1982 spider Fuel Pump Relay Issue

scagliog · #1 (**permalink**) 09-23-2009, 08:52 AM

Hello,

I am starting this new thread since I have isolated the non-starting problem of my spider to the fuel-pump.

Yet, I do not know if the pump is fault or the fuel pump relay is.

When cranking the battery delivers around 10.5~11

When cranking and main fuel pump is connected, I see 7 volts at the pump.

When cranking and the main fuel pump is disconnected, I see 0 volts at the terminals.

I hear the relay clicking when I put the key to start or crank. I opened the relay, and it seems to be clicking and closing...

How do I really know if the relay is bad?

Since I found one for $80, I want to make sure that it is indeed the problem...

Thank you,
Giuseppe

**papajam** · #2 (**permalink**) 09-23-2009, 09:38 AM

Assuming good grounds at the pump and voltmeter, 7V at the pump while cranking is not sufficient and zero volts with the pump disconnected has me scratching my head. I would check voltage at relay terminal #30 (input) while at rest and during cranking. If not battery voltage under both conditions, check for loose/corroded connection from the battery (to include the inline fuse and fuse holder).
If voltage is okay, do the same tests on relay output terminal #87. If low voltage on cranking, replace the relay.
If voltage is okay, check the connections and voltages at the inertia switch (firewall, rightside) and pin #9 (pink/white wire) on multiwire connector G73 (behind fusebox).
Have you powered the pump directly to see if it works?

scagliog · #3 (**permalink**) 09-23-2009, 10:55 AM

Hi Jim,

I was going to power up the pump directly next...

Now, as far as checking the terminal voltages, I assume I removed the relay and probe the holes???
Voltmeter connected to the terminal and ground?

I have an Alfa manual which also says to check the voltage at terminals #30 and #87. I did that removing the relay and probing across. In that case I read the battery voltage (12.3) in any condition.

I suspect that I have to probe the terminals separately...

Thanks a lot!
Giuseppe

**papajam** · #4 (**permalink**) 09-23-2009, 12:20 PM

Well, since there is 10.5-11 cranking volts but only 7V at the fuelpump, there would appear to be a voltage drop somewhere in the circuit. Since most voltage drops occur only under load, the relay and the pump need to be hooked up.
Perform the tests with the voltmeter black lead to ground and the red lead to the appropriate terminal.

scagliog · #5 (**permalink**) 09-23-2009, 12:53 PM

Hi Jim
thanks will do the test when I get home from work.

Hook everything back up, and test the terminals at the relay.

Giuseppe

**ghnl** · #6 (**permalink**) 09-23-2009, 07:28 PM

If the relay is OK, a Voltage Drop Test should tell you where the problem lies. Here's a page my brother wrote about Voltage Drop Testing.

scagliog · #7 (**permalink**) 09-23-2009, 10:32 PM

Ok I have 12.5 volts at the fuel pump, and it is not moving. Can I conclude that the fuel pump went bad, and that it is causing the voltage drop (from 11 to 7), since it is not turning....

now, any hints to where to order a fuel pump...even used...

thank you
G

scagliog · #8 (**permalink**) 09-23-2009, 10:39 PM

I found a few at Kragen auto parts...

For vehicle: 1982 Alfa Romeo Spider Veloce L4 2.0 Liter L4 2.0 Liter FI
While we find your parts, please enter your ZIP Code at CSK Auto

From $189 to $326

anybody has bad experiences with the cheap ones...

G

**ghnl** · #9 (**permalink**) 09-24-2009, 07:22 PM

IAP has a Bosch fuel pump for $269 - item #90103.

Also, see the note in their Tech Bulletin.

scagliog · #10 (**permalink**) 10-04-2009, 09:12 PM

Want to close this thread. It was indeed a bad fuel pump. Interestingly enough, the pump turns, or at least makes noise like it is working when powered, yet, NOTHING coming out of it. I replaced it with a $189 that I found at Kragen. 1 year warranty. Seems to work fine. It just needed some adjusting of the fuel lines to fit, since little longer.

Thanks everybody for the help