Paul,

 > Back on November 11th you sent out this Rhino drawing of a water pump

with

a
 > pressure tank incorporated into the pump outlet.  It seems to me that

this

same
 > idea, but with the pressure can on the pump *inlet*, would help solve

both

the pump
 > cavitation problem (by providing an elastic air spring on the inlet

side)

as well
 > as letting one set the system pressure on the pump inlet side (which is
always the
 > system's lowest pressure point).
 >
 > Can you see a way to accomplish that change?
 >
 > Russell Kent

 Here it is. I think the block outlet pipe will clear the can.
 You now have freedom to plumb in from the rad from almost
 any direction. (The inlet from the rad is not shown in the rendering.)

 Paul Lamar

------------------------
Hmm -- very similiar to what I did, with the exception that I used only the
1-3/8" pipe for the vertical. I am planning a pressurized overflow bottle
feeding the vertical standpipe.  I was concerned with mass supported by the
water pump if the 'tank' were too large.  I do plan to have a compliant
coupling between the outlet from the pump and the vertical standpipe.

There is also a space problem, at least in a KIS Cruiser.  There is almost no
clearance above the pump outlet for the reservoir on the inlet to have volume
above the pump. See my photo, I had a longer vertical tubing and had to cut
it down to get the pressure cap in place.

Bill Schertz
KIS Cruiser #4045

Bill you don't need to compress (zip) jpgs. They are already compressed.
Extra step on my end.

The Kis is a tight squeeze. The pressure can can be tied to the pump 
outlet tube for support. I think the five or so 8 mm water pump bolts can
take the shear load. I agree, we don't have much space
above the engine. Good argument for a large diameter can. 

Perhaps we will need a bump on the cowl over the pressure cap. 
With pressurized air in the top third of the  can and vent 
tubes coming from the front of the block we should be OK.

Your engine looks a bit closer to the firewall than mine.
I assume you are using the short cowl.

BTW I am not putting the rad in this position. The air will
come in over the top of the rad with a duct and exit through
the bottom of the cowl. If I tried to do it the opposite
way the oil pan would block the flow.

Paul Lamar
 
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