582 fuel pump help

[KFfan]

Ollie, I agree with you.
The manual however uses the word "should" leaving the final mounting orientation to the installer.

The one on my model 2 is mounted vertically and rather high with respect to the fuel tank. I plan on remounting it as well as adding an auxiliary electric pump.

[t j]

However you mount it try to keep the pulse line as short as possible. The Rotax manual says no longer than 20 inches. Less than 12 is best.

My Kitfox builder's manual has the pump mounted horizontally high on the firewall. The problem is on the 503 the pulse port is near the lower front of the engine so the shortest I could make the pulse line was 21 inches.

It seemed to work fine during the static engine break in but on the first flight of about 30 minutes the weep hole spewed oil all over the firewall.

I tried everything to fix it. Asked questions on several forums too. The overwhelming response was no one had ever had anything leak from that weep hole and that my pup definitely had a ruptured diaphragm.

I could not find any holes in the diaphragm so ordered a new pump from CPS. That new pump DID NOT have the weep hole. Mike Stratman at CPS was adamant in his Tech articles that the pump MUST have the weep hole. Go figure. I returned the pump to CPS and they sent one with the weep hole.

That new pump did the same thing...spewed oil all over the firewall during flight.

I rigged a catch tube under the pump and went and flew for an hour to see how much oil it was dripping. It was about an ounce and a half.

Then called CPS to ask some questions. He was speaking from a script and WOULD NOT answer my questions.

I tried asking on the forums some more and got the same old answers. "Your fuel pump diaphragm is ruptured" or "Your engine has excessive blow by"

Then......a guy on the Matronics Kolb List...that's a good place to ask 2 stroke questions...says "Your pulse line is too long".

I mounted the pump horizontally under the carbs so the pulse line was about 8 inches long. That cured the problem. Not one drip out the weep hole sense.

[KFfan]

Thanks for passing along your insight/experience tj!