Post by Chad on Feb 16, 2004 18:29:30 GMT -5
Most farmers, and antique pullers are always looking for more power out of their Farmall H-450, here is a few tips to pick up a few HP with out spending alot of money.
First, let's look at the carburator. Zenith, and Marvel Shebler carbs are found on Farmall H-450 tractors, this will work for all models of these carbs.
It would be a good idea to rebuild the carb while you are performing these modifications, a new gasket kit, or a master rebuild kit.
All of the modifications will be done to the carb bowl.
Remove air cleaner tube, and 4 bolts that hold the carb bowl to the throttle body. once removed, remove the main jet adjustment screw, and the brass metering stem located in the center of the bowl. It is usually a 3/8 deep well socket, and a regular screwdriver. Go tot he hard ware store, take the bowl with you, and go to the drill bit section, find the drill bit that fits the main jet perfectly, then find the drill bit, that is 3to4 sizes larger, this is the drill bit needed to make the modfications, Witht he parts removed from the bowl, drill out the main jet, then drill out the bottom 2 holes of the metering stem with the same drill bit. thoughly clean the shavings out of the carb bowl, and reassemble the parts you have removed. Reinstall carb bowl to throttle body, and air cleaner pipe. With the main fuel adjustment installed, turn it about 1.5 turns off the seat to start with. Start engine. The adjustment can be done at full throttle, or on a dyno, at full throttle, (no load) turn out main adjustment until the engine starts to smoke, or run rich. then turn the adjustment in until it smooths out, you are ready to work or play. Will give it a bit more lug, and about 3-5 more HP at 540 on the dyno. Will post more info on performance tips if you like what you read!! Thank you, ChadS. Steininger Performance Antiques, Akron, Indiana
First, let's look at the carburator. Zenith, and Marvel Shebler carbs are found on Farmall H-450 tractors, this will work for all models of these carbs.
It would be a good idea to rebuild the carb while you are performing these modifications, a new gasket kit, or a master rebuild kit.
All of the modifications will be done to the carb bowl.
Remove air cleaner tube, and 4 bolts that hold the carb bowl to the throttle body. once removed, remove the main jet adjustment screw, and the brass metering stem located in the center of the bowl. It is usually a 3/8 deep well socket, and a regular screwdriver. Go tot he hard ware store, take the bowl with you, and go to the drill bit section, find the drill bit that fits the main jet perfectly, then find the drill bit, that is 3to4 sizes larger, this is the drill bit needed to make the modfications, Witht he parts removed from the bowl, drill out the main jet, then drill out the bottom 2 holes of the metering stem with the same drill bit. thoughly clean the shavings out of the carb bowl, and reassemble the parts you have removed. Reinstall carb bowl to throttle body, and air cleaner pipe. With the main fuel adjustment installed, turn it about 1.5 turns off the seat to start with. Start engine. The adjustment can be done at full throttle, or on a dyno, at full throttle, (no load) turn out main adjustment until the engine starts to smoke, or run rich. then turn the adjustment in until it smooths out, you are ready to work or play. Will give it a bit more lug, and about 3-5 more HP at 540 on the dyno. Will post more info on performance tips if you like what you read!! Thank you, ChadS. Steininger Performance Antiques, Akron, Indiana
