JD500

[WiscoBryan]

I have a 1973 JD500. When I get it to run( several pulls before it starts) the return gas line has a lot of bubbles in the gas. Is this normal or is it 'suckin air'? It has a Walbro WDA32 carb.
Where can I get crank seals for this sled?

[HoosierDeereMan]

Its normal for the return line to have air bubbles in it.

If it takes several pulls to get it started it sounds like the carb may be losing prime. Make sure the check valve in the pick line inside the tank is working properly. Also make sure all gas supply connections are tight and secure. Make sure to check the impulse line from the crankcase also. Over time the pump diaphagm in the sandwich plates of the Walbros will stretch and get weak. A good cleaning and rebuild kit might be in order.

You used to be able to buy replacement crank seals through Central Snowmobile. I haven't looked at my new catalog so I don't know if they are still available or not.

[jdjason]

seals are also available through parts unlimited as well as the rebuild kit for carb 10 bucks and your done and the carb rebuild is not very involved
winderosa carb kit number is 451410 made in the u.s.a. if that matters to you

[WiscoBryan]

Hi,

Thanx for the help. I'll check the parts you listed and let you know what happens. I'll have to get out the manual to find the check valve in the gas tank. I took the carb apart and cleaned it making sure no carb cleaner got on the rubber. Will probably order a carb kit and re-do the diaphragms. While I'm still here, does anyone know where the wires to a tach goes for the 500? I know where to route the yellow lightbulb wire but I need help on the solid Red (power, 12V ?) and the yellow w/red stripe (to alternator?) wires. The yellow/red stripe wire has a 0.1Amp fuse. I have the wiring diagram but would like a bit of reassurance b/4 I hook them up. Anyone else put a tach in a 500?

[jdjason]

wiring diagrams are available on jdsleds.com and in a clymer manual available on ebay noe 11-6-08