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Discussion Starter #21
Ok, so another update, put in new plugs to be safe and cranked a few times. Checked the new plugs and they were dry as a bone. Rather than make a mess at the fuel rail, I decided to check my work. I pulled the neg off the battery, removed + and - to the in tank pump and again applied 12v to the tank pump and it came to life as usual. I then double checked the main pump in the same way and got absolutely nothing. When i did this initially, the in tank pump was still plugged in. when the power was applied to the terminals of the main, if fed power to the tank pump and my noob ears mistook that the main was running. When i removed all wires from the main and applied 12v I got absolutely nothing. So I made an initial diagnosis error. I have a pump and filter on order now and can't wait to get it done. I can't believe that a 2 year old main pump failed after 5-600 miles.

How much pressure do you think has built in the incoming fuel line to the main pump with all that cranking. Will that dissipate or will that pressure remain. I'm trying to see if in need to be prepared for a big clean up! The main pump replacement seems pretty straight forward. I'll do some research hear and will also take any suggestions/ tips. And again if you want to see photos, they are still posted on the auction page here =1986 Alfa Romeo Spider Graduate

thanks
 

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Fuel pressure will have disappeared by time the new parts arrive.
The fuel pressure regulator allows any excess fuel back to the tank.
No worries?
 

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Will be Fine don’t worry
You always get a few drips of fuel but it’s not going to drown you ?
 

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Main pump and filter replacement are very easy. No mystery here, just remember to reconnect the leads correctly.
 

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Discussion Starter #26
Success! If only my initial diagnosis of the main pump was correct, I'd be driving days earlier! Switched out the generic pump for an OE Bosch and the car roared to life. The original relay works perfect. No leaks, all is well! Thanks again for all the help everyone! If your in NJ, I'll see you on the road!
 

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Congrats on getting it running.
I am recently having a similar issue. Can you hear the in tank pump humming? I recently had a no start issue. The main pump wasn't humming even when applying power. So I just put a cheap main pump in and now it hums I also put new plugs, wires, cap, rotor, upper, lower, and bypass coolant hoses, and radiator fan in. Now the new main pump hums on turning the key on. But it will crank and crank if I turn the key off and on several times it will sometimes fire and stay running. And it runs fine. But I think my in tank pump isn't working at all. And when I test for power at the main pump one wire has 8.4 volts. I jumped positive from the battery and still didn't hear a hum.
 

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Discussion Starter #29 (Edited)
Congrats on getting it running.
I am recently having a similar issue. Can you hear the in tank pump humming? I recently had a no start issue. The main pump wasn't humming even when applying power. So I just put a cheap main pump in and now it hums I also put new plugs, wires, cap, rotor, upper, lower, and bypass coolant hoses, and radiator fan in. Now the new main pump hums on turning the key on. But it will crank and crank if I turn the key off and on several times it will sometimes fire and stay running. And it runs fine. But I think my in tank pump isn't working at all. And when I test for power at the main pump one wire has 8.4 volts. I jumped positive from the battery and still didn't hear a hum.

My tank pump is loud when the car is off. Go back to the tank and unplug the pos and neg at the pump and apply a separate 12v source to those terminals. Mine is loud enough to know its on. I think the car definitely needs both. My tank pump was humming and no fuel was getting past my dead main at all.
 

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My tank pump is loud when the car is off. Go back to the tank and unplug the pos and neg at the pump and apply a separate 12v source to those terminals. Mine is loud enough to know its on. I think the car defiantly needs both. My tank pump was humming and no fuel was getting past my dead main at all.
I think my tank pump is also shot I will run positive and negative from battery tomorrow. This would make sense why the new inline pump is loud. It's sucking air and fuel. And as soon as I get enough fuel from the tank it runs fine.
I will update tomorrow.
 
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