Hi Pete,
I recently ordered a replacement fuel pump for my Ram 500 from Modellbau USA. What they sent me is a Hausl ZP28028. The pump seems to work fine on my test stand. I noticed that it did not have an EMI filter attached to the back of the motor so I am afraid to fly it in my plane fearing radio interference problems. Hausl sells their pumps with and without EMI filters. The correct one would be a ZP28028F. I called Alberto at Modellbau USA and he tells me that the EMI filter is not needed, and that he has been flying his for several years without one.

Personally I think it would be foolish not to have one since most of the EMI is generated by that motor, my old RAM pump has an EMI filter attached and so does all of the competetion that I am aware of, and any electric flier motors come with EMI filters or capacitors on the motors. So I bought and installed one on my new pump and am now ready to put it in my plane.

You can get the pump from several sources;
http://www.modelltechnik.at/eindex.htm
http://www.modellbau-usa.com/catalog...sort=2a&page=3
http://www.nades.net/products.htm
http://www.wrenturbines.co.uk/accessories.php#cat3

Joe