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So I'm preparing to change my fuel filter for the first time since I have owned the car, and I have pulled the fuse for the fuel pump and started her up to relive the pressure, but she never stalls. I even tried pulling both the main pump fuse, and the intank pump fuse, which didn't do much because I could hear that one of them was still running.
Am I going about this wrong? How long does it take for the car to stall?
Thanks for any help,
Justin
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Yeah, I think I may be a little over my head, but what doesn't kill me will only make me stronger : )
I went ahead and disconnected the pump from the line going to the tank and stopped it up with a rachet extension, which works awesome.
I am having the worst trouble in the world with the banjo fittings though. But I think I found the original problem. I suspect the filter is fine, but instead, when it was changed last, they kinked the short line between the filter and the pump while tightening it. It's got a nice crook in it. Luckily I ordered the line when I ordered the filter.
I got pretty frustrated trying to get the fitting off that I stopped and am taking a break to sit back and reassess the situation. My wrenches only go up to 19 mm, and I have the wrench for the oil drain plug.
Anyways, what size wrench do I need to stabilize the filter with on either end? I know the banjo fitting is 19mm, and I'm not too thrilled to use an adjustable wrench on anything. The filter looks like it might be 22mm or so. I'm going out to purchase some wrenches and more rags.
Any help is greatly appreciated,
Justin
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Vice-grips work great to hold the filter. But I got pissed off last time around and used an impact wrench to zip down the fuel filter connection to the pump.
--
'93 244: 'A' cam 4 deg. advanced, 25/22 sways, custom heim endlinks, poly bushings, and a lot more styling customization than I care to recount.
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Yeah, who ever did it last time on my 240 used an impact wrench or some other air tool to tighten it. What a nightmare. I finally got it all off and down from the car, I don't even want deal with it today, I'll knock it out tomorrow morning when it's much cooler : ) There should be a huge warning somewhere on the BB that says, "Do not attempt without an impact wrench or incredible strength and a lift."
Thanks for all of the help, you guys are awesome
Justin
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posted by
someone claiming to be art
on
Tue Jul 15 05:51 CST 2008 [ RELATED]
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Hi Justin,
I sense you're headed for trouble. The fuel filter can be a difficult job without the right tools, and as big as it is, I wouldn't change one unless it had fuel filter symptoms (starving on uphill climbs) or it was rusted to the point of nearly leaking. Do you really need to change it?
If you're committed, I recommend the "quick" method of pressure relief - just have a rag handy, and a pan underneath it all, and be ready to stop up the hose from the tank -- I've used a 3/8" extension rather than a hose pinching clamp. Because there's no accumulator in LH cars, you won't have more than a tablespoon of fuel due to the pressure (stored behind the fuel pressure regulator diaphragm), so the rag (at the rail) barely gets wet.
The mythology behind the Probst quotes, is "Neat" doesn't work on a Volvo because there are no fuses that only interrupt the fuel pump. You could pull the pump's connector loose, under the rear seat, but even that method only runs the motor until the mixture is too lean to support it - still pressure remains.
The "Fancy" relieves only some of the pressure, leaving about 33 pounds instead of 43 at atmospheric (theoretical limit is 14 lbs reduction). Makes you feel as though you've done something. If you have LH2.4, you could dump the pressure by using the test mode to operate the service injectors, but that just puts the gas into the cylinders instead of on your rag, and without a gauge connected, how would you know when to quit?
Anyway, if I've mistaken your need to change the filter, just be aware it is not as simple as the old carb cars. You can destroy lines and fittings in a slip of the wrench.
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You can ignore any other supposed tricks.
IMO, even drawing a vacuum at the FPRegulator is only marginally effective.
Use wrenches as in Art Benstein's photo below, with rags handy to stifle the short spray.
[Pull the 25 amp fuse and the car wont even start (Ignition AND Fuel systems dead).]
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What do you guys think about removing the 25a fuse in the compartment?
I did this and cranked here a few times with the filler cap off. I'm going to put a rag over one of the fitting there and crack it open slowly anyways, but I hope this did the trick.
And be oh so careful with that fuse holder, I accidentally let it slip and hit a ground point. I got the 4th of July all over again. Thankfully the holder is still in tact and nothing caught fire. : )
Justin
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Justin, Not enough pressure to really car about. Just crack one of the banjo Bolts a bit and let it drip.
--
'75 Jeep CJ5 345Hp ChevyPwrd, two motorcycles, '85 Pickup: The '89 Volvo is the newest vehicle I own. it wasn't Volvos safety , it was Longevity that sold me http://home.no.net/ebrox/Tony's%20cars.htm
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I don't know why it doesn't work. I've never tried it that way (pulling the fuse).
In "Bosch Fuel Injection & Engine Management," by Charles O. Probst, SAE, published by Bentley:
"Relieving Fuel Pressure
Neat: pull the fuel pump fuse, then crank/run the engine until it dies,
Quick: wrap the fuel fitting in a shop cloth and loosen it,...
Fancy: connect a hand vacuum-pump at the pressure regulator; when you pump vacuum, the regulator will dump pressure to the fuel tank."
Plus remember to remove the fuel tank cap.
Bob
--
1986 Volvo 245
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Unfortunately, that pull the fuse and run it till it stalls to relieve the pressure is a myth. If you pull the right fuses the car stops right away and the pressure is preserved.
The clean way to do it is by applying vacuum to the fuel pressure regulator to equalize the pressure in the system. The quickie way is to undo the fitting at the rail and let it squirt out into a rag.
Good luck!
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