DH106

I have a JetCat P20 which I'm running on a test stand, but it no longer reaches it's full power RPM of 245K - it gets to about 215K, although the 'commanded RPM' shown in the lower right of the GSU does indicate 245K, so it's not a radio calibration issue.
It looks to me like the pump power is reaching a limit/cap - but I can't see anywhere in the settings that this can be adjusted.
What are typical values for the pump power figure in the lower left of the GSU when running? Mine reaches 4.2 and doesn't go any higher - how is this limit set?

Thanks in advance.

Dave Wilshere

Run it at full power and hold the set button down, the rpm should increase to 245 and set. I can’t remember the max pump value on the P-20, you must be getting close. Your sure there is no restriction in the fuel system? What tank was it running before and now?

DH106

Thanks for the advice Dave - I'll try that tomorrow.
Pretty sure there's no restriction in the fuel system - the fuel piping is new, but it's the same 3mm OD/2mm ID as the original tubing supplied (and it has to be longer than usual for the P20, the required 1.1m loosely coiled on my test bed between the tank & engine). The filter is a hi-flow type.

Dave Wilshere

OK, Festo 3mm tube should be 2.5 I/d
Length is correct 900-1100mm works

Dave

DH106

Ah - okay, perhaps the tubing I'm using is too narrow & restrictive at 2mm ID and that's the problem.
Ref: the GSU - there doesn't seem to be a [Set] button on mine, could this be the [Change Value] button?
Thanks.

Dave Wilshere

If it’s the old rectangular GSU it will be Manual Red button
You need Festo tube ideally. Sounds like you have retract tube

DH106

Yes, it's the older black rectangular GSU. I also have one of the mini-onboard GSU units, but its buttons are the same as the black GSU.
I'll try and source some Festo 3mmOD tube then - it's not some thing that you stock is it Dave? I notice that you have 4mmOD JetCat tubing?

Dave Wilshere

Mini GSU or older it’s the Manual button.
Yes, several hundred meters 🙂 If you search Festo 3mm tube, or its on the same page...or give me a call

Dave

DH106

Thanks Dave - have ordered some 3mm tubing & a few other bits n bobs.
Shame they don't do clear/transparent tubing - so you can see if there's fuel in.

Dave Wilshere

Seen it, should have clear...

DH106

Okay - gimmie clear if you have it Dave, otherwise yellow.

Dave Wilshere

I sent the yellow ordered, but found 1m clear, so threw that in for nothing.

Dave

DH106

Wonderful - thanks Dave :-)