It sems to want to run out of fuel and not refill. I can poke on the floats and make it come on, but it seems like it lets the fuel get to low. It drops all the way down to the bottom of the filter. What level should it fill to?
I already checked it up to the float switch. Should it have 50 volts...??..
Those pumps must be built tuff to run 50 volts
These are quirky things. 3 of 3 that I serviced recently would only maintain the fuel at a low 1-1/4 inch level. If they got too low they would shut off. Shutting off when too low makes sense as the pump is drawing air if it is running and not filling the tank so a shut off might keep the pump from running until damaged.
Before you abandon the float switch altogether try this as it worked for me. Empty the tank. Pull the red power lead from the rectifier output on the other side and connect the red lead to 24vdc positive and ground the frame at the ground lug to 24vdc negative. slowly fill the tank and I bet at some point around 1-1/8 to 1-1/4 inches of fuel level it will come on and add some additional fuel before it shuts off again.
3 of 3 I recently worked on did the same thing. I then reconnected the red wire and ran each of the three units for 45 minutes to 1 hour under a 4kw load and the fuel level in the tank was maintained the whole time.
The bosch float incorporates a relay. If you cannot locate the float by the bosch number on the float then try Omega for a substitute float. I saw some in the $35 dollar range that could be used if a relay was added. I suspect the Bosch float is mega dollars.
54 vdc is spec for the Yanmar rectified output. It does seem to drop a bit when the pump places a load on it but it is hard to measure exactly what it is doing when the pump is pulsing. The best I can guess is that it is no less than 30 - 35 vdc.
So far I have been making sure the units I get are serviced to run to spec but I would like to fix a few of these design issues and convert to 12vdc and mount a battery for permanant electric starting.
I really like these little units. They are quite capable.
Search e-bay for the 178 and 186f motors. There are a lot of engine parts and accessories listed.
Doug
