Board index Flathead Power-Technical Questions, Answers, and Suggestions K-Models K/KH oil pump versus XL one

K/KH oil pump versus XL one

Post Sat Jun 17, 2006 6:38 am

Posts: 591
Location: Crewe, Great Britain

Querries from another thread:




Gears and oil timer drives:



Note K/XL slots are same width but taller than WL scavenge one.

The tower marked "K XL s" is an early tower with slots enlarged, closing side only, to post 72 specs

K/KH/57 to 61?XL oil pump gears: 14 teeth
delivery gears .217" thick, 5.51mm
scavenge gears .360" thick, 9.14mm

62?/71 Sportster oil pump: 16 teeth
delivery gears .181" thick, 4.59mm
scavenge gears .375" thick, 9.52mm

They were changes to oil pumps in 56KH, 62XL, maybe more, don't know for sure what for, hence the question marks above...

...Some personal disasters... Don't ask.......



Post Thu Jun 22, 2006 2:35 pm

Posts: 240
Location: Kirkland, WA, USA


I am digging in the pump now, as my rings never seat up, and it tends to beat the edges of the pistons crowns making cuts in them. This with new rods new bottom, and fresh hone. My machinist is measuring everything up today.

We are going to switch to a K style pump, from the '72 pump it has been running with an earlier XL breather gear, and stock '72 gears.

I am also likely to plug up the side oilers, as it is just flooding the bloody thing with oil. 100 miles to the quart! I am going through bores quite fast. Am at .050 over now, and not happy about it. The cutting at the top may have started when I first had it bored from .020 to .040 as I thought it was at .030.

We are hoping that the lesser oil flow of the K model pump will solve at least some of the problem. The .45 style rings that Gil from Easter MC ordered all his K pistons cut for do not work as well as the originals either. I like the K style rings, but can’t find pistons in this configuration.

If you send my an email, to I will send you pictures of what I think is a KR pump that came on my KH when I got it.

I will send you other pictures and ask you some questions also....



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