Full Version: Fuel pump, electrical
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1984 Interstate, bike had set for about two weeks.

Would not start, fuel pump was not pumping gas.
Check and it had no power to it.

Bike turned over fine to start with, but I ran it down working on it.

Put the bike on the charger, then it would start, fuel pump ran fine.

Charging system is working. Battery shows good voltage.
Used a load test on the battery, still shows good.

My thoughts:

Without a full charge fuel relay will not engage?

Maybe have a dead cell in battery, not always showing up? I thought a load test would always show a dead cell?

Might need new fuel pump relay? I need to know where that is?
Might help
That is a very helpful attachment! But I have no point of reference for the picture with the relay in it. Is that the front or the back of the bike, right or left side?

I have the battery fully charged and am tracking the voltage each day to see if maybe something is drawing the battery down slowly.

I suspect the coil of the fuel pump relay may be weak and require "maximum" voltage to engage, perhaps a new one would be less picky.

Or it could be that I have something drawing the battery down more than I think and the voltage gets below what the relay needs.

Or maybe just a better battery is needed.
I have heard several on here complain about "cheap" battery's, and mine was that.

It seems to run great when ridden frequently it is only after it sat for a week or two that the problem developed.
front right, under the ign coils, remove the false tank to access.

Dont buy cheap batteries. or keep the battery on a battery tender (junior) when not riding.
Did you ever wonder why a battery of the same (physical) size can have different length warrantees?
It depends on quality of material, (obviously), number of plates in each cell, the thickness of the lead on each of the plates, whether or not there are debris tubs and how deep the tubs are.
The high compression engines require high cold cranking amperage to overcome that compression. Harley-Davidson owners are well aware of the pit falls of ’cheap’ batteries.
Bottom line is to buy the best you can afford at the time of need, or wait until you can buy a good, quality battery.
Poor quality batteries can have you chasing your tail. A poor quality battery will give symptoms of a starter needing service or misfiring due to weak voltage at the coils among other gremlins.
Electrons are funny little fellows…..

The contact points on fuel pumps can be serviced and additional service can be achieved from them.

I was able to get over 130,000 miles out of mine before it started to leak out where the wires went in. I opted NOT to try and repair and instead, replaced it with a low mileage, used unit I found locally. Others have reported many, many more miles than me but I think it is the luck of the draw.

Good Luck!
As of last night, the bike has been in my garage now sense Friday, the battery seems to be holding steady , I think 12.7 volts.

I did dig out my load tester and it also showed the battery as good.

I will continue to monitor the battery condition for a few more days. It would appear that there is nothing major pulling it down all at once.

I will try and start it again before the weekend. I am assuming that as long as I have good voltage it will start, but you know what happens when you assume...

Thanks for the help and support so far. Buying a better battery come spring would not be the worst thing in the world.
if the battery is not sealed, then using a hydrometer to check for specific gravity of the fluid of each cell will indicate the condition of the battery.

You know what they say when you assume! Dodgy

The battery continued to maintain 12.7volts. Saturday morning I tried to start it, I was completely surprised when it would not start! Same condition, as before. No fuel, but also no fire! Huh

I started playing with the kill switch (I never use the kill switch). You can see the speedo jump slightly as you flip it on and off. I switched it while trying to start the bike and I got a slight backfire. So I took the housing apart, and sprayed the switch with cleaner, then checked the connections, everything looked pretty good for a bike this age.

After putting it back together, the bike has started every time, so far...Blush

(The battery is a gel type, but cheap)
When in doubt, follow the path of the electrons from source to final device, checking all connections and contacts for a proper connection and clean surfaces, and ye will find the solution.

The bike is still in my garage, for the winter I think. Been starting it once a week or so.
So far everything looks good, I think it was just the kill switch.
Always buy the best battery you can find for these GL1200s not the cheap ones this is the heart of the electrical system. If there is anywhere you want to put out the extra expense its here,never mind chrome and frills this is where it counts. Been there done that.A shiny bike with lots of chrome but won't start is just a show piece. Just my 2 cents.