While making the pump body spacer I was comparing the oil passages for the suction side. There is a curious fluid path. The oil is drawn p the pickup tube all the way to the top of the pump body. There the oil makes a 180 degree turn and is drawn back down to the head with the pickup tube. On the pump head there is a horizontal channel that the oil must be drawn through. That channel is ridiculously narrow/small. The narrow point on that channel is 1/4" wide and a bit over 3/16" deep. That's the equivalent area of a 1/4" diameter hole. Seeing as how pumps push better than pull... that tiny passage just sounds like an awful flow restriction.
The pump head that I measured this on is the older straight pickup design but I assume the angled head would have the same restriction. If it does... when/if I install this pump on the engine I am considering undercutting the pump head (without disturbing the surfaces the rotors seal against) to enlarge the flow path into the pump to be as large as practical. I'll post pictures later showing what I am talking about.
Doug L.
--Previous Message--
: Hmmm that doesn't sound good, it's really
: having to work to make pressure.
: Another consideration would be the oil
: pump itself not making enough pressure,
: due to a suction or pressure leak.
: Glen
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