The infamous 15528707 fuel pump relay.

CapnDirk · September 20, 2016, 12:57 PM

This is more of a seed than anything to help out others.
Drove motorhome 100 miles home after purchase, tried starting a few days later and poured gas on the ground. Replaced hose at filter and electric fuel pump on rail behind battery box (not stock pump). Tried to start, blew another hose, and replaced all hoses in that area. No fuel to carb. Discovered stock pump in tank dead, Bit large caliber bullet and decided to replace tank pump and all hoses (imagine trying to change a partially full hot water tank laying sideways in your houses crawl space). Now I'm going to have gas! Not. On to the fuel pump relay (yes I did check the pump operation prior to re-loading the tank)

This relay is prone to failure and not available. Checked power in on 5 second delay cranking circuit... good, checked power in from oil pressure switch for run latch... good. Neither sent anything out the fuel pump leg. Jumper power to area of relay that would send power to the fuel pump.. nothing out Huh? Decided to open relay...

You can see that the circuit trace AND solder blew like a fuse likely from the load of the frozen pump. Way to go GM, no fuse on the pump?

tmsnyder · September 21, 2016, 10:28 PM

Nice find and fix!

CapnDirk · September 21, 2016, 10:56 PM

Thanks, too bad so many went into the garbage. I read my self half blind on why the fuel pump would not work, and so many people due to lack of availability rewired for something like a 4 prong headlight relay and a momentary switch to prime. This necessitated cutting off the original 5 pin straight plug. A lot of work.

I'm toying with putting in an inline fuse on the pump line, would rather replace a fuse than a relay. I would like to see someone else open up a failed one to see if this was the problem that caused the part to have a high failure rate. Since they are all machine made, it could be. It was not the failure of a component on the circuit board but the copper trace and solder.

Robear · September 23, 2016, 09:48 PM

I have a 86 winnie c30 chieftain. I suspect the fuel relay switch is bad, but for the life of me I cannot find the sucker. Any suggestions where I should look?
Thank you!
Actually I just found it, now to remove and find a replacement. I read where this part is discontinued, any help on a suitable replacement is greatly appreciated!

EldoradoBill · September 24, 2016, 09:08 AM

You can replace with a standard 109 relay but lose the prime feature and no start shutoff feature. Or contact these folks and have your original repaired (they repaired my wiper module) http://www.fsip.biz/

Bill

Rickf1985 · September 24, 2016, 10:24 AM

Quote from: Robear on September 23, 2016, 09:48 PM
I have a 86 winnie c30 chieftain. I suspect the fuel relay switch is bad, but for the life of me I cannot find the sucker. Any suggestions where I should look?
Thank you!
Actually I just found it, now to remove and find a replacement. I read where this part is discontinued, any help on a suitable replacement is greatly appreciated!

If you are going to throw that one out can you mail it to me? I will pay the shipping. I am curious to see if it is a common failure as CapnDirk found.

If it is then maybe I can get into the repair business myself just to help others out.

And if anyone else has a failed relay they are just sitting on let me know.

Robear · September 24, 2016, 03:41 PM

I'm going to pull a hose and check for fuel flowing before I take it out. If I decide to throw it away, I'll mail it to you!

Robear · September 24, 2016, 03:45 PM

Quote from: EldoradoBill on September 24, 2016, 09:08 AM
You can replace with a standard 109 relay but lose the prime feature and no start shutoff feature. Or contact these folks and have your original repaired (they repaired my wiper module) http://www.fsip.biz/

Bill

When I look up the 109 online,It says its a VW Relay switch. Will this work? Thanks!

EldoradoBill · September 24, 2016, 08:13 PM

Standard products RY109 my fingers type faster than my brain lol

BrianB · September 25, 2016, 09:22 AM

Quote from: Rickf1985 on September 24, 2016, 10:24 AM
If you are going to throw that one out can you mail it to me? I will pay the shipping. I am curious to see if it is a common failure as CapnDirk found.

If it is then maybe I can get into the repair business myself just to help others out.

And if anyone else has a failed relay they are just sitting on let me know.

I am an electrical engineer who designs circuit boards. I would be interested in reverse engineering the circuit. Might not be hard to make a pin for pin replacement. Maybe I could intercept the package before sending it on to Rick.

Oz · September 25, 2016, 07:14 PM

We need a CWVRV drone for intra-member package transfer!

TerryH · September 25, 2016, 07:52 PM

Great idea!
Even better if it could legally cross the 49th parallel.
Both ways.

87Itasca · September 25, 2016, 10:37 PM

Man, I like where this is going.

CapnDirk · September 26, 2016, 10:50 AM

Robear: You might crack it open and take a look. It was made to have the cap snap off.

Oz: Great idea! we could lease it to the government when not in use for packages.

Robear · October 16, 2016, 07:13 PM

I pulled the fuel line along the frame and had the engine cranked. Fuel was flowing. I decided to change the mechanical fuel pump, and it runs much much better but still craps out when pulling a slight grade. I can't figure it out. Im ready to throw in the towel, sell it and wait 10 years, retire, and buy a Pickup truck and Tow Trailer!

Rickf1985 · October 16, 2016, 08:18 PM

Have you changed the filter halfway up the line from the rear?

CapnDirk · October 20, 2016, 07:48 PM

Robear:

The only other restriction, failure point would be the sock filter at the bottom of the tank, and/or the small filter in the carb at where the fuel line enters.

kansascat · October 22, 2016, 09:56 AM

I had one starving for fuel on hills that turned out to be the rubber line that goes from the steel line to the mechanicle fuel pump was curved to sharply and was almost pinched off...it got worse when hot due to the rubber softening some.

BrianB · October 23, 2016, 07:18 PM

Quote from: kansascat on October 22, 2016, 09:56 AM
I had one starving for fuel on hills that turned out to be the rubber line that goes from the steel line to the mechanicle fuel pump was curved to sharply and was almost pinched off...it got worse when hot due to the rubber softening some.

Interesting....

87Itasca · October 26, 2016, 09:42 AM

Where is this relay located? I've found a parts Windcruiser, and I might as well pull it off to have a spare in case.

Rickf1985 · October 26, 2016, 09:54 AM

Usually inside the dogbox on the drivers side.

CapnDirk · October 27, 2016, 02:36 PM

If you put your foot on the gas pedal and rotate it right so it connects to the sheet metal, you are just about touching the screws that hod it to the inside of the engine doghouse.

I you find a usable relay (or not usable) SAVE IT! Others here are interested. Assuming the same part number.

ClydesdaleKevin · December 08, 2016, 10:29 AM

You can also rewire it to a regular relay like I did. You lose the safety shutoff feature that stops the fuel flow if the oil pressure drops (crash protection), but I was okay with that. Works great!

Kev

ClydesdaleKevin · December 08, 2016, 10:42 AM

I found the thread where it describes in detail exactly what relay I used and how I wired it in to replace the obsolete relay...thanks to a lot of help from folks like Dave! Still working great and I haven't had ANY vapor lock or fuel delivery problems since. Sweet! http://www.classicwinnebagos.com/forum/index.php/topic,8795.0.html

Kev

tmsnyder · December 15, 2016, 04:56 PM

How much are these relays going for? Is there much demand?