The Tillotson HD Carburetor has not been in production for more than 40 years.
But this has not stopped vintage snowmobile enthusiasts from enjoying their all original vehicles.
Due to the age of these carburetors, parts and support are limited. We use mostly aftermarket components, but where parts are most critical to the tuning and performance of the carburetor, we have made components superior to all other aftermarket kits.
The most crucial of those components is our fuel inlet seat. The number one problem with Tillotson HD carburetors is replacing the needle and seat with a poorly made fuel inlet seat.
How do you know if you have a poorly made seat? At idle and low speed, your carburetor is flooding out, especially out the high side nozzle. Many believe this is due to the check valve in the nozzle, but this is not the case. Your nozzle needs to have more airspeed or more signal to pull fuel off the high side. If it's dumping fuel, then it's because nothing is controlling the fuel to the high side circuit. You will also see your high and low side needles do very little to tune out this problem.
Cheaper kits recognize this problem and attempt to fix this by using an overly stiff inlet tension spring. This only adds more problems.
We have helped many customers fix this problem simply by using our fuel inlet seat. Our seat is made in the USA and designed to use the Tillotson OE fuel inlet needle of current carburetors. This not only fixes the issue but allows us to use the proper inlet tension spring for better tuning and performance.
We highly recommend using a pop-off/leak-down tester and the 714 fulcrum arm height gauge to check your carburetor for rebuilds.
P20-RK EC Pro Rebuild Kit for Tillotson HD Carburetors (Non-accelerator Pump) replaces Tillotson RK-86 Kit
• Main Metering Diaphragm
• Main Metering Diaphragm Gasket
• Fuel Pump Diaphragm
• Fuel Pump Diaphragm Gasket
• Brass Fuel Strainer Screen
• Fuel Strainer Cork Gasket
• .437 Welch Plug
• EC HD Fuel Inlet Seat
• Captured Inlet Needle
• Captured Fulcrum Arm
• Copper Inlet Seat Gasket
• High/Low Side Needle O-Ring
• 021 Inlet Tension Spring
• 91A-351R Fuel Inlet Cap
• 125-512 Fuel Filter