My Interceptor has suddenly decided not to start any more. It ran fine the first few times I took it out this year, but early this week it started only briefly and kept dying as soon as I twisted the throttle a bit. It got worse until it just wouldn’t start at all. Yes, the petcock was turned on, the tank is full, and the petcock itself is nearly new. It seems like a fuel starvation issue and I’m suspicious of the fuel pump. This one is 33 years old, so it wouldn’t surprise me if it died. At this point, I thought I should test my theory and pull the tank, connect an aux tank, disconnect the fuel line feeding the carbs and see if it pumps fuel when I try to start it. I read in one of the threads here that there's a fuel pump relay that sometimes fails, so I'll check that as well. It would surprise me if the fuel filter suddenly became totally clogged, but I guess that should be ruled out too.
I heard a rumor that there's a mod that can be done to eliminate the need for an electric fuel pump. If someone can point me in the right direction, I'd like to read up on this.
Thanks to all who have suggestions and advice for troubleshooting, mods, alternatives, etc.
Make sure your tank is venting properly. 49 state models vent thru the cap. They can get clogged and prevent fuel from being able to be pumped out of the tank.
Find the starter fuel cut relay and jump it to see how the pump responds. My experience with Interceptors is that the relay is usually the culprit, but of course pumps can go bad. I have never had to replace a pump that had been in at least semi-regular use (yet). I install toggle switches in parallel so I can essentially jump the relay if needed. Some just jump it and eliminate it. It is a safety feature, but I also like the ability to have the key on with out the pump wanting to kick in if I am working on something on the fuel system.
The first, according to probability theory, suspect should be the pump relay. Cap'tn 80's switch (i'd suggest a push-button) is a must-have item for quicker starting, especially if the bike's been unridden for awhile. :comp13:
The first, according to probability theory, suspect should be the pump relay. Cap'tn 80's switch (i'd suggest a push-button) is a must-have item for quicker starting, especially if the bike's been unridden for awhile. :comp13:
A push button is a little harder to get home with when the relay fails out on the road. So if I'm going thru the process of installing one, it will be a toggle.
I finally had a few minutes to check out the relay. I shorted out the black and white leads and tried starting the bike to no avail. I drained the left bowl and noticed that after a fair amount of cranking,no new gas had been pumped in. Next chance I have, I'll pull the tank, disconnect the fuel pump outlet hose and see of fuel comes out when cranking. If not, then I'll remove it and try the bypass.
As soon as you eliminated the relay by jumping on the harness side, the pump should have immediately started pumping. I would try again verifying that you are then getting power to the pump. If you are getting power to the pump with the relay bypassed, give the pump a good jolt with a rod of wood or a screwdriver handle and see if you get anything.
I wouldn't then trust that pump if you get any sign of life, but it could tell you that all everything else is alright.
Today I hooked up my aux fuel tank directly to the carbs and the bike fired right up. I've already bypassed the pump and it seems to run fine. I'll take it out for a short ride once the roads dry off and make sure it's all set. I also want to kill the power to the pump should it ever want to come back to life.
Thanks to you all for your help, especially Mike - Captain 80's.