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I mean, not the entire pump. I KNOW I need that!
However, I'm building a pretty basic chopper running a dry primary & I was wondering which of the pipes on the oil pump I can blank off.
I'm assuming that my only real necessities are the feed, return & the 2 vents & the rest can be blanked?
In principle, every engine with dry sump lubrication needs two lines: a supply line from the oil tank to the engine, and a return line from the engine back to the oil tank, AND a vent line leading away from the engine casing, wherever that may be...
That's all there is to it; everything else is modern frippery that some ingenious engineers came up with in later years...
A friend once explained it to me in such a simple way, given the many lines on a Shovelhead engine/oil pump in the 1970s.
Once you've internalized this principle, everything becomes very easy, or maybe not...
You can argue about it for days, but the oil pump is like the heart in a human body; the pump keeps the machine alive with its pumping circulation.
If this cycle stops working, then it's the end of the machine, over and out, period.
There's a nice German saying:
"Wer gut schmiert, der gut fährt!" ("He who greases well, drives well!")
Mike
PS Anyone who wants to read and see it in detail can find all of this dozens of times on the internet.
It's been pre-filmed, sung, screwed, and recited countless times, but all of that doesn't change the simple principle of dry sump lubrication, unfortunately.
And no matter how great a company manufactures the oil pump, whether from hand-carved stainless steel or whatever, all HD BT oil pumps manufactured after 1936(?) operate on this principle.
The large Flathead models aside, those were and are a completely different story...
PSS In our former ignorance, we not only ruined one old BT engine with half-knowledge and stupidity, hoping that a new HD oil pump would fix all the problems.
Fixing these stupid mistakes later cost a lot of money; you learn from your own mistakes, the best lesson!
Last edited by Mike1956G; Mar 9, 2026 at 01:58 PM.
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Oil pump elimination
