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RarlyL8 RarlyL8 is offline
Crotchety Old Bastard
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Join Date: Jan 2000
Location: Huntsville, AL
Posts: 13,550
Tank Screen and Fuel Pump R&R

Fuel filter wasn't the problem. There was a little bit of back pressure when blowing through but not enough to make the pumps work hard.

Next item to look at is the tank screen. This car sat most of it's life and was not maintained as it should have been so I expect to find garbage in the bottom of the fuel lank. If so it could plug up the screen and cause the pumps to draw more current resulting in the hot relays and fuse I am seeing.
This is a very easy job. If you've never done it before don't be afraid of it. It is messy but simple. Put a fan on or have the car in a well ventalated area (for obvoius reasons).

To empty the tank I pulled the fuel inlet line off the front pump and collected in a gas can.

Once empty you unscrew the plug. The plug has a large allen head fitting, you can make a tool using a 7/8 socket and cut off allen wrench.

Collect the rest of the gas in a pan. Not too much comes out.

This is what the screen looked like, some rust but not bad enough to cause the problem.

All cleaned up and ready to re-install.

Put gas back in the tank and fired 'er up. Problem unchanged. Pump still screams after a few minutes and the fuse/relay gets too hot to touch.

Looks like the pump is next to check. This pump is low mileage and not too old so I really didn't think it was the problem. Typically I would blame the 30 year old pump first. Everything needs checked on this old car so the pump is next.

I pulled the fuel feed line off the pump and stuck a large bolt in the rubber line to hold off another gas bath while I changed the pump. Here are the simple hand tools I used, not difficult at all.

Well that made progress, looks like the newer pump went bad. The old pump was installed and did not scream after a few minutes. The fuse got hot but the relay did not. There is still work to do as I don't want anything getting hot. It looks like now we can concentrate on wiring. I may relace this fuse block.

Two steps forward and only one step back. Ha!
RarlyL8 Motorsports / M&K Exhaust - 911/930 Exhaust Systems, Turbos, TiAL, CIS Mods/Rebuilds
'78 911SC Widebody, 930 engine, 915 Tranny, K27, SC Cams, RL8 Headers & GT3 Muffler. 350whp @ 0.75bar
Brian B. (256)536-9977 Service@MKExhaust Brian@RarlyL8

Last edited by RarlyL8; 06-29-2014 at 12:20 PM..
Old 06-29-2014, 12:17 PM
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