Fuel pump contact issues

I have posted a thread here about my bike intermittently not running. I have found the cause and think it is worth starting a new thread to discuss the issue. I have an 87 700 Califonia bike. Through a lot of troubleshooting in the last month or two, I have finally found the issues.

I am attaching four pictures. The first two are from the OEM pump I installed last year, the second two are from the new, aftermarket pump I recently installed
On another thread, I read a comment about a fuel pump maybe not being bad, but having bad contacts. For grins, I first verified that the fuel pump(s) had power and would not run. Then, using 400 grit sandpaper, I cleaned the contacts. Even though the ones from the OEM pump are obviously damaged, and the new pump is, well, new, this did the trick on both pumps and they both pump now.

On to the cause. My thought is that the fuel pump electrical plug is loose enough (it is definitely loose) to cause arcing. This arcing could somehow either send more voltage to, or ground out, the fuel pump contacts.

How does that sound?



Thanks,



Scott

 

I had pump issues early on getting my VF500 going, though I got a Mr Gasket pump, I switched back to the original OEM after I gave it a good cleaning. Contact points were warn though not as bad as yours, but it works flawless now. If you’re concerned about grounding check the wires, these old bikes have had plenty of time to wear the sheathing off. I did add some heat shrink tubing from the rubber gasket coming out if my pump up to the plug. The plugs are “loose” on my bike, but the locks hold them in place and I’ve cleaned all the contact points by hand - give that a try if you have not, you’ll see if there’s any place you’re grounding or not getting connection.

Good luck and have fun, these old bikes are wicked fun!

 

Thanks for that. Another thing I noticed is the clutch safety switch is not working. By that, I mean the bike will crank and start without the clutch pulled in. I'm not sure if this is new because until the other day, I never tried it (not even sure why I tried it this time...lol). The idea is to fix the clutch switch and replace the fuel pump plug. I sourced a weatherproof plug with wire ends that fit with zero wiggle room. In addition to those two things, I think I'll go through the entire bike, wire-by-wire, where they are exposed anyway, and check for wear.

Add to all of that, I'll keep a piece of sandpaper somewhere on the bike just in case.

 

Other than my Interceptor, I’m an off road rider, so by habit I always pull in my clutch when starting. Though I think it should start without clutch when up on the center stand in neutral. There are other much more knowing people on this site to help you fit
Gore that out. Yup going over the bike wire by wire is a process, I’m still doing it but also riding, I keep some fine grit sand paper and electrical tape in my tool bag, or should I say tool box I carry, I’ve also been using some dialectic tune up grease to keep Maine salt air and moisture out of the connectors as I clean them. So far so good.
Sounds like you’re doing things right. Keep it up!

 

It should start without pulling the clutch when in neuttral, weather up on the centerstand or not.

 

Here's the latest, and final solution to my issues. Ultimately, it came down to two issues, hopefully these finds will help someone else.

First off, the plug for the fuel pump was not connecting well. The female end of the bladed connector was too loose, this caused poor connectivity and explains why sometimes when the bike died I could unplug the pump and plug it back in to get it running. The solution was to replace both ends of the plug. I went with a new-style weather-proof plug and thought I had it licked. This led me to the second issue.

After replaced the plug, I decided to give myself some more access to troubleshooting if the bike died on the road. I removed the retaining screw on for the end cap on the fuel pump. This allows the cap to be popped off to examine the electrical end of the pump without needing tools. This worked out well. As we all know, with an intermittent problem, the bike has to be ridden to see if the issue is still there. I decided on a 25 mile trip to a shop down the freeway would work. I made it there but the bike felt odd. I made it almost home when the pump died again. Luckily, I was able to pop off the end cap. I checked it and found that the contacts would open, but not close. It's hard to explain all of my troubleshooting, but basically the issue was that the contacts were too far apart (you can actually see this in the pictures in my original post). I used a coin to bend the bottom bumper holder up a bit to close the gap and 2000+ miles later it seems like that was the final fix.

I know this is long-winded, but hopefully it can help someone else. I'll add a few words below as an aid for people searching this topic:

Chinese fuel pump
fuel pump contacts
fuel pump
electrical