I am having some IP issues on a pump for which I have no replacement. It appears that the feed pump inside the pump is all but nonfunctional. It will hardly run off idle unless the primer bulb (from an outboard fuel tank) is pumped. This thing is a new to me basket of problems. Hopefully all others are corrected. It has no fuel coming out of the return line while its running and it does not appear to be a seal(ing) issue since it will hold ~20 inHg on the pump inlet, and performs exactly the same drawing fuel out of a jar right next to the pump.
I have never been inside a Bosch IP since I have always had more good ones than I needed. Lots of seal and O ring replacements, but never past the top cover.
I am in need of some diagrams of the internals and any info on disassembling them. Is any of that stuff posted here? Does anybody know where I might find this kind of info?
TIA
Jason
Replacing the pump is not likely an option since it is a Volvo. (Audi+1, Rabbit+2)
try to run a exterior pump to feed from the tank,and see if its better.
Sounds like stuck vanes on the low pressure side of the pump to me. Pump pics posted here someplace. Maybe in the FAQ section if not on net. Look for Bosh VE pump and see what you get. Oh click on images on the left side to just show you the exploded views you may need. Rebuild is not that hard we do em all the time. Just that sometimes they don't run any better. At first.
try to run a exterior pump to feed from the tank,and see if its better.
Take out the return orifice bolt and clean it with brake clean. The tiny orifice is clogged per your symptoms.
You should be able to blow into the bolt while submerged in water with a lot of bubbles out of the orifice. Do that first before cleaning to confirm that it is clogged (i.e. no bubbles)