I have an OS 61 sf-p....the one with the 4 way pump on the backplate. The pump has 4 nipples: from tank to pump, from pump to carb, a return- from carb to pump, and return- from pump to tank. Judging from the engine manual it appears that there are two holes/vents/nipples in the backplate. This engine sat on the shelf for about 6 years and I tried running it. Engine runs great, but won't idle. I notice air bubbles coming from the pump, but not from the tank.

I sent it to Hobby Services for repair, and they sent it back two weeks later, saying there is nothing they can to, because the engine has been discontinued in 1998. They also said the pump is all metal, and vitrually unbreakable, and that I should simply run fuel through it to "limber" it up again. And of course, two tanks later...same old bubbles that don't go away.

My question is, because the carb opening diameter is huge and requires (won't run without one) a pump to pump fuel in and a pump to pump fuel out. Can I just get a couple of perry pumps? If not, does anyone want to buy the engine at a really great price? It is a great motor that has about 10-12 lbs. of thrust and has more power than a OS 61 FX; and with the pump working, it would idle at 1800rpm and I have never had a deadstick. All in all, it has about a gallon of fuel through it total. Paid about $260 for it from Tower in 1997 and have original reciept.

Thanks for any suggestions!