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Hi Folks-I need your guidance please-I am new at this. Working on a standby Diesel Generac. Replaced the Stanadyne Model 80 Filter and assembly, re-attached all the hoses etc. and now the unit won't fire. I can't find the procedure on how to bleed/prime the filter...Is that required...Can anyone shed light on where I am going wrong.? Appreciate any help with steering me in the right direction. t:confused:
Welcome aboard!
I think we can help. The 80 is simple. It has 2 external valves. The top valve is the bleed, the bottom is the water drain. If the filter is correctly oriented, the top valve will be located on the short side, with a nipple below it (to direct fuel away during bleeding). The bottom valve will be at the lower corner of the long side, with a nipple exiting from the bottom (around the corner from the valve, for water/fuel draining). Opening both valves will allow fuel to drain from the filter, making it less messy during filter removal.
Make sure the valves (plastic "stars" with a threaded shaft) have good O-rings, and they are tightly closed (hand tight). If you have an electric fuel pump, activate it (without cranking the engine, most generators have a "prime" circuit, if not, apply system voltage to the pump) and open the top bleed valve. Once the filter is full of fuel (fuel will flow from the top nipple), close the bleed and allow the fuel pump to run while you loosen a fuel line connector as close to the injection pump as possible. With all connections and valves closed, check for leaks. Once the air is bled and fuel system is pressurized, attempt to start. You'll have to push out all the air you forced in while trying to start with a dry filter. If you were unable to bleed between the filter and injection pump, it will take more cranking to push the air through, but it will go.
If it has a mechanical lift pump, disengage the injection pump (manually, or disconnect the power lead), and crank the engine while the injection pump fuel inlet line is loose. Once fuel flows there, tighten the line, reconnect the IP supply power, and attempt to start. Fully charged battery(ies) will be very helpful.
In the future, don't try to start until the fuel filter is bled. If done correctly, you should only have to bled the filter, and the little bit of air that enters the outlet line will be minimal, and should cause no more than a very short "hic-up" during the first start. If this generator does not have a "prime" feature, it would be very helpful (and simple) to add one.
Oh I appreciate your help on my situation-thank you. I will give that a try and report back on what I find...Very helpful info!!