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Engine Specific Info and Questions => IDI Engine => Topic started by: farkman on August 18, 2004, 11:56:25 am

Title: A little problem
Post by: farkman on August 18, 2004, 11:56:25 am
I installed my new Fleetguard fuel filter yesterday in my car. Today when I went to look at it, the hose from the filter to the injection pump is nearly empty. I filled up the fuel line with fuel and started the car. There were some air bubbles at first but nearly all went away in about 5 minutes. I let the car sit for about an hour and went out to check it again. Same thing, the fuel line is nearly empty. There aren't any fuel leaks either. I'm wondering if the return line might have something to do with the problem? It goes straight back to the tank instead of the stock way, to the filter and then the tank. Also, does it matter if the lowest point in the inlet fuel line is below the inlet port in the injection pump. If I can't fix the problem I guess I'll go back to the original filter :evil:. If anyone has an idea as to what could be the problem I'd really appreciate it.

Peter
Title: A little problem
Post by: QuickTD on August 18, 2004, 06:11:19 pm
Is the car difficult to start? If not, I wouldn't worry about it. I've never removed a fuel filter that has been completely full of fuel. There is always air in the top and in the line. I used to sweat it too, then I read an explanation of this phenomenon. Here it is... http://www.baldwinfilters.com/engineer/pdf/94-6r.pdf
Title: A little problem
Post by: farkman on August 18, 2004, 06:54:54 pm
Thanks for your response QuickTD  :D.

The car wasn't difficult to start but it did run rough since there was so much air in the lines. And there wasn't just a little air in the line, more than 75% of the line was air, which is why the car ran rough. But when the car was running the line was filled with fuel and an hour later most of it was gone (like vacuum sucked it back into the filter, or something).

The question I have is why wouldn't the stock fuel filter do the same thing. The fuel line was always full with the stock filter. I was wondering if it would be okay to do a dual filter setup. Putting the Fleetguard filter before the stock filter so the only filter that gets dirty is the Fleetguard and the stock filter still retains the tee fitting on the return line. As for the little tee on the stock filter, doesn't that also fill the filter with fuel and  once the filter is full then the excess goes back to the tank.

I put the stock filter back for now, because I need the car and I don't want to drive a car that could leave me stranded. Plus I need to go get some diesel because I've been filling the filters with diesel additive. I used about $6-8 worth of additive just to fill up the Fleetguard filter :lol:.

Thanks

Peter
Title: A little problem
Post by: QuickTD on August 18, 2004, 09:33:28 pm
Quote
As for the little tee on the stock filter, doesn't that also fill the filter with fuel and once the filter is full then the excess goes back to the tank.



Nope, the tee is only open to the filter when the fuel temperature is below a certain point, 5ºC rings a bell, but don't quote me. There is a bimetallic "thermodisc" in the tee that snaps the valve open and closed, it is not variable.