97 ST1100, fuel pump quits when 4 gal down.

Riding my 97 ST1100 Veronica yesterday, 179 interstate miles since the last fill up, pretty warm (90s), had just passed through a somewhat heavy but short rain squall, full throttle and no response. Only 1/2 mile to exit 44 on 40 East!!! AARRGGHH!. And all uphill. Turns over fine, a little sputter under full choke, no start. Fuel gauge reads slightly above 1/2 tank, no fuel light on. Start pulling tupperware. Correct tools in tool kit, except for a bandaid for when I removed the top of my knuckle on that stoopid :censored little arm that sits strategically directly above the fuel cap. Whip out my Zippo to visually check the fuel level in the tank.....kidding, just checking to see of you are paying attention. My LED flashlight indicates about what the fuel gauge does, above 1/2 tank left. Disconnect the fuel line running to the fuel filter, turn key, no fuel comes out. Oh, btw, my vacuum fuel cutoff is long gone, never a problem. I grab a short piece of wire, connect it to the positive battery post and to the farthest left connection on the tank plate, pump works fine. I then leave the wire connected and Veronica fires right up. Disconnect wire, reinstall tupperware, reconnect wire by using the existing connector to slide over the jumper to hold it in place and restart, put on seat and go to suckle 4 gallons from BP. Oh, she stopped running when I put the kickstand down while in gear. Pull seat, remove jumper wire, reinstall existing connector, she fires right up no problem. Sorry so wordy, but thats what happened. Why would my pump stop working with 1/2 tank? It did exactly the same thing once before. I really don't want to stop and refill that often!!

Re: 97 ST1100, fue lpump quits when 4 gal down.

Funny attention getter (Zippo)...

Nothing worse than an intermittent condition. Looks to me that you're working on the troubleshooting list in the Honda Service Manual. If it'll turn over its not the Bank Angle Sensor. If you can get the pump working by bypassing its normal electrical circuit, I suspect a (an intermittent?) Fuel Cutoff Relay (looking at the circuit on a colored wiring diagram link) problem. Do the check shown in the manual. Can't explain how the fuel level in the tank might affect the pump operation as far as getting power to it... Maybe a combination of accumulated electrical resistance in the OEM wiring (lowered voltage) and an ailing fuel pump (heat related bearing resistance) causing the pump to stop; whereas 13V+ direct from the battery can overcome that to drive the pump...(?)

Good luck and keep us poSTed.

Regards, John

Re: 97 ST1100, fue lpump quits when 4 gal down.

Some have reported the pump quitting when the fuel level gets to a certain point, presumably due to lack of the cooling effect of the gas. Then it would start up later when it had cooled down. Might need to look for an aux fuel pump soon.

Re: 97 ST1100, fue lpump quits when 4 gal down.

When I pulled my pump out of the tank on my 98, - it was pretty well gummed up. I would agree with John that maybe the full voltage from the battery is giving it enough torque to overcome any resistance.

The pump sits just above the bottom of the tank on a bracket - below the low fuel warning sensor. So you would really have to be low on gas I would think to get it to overheat. If I was you I would pull the pump out and take a look - you maybe surprised what is in your tank after all these years

Re: 97 ST1100, fue lpump quits when 4 gal down.

As Bill said, it could be a weak pump that is seizing up when the fuel gets hot. I might have become loosened when you increased voltage, or it was just a coincidence that it cooled off enough to work again. You might want to check out the following link: http://home.insightbb.com/~mmartin36/FPDiagnostics.htm

You might find this one usefull: http://johnandbecci.info/Hints/fuel_pump.html

Edit: turns out my link's pretty much the same as STpaulK's.

I ran into the same problem a while back. Left me stranded on the side of the road on my way to a customer.
When cold, the flow rate/pressure were within spec, but when things warmed up this dropped to < half of that..

Uncle Phil has had similar problems I believe, fairly sure it was low, but not empty, fuel and heat related on his earlier bikes......

Also fairly sure he replaced the pump and problem went away......

Boy there are a lot of these failed fuel pump threads lately. Another option to insure you have a working pump is add one of these http://www.aircraftspruce.com/catalog/eppages/facetpumps.php
The 40105 is the one I got and so far I don't know when or if my OEM pump cuts out as the Facet kicks in and all has been good. Just put it in-line after the filter. It sits nicely where the Vacuum Shut Off used to be.
Mark

More info -- How to fix: replace OEM pump motor with an aftermarket:
https://www.st-owners.com/forums/showthread.php?89040
edit: and a little more added here:
http://www.st-riders.net/index.php?topic=7042

Wow, thanks to all!! I have a lot to do now...I have a voltage meter on the dash and it NEVER gets above 13.1v, usually around 12.6v. The reading is a little higher directly on the battery. Sounds like dirty contacts on the alternator? The battery connections are very clean. As an aside, after checking the owners manual it stated the "FUEL" light on the dash should come on for a few seconds when ignition switched on, then go out. Mine didn't ever do that since I got it used a few years back. (Best purchase I ever made IMHO.) Thinking this might be related I checked it and there was no bulb in the holder. Wierd. I installed a bulb and now it seems to work correctly, at least on the initial turn of the key. I suppose the next thing to do is siphon gas out and make sure the indicator works when the fuel level is low and also see if/ when the pump shuts off. Thanks again to everyone for the info and links!! ST owners rule.

Glad you are heading down a productive troubleshooting path. That burnt orange ST looks familiar. Where did you find it? Do you know the original owner (who painted it.)? Or was it a Canadian model?

Yah, lots of trouble shooting this winter, for now I will stop and top her off every 90 miles or so. I have NO idea who the original owner is. I bought the bike from Kevin Varner through MR Honda here in Asheville NC, it was a rather scratched up factory Red when I got it but had it repainted at a local paint shop. I think she was cobbled together from a few STs and had been laid down hard at least once. No locks the same, damage hidden under body work, etc, etc. I think she shined up well though!!

Hi,
I had the same problem with my 1997 ST1100 when I got it at first. Would die with the gas gauge at 1/2, will look in the tank, and it still has gas in it!
Thanks to one of our fellow ST'ers, took the tupperware off, and looked in the gas tank. There is a rubber hose that connects to a metal pipe that you should be able to feel/see on the right hand side of the tank (with you facing forward). In my case, that rubber hose had come off.
The fuel pump gets gas 2 ways. Through the pump, and through this rubber hose (when the gas falls below a certain level). So, essentially the bike would run till the gas goes below this level, and when it could not get any more (when the gas fell below "that" level, the bike would stall).
I connected the hose back, put a clamp on it (didn't want any repeat issues) and have not had a problem since!!

https://www.st-owners.com/forums/showthread.php?48353-Ran-out-of-gas...again&highlight=

I thought the metal pipe you are talking about is actually a 'vent' for the fuel pump??

If you look down the filler neck on the right hand side (seated on the bike), you will see the pipe. Here is a pic from inside the tank - you see the pipe make a 90 degree turn and go up into the filler neck area. If it was an intake for the fuel pump, by connecting the hose - you would have raised the intake level

The first pic shows where the rubber hose connects to the pipe - just under the top of the main tank area

GitSum said:

I thought the metal pipe you are talking about is actually a 'vent' for the fuel pump??

If you look down the filler neck on the right hand side (seated on the bike), you will see the pipe. Here is a pic from inside the tank - you see the pipe make a 90 degree turn and go up into the filler neck area. If it was an intake for the fuel pump, by connecting the hose - you would have raised the intake level

The first pic shows where the rubber hose connects to the pipe - just under the top of the main tank area

Click to expand...

You are right, I meant when you take the pump off....it should be like in pic 1. In my case that hose with the white paint was disconnected.
Thanks!

scwten13 did you get your bike sorted? If not I could ride up one day and help with a fuel pump replacement. Only 40 bucks for an Airtex 11000 at Advance, and an hours time.