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How to bleed engine fuel filters

wenders

New member
This sounds like a dumb question, but humor me because I am new at this.There are 2 fuel filters on the side of my Lehman 135 engine. I replaced the cartridges , but now it's full of air and I don't see a way to bleed it. Any suggestions?
 
Hi, there are two bleed screws (bolts) off center of the filter retaining bolts fore and aft on top of the filter assy. Loosen both and use the hand primer on the lift pump. If fuel is not being pumped than rotate the engine until resistance is felt on the primer lever.
Charlie w.
 
Thanks, Charlie. I figuered one of the 2 screws must be a bleed screw. I will now go and see if I can locate the lift pump.
 
I used the liftpump, but found it to be quite inefficient, specially when there is a lot of air to be replaced. There must be a better way, like some kind of electrical pump. Thanks again for your helpful advice, Charlie.
 
Hi wenders, if the pump is on the high side of the camshaft the diaphram is compressed and little or no fuel will pump. Try turning the engine using a 15/16 long handle wrench on the front of the crankshaft 1/4 of a turn at a time until you get a good fuel flow. It may take several turns. Or if you have an oil removal hand pump,take out the bleed screw and hold the suction side of the pump to the bleed screw hole. This usually works very well if the pump has a rubber base. An electric pump can rupture the diaphram and fill the crankcase with fuel .charlie w.
 
Ok, I will try this next. What do you think of using something like a turkey baster to force fuel into the top of the second filter until air and fuel comes out of the top of the first filter?
 
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