more Rochester Issues
06-16-2010 | 07:27 AM
#21
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From: Centereach, NY
Fuel Pump is 2 weeks old...if i unplug the line from the carb and disconnect the distributor and turn the motor over i get fuel shooting 15 feet lol i think the pump is in good working condition...i will check the valve again but cleaned it to start the season.
06-16-2010 | 07:45 PM
#22
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From: West Suffield
Hey,
Sounds like the top butterfly is not opening. Was the boat running ok then just nosed over about the time the secondaries should kick in?
looking at the front of the carb there is a rod on the top left side that connects to the choke pull off diaphragm. Make sure that linkage operates freely, and is not bent.
hope its simple.
Sounds like the top butterfly is not opening. Was the boat running ok then just nosed over about the time the secondaries should kick in?
looking at the front of the carb there is a rod on the top left side that connects to the choke pull off diaphragm. Make sure that linkage operates freely, and is not bent.
hope its simple.
06-17-2010 | 05:44 PM
#23
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From: Centereach, NY
idk i tried driving and looking and i looked back when i hit the gas it opened about a quarter but also bogged down i don't know if the engines rpm opens it up and that fact that its bogging is the reason it doesn't have the pull to open further. ill keep searching for my answer thanks guys
06-17-2010 | 06:03 PM
#24
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From: Aurora Ontario
OK, directly underneath the vent tube on the float bowl is the power piston. When you open the throttle and engine vacum decreases, a small coil spring lifts the power piston and front metering rods. With the motor off, you need to insert a small pocket screwdriver sized object down into the tube and let it rest on the top of the piston. Then very gently, see if you can push down about 1/4" and then have the piston lift spring push the screw driver back up.
The piston should move up and down very freely. If its stuck, and I have seen it hundreds of times, you will go lean as heck on the front two barrels and never make any power.
As for the secondary air valve, air flow being drawn into the motor thru the secondary ( rear ) throttle plates pulls the air valve plate open against a very weak spring pressure. As the air valve shaft rotates open, it operates an internal cam which lifts the secondary meetering rod holder and thusly, the metering rods out of the secondary main jets allowing more fuel at full power. If the motor is not drawing in the air, the plate will not open fully.
The secondary throttle shaft lock out cam is behind the choke mechanism. It is there to stop the secondaries from opening on a fully cold engine. Make sure it is not seized part way off and stopping the secondaries from opening.
The piston should move up and down very freely. If its stuck, and I have seen it hundreds of times, you will go lean as heck on the front two barrels and never make any power.
As for the secondary air valve, air flow being drawn into the motor thru the secondary ( rear ) throttle plates pulls the air valve plate open against a very weak spring pressure. As the air valve shaft rotates open, it operates an internal cam which lifts the secondary meetering rod holder and thusly, the metering rods out of the secondary main jets allowing more fuel at full power. If the motor is not drawing in the air, the plate will not open fully.
The secondary throttle shaft lock out cam is behind the choke mechanism. It is there to stop the secondaries from opening on a fully cold engine. Make sure it is not seized part way off and stopping the secondaries from opening.
