I have a 1980 Arctic Cat Panther that has low crank pressure for the fuel pump. It doesn't seem like it is pumping enough fuel to keep the machine running. The crankcase seals have been replaced. I would really appreciate some help on where to go from here. Thanks!

Does the bottom end have any fuel in it? In the past on my sled(s) I've had to disconnect the fuel line to the carb, pull the impulse line off, pull the spark plugs, and pull the engine over multiple times to get the fuel out due to flooding/hard starting. This sounds like the same scenario.

Jon

How's your compression. Could be losing through the rings, or hole in the piston. This would cause low pressure. Make sure the base and head gaskets are OK. Could the fuel pump be bad? Iced up possibly? Jets in the carb aren't clogged up are they?

Good Luck!

D

Good Compression, good spark. I have 80 Panthers and the one that runs seems like it has more crankcase pressure to operate the fuel pump. I hooked a fuel pump vacum tester up to the crankcase and it hardly moved the need. Are there any internal seals on the crank that could go bad? Thanks!

Edit:


I HAVE 2 80 PANTHERS.

Well, I split the crank and found out that the seal in the center of the crank is bad. this caused very low if any crankcase pressure, which resulted in the fuel pump not working.

Possibly the PTO seal is shot too. That caused my Chaparral to go bad. I would say that it's either the PTO seal, or the seal in the center of the crank.