening and can't even imagine how it could happen. The oil pump is run right off the secondary shaft (output shaft) and having a tooth break off seems just about impossible. The two gears mesh - and both have all their teeth?
cayuse60
03-31-2008, 04:58 PM
Tim,

I've never heard of it happening and can't even imagine how it could happen. The oil pump is run right off the secondary shaft (output shaft) and having a tooth break off seems just about impossible. The two gears mesh - and both have all their teeth?

Don,

What is interesting is the gear tooth is an exact match for the drive or driven gear in the oil pump.
With Clymers making a point of inspecting these gear teeth my interest was in the failure rate.
The drive gear is easily replaceable. The driven gear (large) does not afford easy replacement.
I am replacing the assembly with all new. Had weep hole leak.
roy
04-01-2008, 06:54 AM
I agree with Don on this. This is based on 25+ years working on hydraulics around gear pumps.

These gears are machined from solid steel. The shaft and gears are all on piece. The only way I could see one of these teeth breaking is from strees ckacks while machining and that would be very unlikely. At the low pressure these pumps run at those gears should never wear out.

Exceptions to this are dirty oil or low oil and both of these would typically ruin the aluminum gear housing before breaking a tooth of of the gear.

The only way there could be a broken tooth laying in the pump would be if it was trapped in the outlet port some how. If it worked loose it would jam the pump and cause major damage.

Roy