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Hi All,
I have an F75 in a 1992 fourtrak (rocky) and it has develped a confusing problem. Shortly after changing the fuel filter it has started to run for about 2 secs and then stop on startup if you catch my drift.
It seems as if there is air in the fuel line but there is good pressure all thorugh it and if you undo the banjo at the engine end of the fuel line (at the injector pump?) you certainly get a good spray of fuel out.
Now I know you are all going to say that it is air, but I have cranked, pumped and started this thing at least 20 times and it is no different.
When I undo the fuel lines at the injectors I get fuel dribbling out rather than spurting so I suppose it must be some sort of pump problem - am I correct?
If so, where do I look next? are there two pumps - the lift pump and the injection pump? If so, where do I find the lift one? could it be that it is blocked at all?
HELP!
Thanks
NID
There could be a
There could be a manufacturing falt in the new filter. Not likely to couse bad flow, but possible. Easy to check, put the old one back on, replace it again or by pass it altogether (temperarily of course).
There is a second filter (or there was on the early modles) in the pump it self. It's just a gauze really, hiden in insid the inlet pipe. Unbolt the fule line from the pump and have a look. This may well be partially blocked, especially as you have been disterbing the fule system.
The lift pump and injecter pump are all part of the same unit. It is posible the lift part of the pump is not opperating at best efficiency. This can be checked by plumbing a temporary electric fule pump in as close befor the proper pump as posible. If the electric pump solves the problem then you need too get inside the pump. That said a friend of mine drove his with this tempory fix in place for over a year, and sold the car like it.
Check the metal parts of the fule line, there may be a semi squashed section restricting flow. There could even be a flexi section which has become twisted or snaged or traped somewhere. Again especially as, but not exclusivly becouse, you have been working on the system.
Also if a section of the fule line is starting to breack down inside (this can be the case even if the outside looks fine), then a partical or 2 which have brocken free may be wedged somewhere (even in your new shiny filter). This breacking down could also cause the pipe to lose its integral strength, and let it be sucked flat by the pump.
Can't think of anything els at the mo...
Any veiws expresed in this thread by me are purely from my own experience, and (sometimes) falible memory. Hope my comments help, but please don't take them as gospel.