i am going to do the fuel filter for the bosch system on an '89 740 gl. i have the proper tools and read over the procedure in the faq section. how much time should it take? i am short on time but i wanted to do it before i take it out of town.

benjamin
--
1989 740 GL

As others have said, leave it for a better time; plan a full evening if you are removing the original filter. Remove the entire assembly from under the car, and you don't need no stinkin' impact tools... ;) If the hard plastic line that connects the pump and filter breaks remove it all and use fuel-injection grade hose and a couple stainless clamps.
After 16 years my original filter was functionally perfectly serviceable; I changed it because it was starting to rust so badly that fuel seeped through it.

Shifted
--
'87 745t 210,000; '93 Toyota MkII; '73 Suzuki Jimny 360

I agree with Art, leave it alone, especially if you are going on a trip and time is short. There are several things that can go wrong and you will be stuck. The filter is massive and does not clog. I have never heard of a performance, no start, or any other problem being solved by replacing the filter, they just never give trouble. If the filter is going to clog it will be a very very gradual process and will give plenty of warning such as power loss when high fuel flow is needed such as when you floor it or climb a mountain, it cannot suddenly clog up and strand you. I have actually read here of Bricksters changing the filter in misguided attempts to solve idle problems. I do not consider filter replacement a preventive measure, there are many more important preventive things to do.

A quick easy diagnostic check for good fuel flow is to start the pumps with the tank return line removed at the fuel pressure regulator and allow fuel to flow into a container, there should be a large unrestricted flow from the return line. When car is running only a very small fraction of that flow is actually consumed by the engine through the injectors.
--
David Hunter

proper tools? 15 min. +2 min for the lift to rise and fall and a minute to recycle the fuel, 5min for paperwork. 10 min test drive and 5 on telephone leaving msg for customer.

Opinion:

Unless you have clogged fuel filter symptoms (struggling up hills) or it is leaking from rust pinholes, I'd put it off until you have no deadline to meet. There are many things that could happen to leave your car in need of a run for costly parts, especially if you don't have impact tools.

Once you've done one, then the amount of time can be predicted.

Don't mean to sound discouraging, but changing a fuel filter on a maintenance schedule or "just because" won't make your travel any more reliable. That filter is plenty large enough to hold 15 years of whatever if you're using busy filling stations and keeping fuel level decent.

--
Art Benstein near Baltimore

i was not planning on using impact tools but if it would be easier for the banjo bolts i will go ahead and do it. i was planning on doing it as a matter of maintenance. but also the vehicle sat for a year and a half with the same gas in it and not being run. i flushed a half tank of clean gas through it.
she runs as fine as can be expected.

benjamin
--
1989 740 GL

If you have them, I would definetly use impact tools. I did not the last time I changed the filter, and ended up tearing the filter and ofcourse having to buy a new one. Metal gasoline fittings are hard to make tight, especially if you cannot get good leverage. If I would have done it the right way, it would have taken me about 20 minutes from start to finnish. The way I did it, it took me close to one hour.