Board index Flathead Power-Technical Questions, Answers, and Suggestions Knuckles Knuckle oil pump?

Knuckle oil pump?

Moderators: Curt!, Pa

Post Tue Jun 17, 2008 8:06 am
Anyone have any experience with V-Twin's replica 41-47 oil pump? Alternatively, any leads on an original one in good shape (obviously the best way to go)? Any tips greatly appreciated.

Post Tue Jun 17, 2008 2:30 pm

Posts: 923
Location: South Provence of FRANCE

listen this one :
the V-TWIN oil pump i have had in my hands just DIDN'T WORK !
coz ...the two gears were TOO MUCH thick !
and also coz the two half-bodies of the ppump didn't match correctly together ...

So :
just tight correctly all bolts ...
and automatically BREACK this one + damages in the motor .
COOL , NO ?????

you know what ?
V-Twin is just V-Twin ...and will never be something BETTER !

d'you want to hear some about the "READY-TO-START" knuckle motor V-Twin sent me ????
a....real.....shit !
just assembled by a ten years old kid ...but NOT by a professionnal !
it's too late now and i am too tired to tell you the thousand shits i have found in this motor .
i could write you pages and pages .
that's SIMPLE :
all the motor has been dismounted .
and we have MADE the work by OURSELVES !
pistons , flywheels , cylinders , heads , cam and gearing ....and also the oil pump .
absolutely NOOOOOTHING was correct .

i was not waiting for an S'nS' brand new motor ! , but just for a correct motor.
"ready to start" just as they said in the book .



we all know this . Okay .
on a 100 / 500 Euros part Okay : we are ready to add sweat and neurones for "that perfect fit"

but for a 9000Euros part THIS IS NOT NORMAL !!!!
Last edited by milwaukee belle on Wed Jun 18, 2008 1:38 pm, edited 1 time in total.

Post Wed Jun 18, 2008 7:52 am

Posts: 62
Location: Texas' Big Bend country
Howdy Brent,

I have an OEM pump that includes the inner and outer cast iron body pieces, the intermediary steel plate, chain oiler needle with jam nut,and the return gears, all in good condition. It is missing the check valve balls, springs, and caps as well as the drive shaft and feed gears. I don't have the centrifical rotator or vanes either. Send me a PM if you're interested and maybe we can work something out.

--- Randall

Post Wed Jun 18, 2008 9:03 am

That's one of the nice things about iron pumps: if the parts look OK (no scoring, broken ears, etc.) they're probably good.
You should be able to make up a good pump out of bits from eBay without too much trouble.
JM2¢: you can tighten up the body casting slightly by simply lapping the gasket surface on a piece of thick plate glass (old mirror works well); this reduces clearance between the gears and the body. If it's too tight, lap the gears to like .002-.003".
I normally lap the gears on both sides a few strokes just to see if the tooth edges are raised at all, which sometimes happens if some grit momentarily stalls the pump.

Post Wed Jun 18, 2008 3:55 pm

Posts: 24
Location: My-am-mah, Flor-a-duh
Since we are on the subject of after-market oil pumps; does anyone have experience with the Rev Tech version? I picked one up a few years ago, new in the box, and wanted to use it on my 46 EL rebuild.

1946 knucklehead
1976 shovelhead
2006 road king

Youth and enthusiasm is no match for age and treachery.

Post Thu Jun 19, 2008 1:13 pm

Posts: 79
Location: No. Andover, Mass. USA
I have had a chrome Revtech oil pump on my knuckle for better that 10 years and have had no issues other than managing theflow to the heads. Pump assembled fine and allignment went well using the turning the shaft by finger method from inside the camchest cavity.


Post Fri Jun 20, 2008 6:57 am

Posts: 24
Location: My-am-mah, Flor-a-duh
Dick, Thanks for the info. However, your response in regard to over oiling begs the question:

Over the last year I have read many, many post referencing a top-end over oiling problem associated with after-market oil pumps, regardless of manufacturer, and many “tricks” to reduce both flow and pressure, be it trimming the pressure spring or restricting the oil supply line to the heads. So the question is, what is the advantage of using one of these after market oil pumps over that of an OEM pump, as well as, if one had the choice to use an OEM oil pump or one of the after market pumps on a stock knuckle engine (restoration exactness not an issue), which would you choose.

1946 knucklehead
1976 shovelhead
2006 road king

Youth and enthusiasm is no match for age and treachery.

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