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Thanks Todd, I was able to enlarge the
photos to 8 x 10 using PhotoShop without losing much detail. Now I can finally
say I got the picture.
Hi
Jerry;
I'm glad you were able to get the detail you needed. I
reduced them to a smaller size than I would have liked due to the large number
that I was sending. If you'd like a larger copy of any of the pics, I can send
them off-line to avoid filling the archives.
Do you find it necessary to run both EWP's
and the EBP in normal flight? Do you see significant flow increases over just
using one pump?
In normal flight I only need to run one EWP. When I only
had the one EWP it was fine for all phases of flight, but when I put the second
one in series, I lose ~30% of the flow if the second pump is off (as compared to
the single pump installation), but when second pump is on I gain ~50%. So now
during climb out I use both pumps. I can turn off the second pump during cruise.
The EBP really isn't necessary. I have the electronic controller on my primary
EWP but the second EWP is on/off. During long descents from high altitude during
cool weather, I found that the primary EWP controller would reduce flow to
minimum, resulting in a cold cockpit. The EBP provides coolant to the heater
core while ensuring a greater than minimum coolant flow through the hottest part
of the engine, while at the same time not cooling it excessively. As I said,
this is probably not required for most of you southerners.
I did notice something way back when I was still running
with a single EWP and no EBP. I was doing touch & go's on a sub-zero day and
I had the single EWP controlled by the electronic temp/speed controller. The
pump would be at full speed during climb out, then would reduce speed a little
on the downwind, then during the short descent it would go to minimum speed in
an effort to maintain engine temp. As I touched down and applied power to climb
out again the pump speed would increase again. However I then noticed the
coolant pressure which would reduce to near zero as the engine cooled, would
suddenly spike momentarily as I applied power, then within seconds would return
to normal as the pump speed increased. This tells me that I was seeing some
localized boiling during the lag time until the temp sensor sensed the increase
and the controller sped up the pump. My temp sensor is located in the EWP
adapter block that I built, so is at the exit of the coolant from the engine.
RTD's are fast acting temp sensors, but the coolant at minimum flow does take a
few seconds or more to travel from the hottest part of the engine to the exit.
I'd expect that if I'd placed the sensor at the rear end plate location (below
the oil press sensor) I would see much better response. However I installed a
bypass switch when I installed the controller which allows me to provide full
12v to the pump, so I just began to leave it on while doing touch & go's.
The engine cools a little much, but not a big deal. Now with the EBP installed
this shouldn't ever be an issue.
I should stress that it is not required to
have this or even a second pump if an EWP is desired. It just what I decided to
go with based on my environment and desire to experiment
I have a lot more room under the cowl than
you had to work with. Amazing you got it all stuffed in there. Jerry
What was that you were
building?
Todd (no BUC needed)
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