Walbro In Tank Pump

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Hefeweizen
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Walbro In Tank Pump

Post by Hefeweizen »

So I finally installed the Walbro In-Tank Fuel Pump. Kind of loud but the biggest problem is that the fuel pump relay keeps blowing. Anyone have a similar experience? It does get expensive if I have to replace the relay after every time I was driving the project car. I had to reduce the high pressure hose since the tank outlet requires 1/2 inch inside diameter and the steel fuel line is about 1/4 inch but that should not matter. :-k
Rainer
03 330Xi (DD)
85 635CSi (RIP 3 May 19)
80 633CSi (Red Euro, Project)

"If you think a good European mechanic is expensive, try a bad one!"
baders
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Re: Walbro In Tank Pump

Post by baders »

Odd that you are "blowing a relay" and not the fuse ? What is the relay rated to (current) ? What current draw is the Walbro pump ? Also, you should check your fuel pump fuse for correct rating.
1986 635csi LOCUTUS / Arktis Blau Metallic / Pearl Beige / S38B36/ Close ratio dogleg 5sp
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Hefeweizen
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Re: Walbro In Tank Pump

Post by Hefeweizen »

The relay was rated 30 Amps. I don't know what the draw of the pump is, it does not say. The fuse is 25 amps.
Rainer
03 330Xi (DD)
85 635CSi (RIP 3 May 19)
80 633CSi (Red Euro, Project)

"If you think a good European mechanic is expensive, try a bad one!"
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Hefeweizen
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Re: Walbro In Tank Pump

Post by Hefeweizen »

So I am afraid I have to take everything back. Turns out the relay is not blown. Glad I am not that fast in throwing things away. Just for giggles, I put the relays into my DD and the car started right up. Took the relay out and put it in my 633 and it started up also. Have to figure out now what the deal is. What really makes me wonder is that I can drive the car without any problems, park it and then later when I want to start it, it will not start. When I check the fuel pump, I do not get any power to it (built an extension cord for my voltmeter so I can sit inside the car and crank). Apparently when I take out the relay and put a different one in, the car starts or at least gets voltage to the pump ](*,)
Rainer
03 330Xi (DD)
85 635CSi (RIP 3 May 19)
80 633CSi (Red Euro, Project)

"If you think a good European mechanic is expensive, try a bad one!"
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Hefeweizen
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Joined: Thu Jul 17, 2008 1:24 pm
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Re: Walbro In Tank Pump

Post by Hefeweizen »

Alright, I think I got the problem figured out. If it is not the multi plug to the fuse box, it is the flap in the AFM being stuck in the closed position. If I put a screw driver in and open the flap, the pump starts going. Once that has happened the car runs fine.
Rainer
03 330Xi (DD)
85 635CSi (RIP 3 May 19)
80 633CSi (Red Euro, Project)

"If you think a good European mechanic is expensive, try a bad one!"
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