Subject: Re: loop pan as sump extender?
Author: Patrick Hayes
Date: May 5, 2005, 4:49 PM
Post ID: 1718819400
Greg Bender wrote:
| So, Skip so simply states, "Why don't you just cut the bottom off a loop oil pan and use it as an extender?" |
| Any thoughts on this approach? |
Well, yes. The concept of a sump extender is NOT to give you a larger
sump capacity so that you can carry more oil. Instead, the idea is to
lower the level of the sump oil and thus give you a larger crankchamber
AIR capacity. The larger air capacity tolerates the pulsing air below
the pistons better and has less tendency to blow past seals and gaskets.
You're idea of a makeshift extender SOUNDS like a good one, but wait.
On the loopframe, the oil pickup hangs down from the oil pump. You
could lower the engine over the top of a 55 gallon drum and the only oil
that will get fed to your motor will come from the top 2" or so.
You normally use 3 quarts of oil in a loop. The oil pickup is just
about 2" into the oil puddle. Lower the sump and you lower the top
level of the oil puddle. Now your pickup is perhaps 1/2" into the oil
puddle. Good way to suck air in a curve or bump!
The Tonti frame motors are designed differently. They take their oil
from the bottom of the sump through the castings. Thus, you could lower
the sump 3' on those motors and the oil still comes from the bottom.
Very easy to install sump extenders on these Tonti motors.
I once owned one of the Cycle Innovations sump extenders. It included a
spacer for the oil pickup so that the pickup on the loop was dropped the
same distance as the drop in oil level. There were two different kits.
One for the gear drive cam engine and one for the chain drive cam
engine. They have different oil pump configurations.
I sold mine (the gear drive style) with my Eldo to Greg Field. He sold
it on elsewhere and I don't know its location now. The other chain
drive unit belongs to a chum across town.
Patrick Hayes
Fremont CA