Quote:
Originally Posted by porschesam
The 4 barrels are at the same height now bit the forward plunger is still not dropping low enough to reach the fuel feed ports in the barrel. I've tapped on this plunger several times after rotating the engine/pump. No luck getting this one to move. The other three plungers seem to be dropping down low enough to get fuel but I do pump any fuel to the injectors.
Is it possible a bad diaphragm or vacuum pump could cause a no-start condition?
Could the rack/control rod be stuck in the no fuel position where the plungers would be rotated to not deliver fuel to the injectors?
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No Vacuum causes the Governor to give more Fuel. That means if the Govern Diaphragm had a hole in it you would get more Fuel.
One of the things that happens to the Govern Diaphragm is it gets stiff. A stiff Diaphragm might reduce the Fuel.
If the Pump has not been used for a long time the Rack can indeed stick. Infact If one Plunger sticks and will not rotated it will also hold the Rack in that position.
Did you remove the Side Cover to see if any Springs were Broken. Removing the Side Cover will not harm anything.
If the Plunger at some Point gets stuck in the Barrel you could pull them both out and hopefully the Plunger will stay in the Barrel becuse you need to note which way the Bottom of the Plunger Faces.
The below info is is about Bosch Fuel Injection Pumps I worked on 1975-1980. That would mean that they were actually older Pumps that those years.
There is to sides to the Bottom of the Plunger. One side will have like a Chisel Mark on it and the other side will not. Other than that both sides are the same.
The Chisel Mark has to go back in facing the Same direaction as it came out. It is possible to get the Plunber 180 degress off becaus the Plunger will fit into the Sleeve either way.
Now that I think of it the Plunger is goes up and down in a slot in the Sleeve. If that area of the Sleeve is rusted it can also keep the Plunger from moving up and down correctly.
You might be able to tell of the side Cover is removed (this is the Cover Behind the Fuel Supply/Lift Pump).