Fuel Pump won't shut off.

[Alan Dykes]

Hey guys,

I have a 2005 Mercruiser 350 Mag. Model 4442077TS, Serial 0W065360. When I turn the battery switch on, even with the ignition switch off, the fuel pump starts running and will not shut off. Is there a relay or something that could be the problem, or am I looking at a new pump?

Thanks,
Alan

 

[achris]

Re: Fuel Pump won't shut off.

Sounds like a stuck relay. Or the ECU is holding it closed. You have 2 relays, swap them and see if the problem stops. If not, you are going to have to go digging with a multimeter....

 

[Alan Dykes]

Re: Fuel Pump won't shut off.

Thanks. I will try that tomorrow. Is it possible that it isn't building enough pressure to shut it off? What should the pressure be?

 

[Don S]

Re: Fuel Pump won't shut off.

Building enough pressure is not the problem and has nothing to do with it. It shouldn't be running at all until you turn the key to run, and then only for 2 seconds.

 

[Fun Times]

Re: Fuel Pump won't shut off.

Is it possible that it isn't building enough pressure to shut it off? What should the pressure be?

No the system does not work like that, it should turn off with or without fuel pressure at key up. Your fuel pressure should be within 42 psi.

 

[Alan Dykes]

Re: Fuel Pump won't shut off.

Ok. Thanks. I thought it may run until it builds up pressure.

Thanks again,
Alan

 

[Alan Dykes]

Re: Fuel Pump won't shut off.

I switched the relays and it does as it should. I switched them back and it is still fine. Should I go ahead and replace them, or should they be fine now after getting bumped around?

 

[achris]

Re: Fuel Pump won't shut off.

Indicates sticky/burnt contacts... Personally, I'd replace both. I would also find the original manufacturer of the relay, not buy it through Merc. They have a 200% mark-up. I did look for them at one stage a few months back and found a source in USA, but shipping to Australia made it prohibitive... I can chase it up again if you like... Merc want $27 a piece. I remember I found a website selling them for about $10 each. It was the SAME relay, not a Chinese copy....

 

[Alan Dykes]

Re: Fuel Pump won't shut off.

That's what I was thinking. If you run across that info, it would be great. I'll try to track them down myself.

I appreciate the help,

Alan

 

[achris]

Re: Fuel Pump won't shut off.

I've started looking them up.. Here's one I found on e-bay, but I think I can find some even cheaper...

(BTW, it's a 'Hella 12193611')

2005 Kawasaki KVF750 4x4 Relay 12193611 | eBay

Found this on Amazon, only $5 each
http://www.amazon.com/Omron-G8W-1C6...68665704&sr=1-2-fkmr1&keywords=hella+12193611

Worth buying 6, sending 2 to me, and you have a couple of spares

Chris........
(I'll keep adding to this post rather than making a new post each time....)

 

[Alan Dykes]

Re: Fuel Pump won't shut off.

Thanks. I found Sierra part number 18-5851 for around $15 too.

 

[achris]

Re: Fuel Pump won't shut off.

Thanks. I found Sierra part number 18-5851 for around $15 too.

Be careful with the Sierra stuff. A lot of it IS cheap crappy Chinese rubbish....

 

[Alan Dykes]

Re: Fuel Pump won't shut off.

Well, I bought new relays thinking that I had solved my problem. I can hear the relay click now when I turn the switch on, but now the pump doesn't run. What voltage should be at the connector at the pump? 12v? If I have 12 volts there, does that mean my pumps are bad? If so, which one? There are two, low and high pressure.
Thanks,
Alan

 

[Alan Dykes]

Re: Fuel Pump won't shut off.

In addition, the pump will run every once in a while. Maybe one time out of 50.

 

[achris]

Re: Fuel Pump won't shut off.

You had one good relay from the original pair. Use that the try and find out what's going on. (If the new relays are cheap Chinese, then you could easily have a bad one, or both)...

Chris.....

 

[Alan Dykes]

Re: Fuel Pump won't shut off.

So, since the pumps work occaisionally, is that a good indication that the pumps are fine and there is a different problem?

 

[achris]

Re: Fuel Pump won't shut off.

Possibly

 

[Bt Doctur]

I guess its the same as the Blazer fuel pump relay socket

 

[Bt Doctur]

available at most junk yards, system relay is rated 30 amps (I think) Bosch 12077864 800

 

[Fun Times]

Hi Guys, I know this is an old thread, but figured it was worth a try. Do any of you happen to know the part name or number that the actual relay plugs in to? This would be the female portion hard wired to the wiring harness. I found that one of the connectors in that female part was fried, so I'll need to replace it. This issue caused my fuel pump to stop running under control of the ignition. I'll post a pic as well. I appreciate any help y'all can provide!

An auto parts store or a GM dealer should be able to find one using the Delphi >66< number you see on the back or I believe the one in the following link will work as well. Comparing the two images from your photo and the first link below, it looks like the 280 mini relay connectors will match up,
http://www.delcity.net/store/Hella-I...ctors/p_808969
https://www.waytekwire.com/item/422/...-Tool-/​

logan87306, In the future, please create a new topic of your own vs bring up an archived topic such as this. Should the older topic be related, then just add a link to it in your new topic and use it as a reference....It helps keep overall confusion down of who to help try and answer. I'll create you a new topic for you using these 4 new posts.

Thanks!
iboats mod team.