What to do when your fuel pump clicks like a SOB

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Thanks for the info on a new fuel pump, they still sell them after almost 3 years. That good enough for me, I bought one today. Mine are toast.
 
I had the same issues with mine popping out every hundred miles or so. I replaced the diaphragm with one out of an old venture fuel pump. The venture diaphragm was thicker than the vmax original but it has worked very well.
 
Is this what it sounds like?
Video:
http://vid124.photobucket.com/albums/p31/81monte/IMG_1470.mp4
Bike still seems to run fine and there's now leaks....I guess I'm checking that rubber diaphragm this weekend...possibly getting a new fuel pump



People have used this one. I think someone had to rotate the end, if I remember right, but you can even take these apart if need be.
http://www.ebay.com/itm/291222183638?_trksid=p2055119.m1438.l2649&ssPageName=STRK:MEBIDX:IT
 
You will need to pull the large rubber diaphragm through the original bracket to get it to bolt up. Not the same as the 2 small diaphragms that usually flip over and make the pump keep running.
 
This sounds completely different than usual. Normally it's 3-4 seconds of slower clicks, sometimes even just a couple clicks if I was just running the bike recently. Right now, it will rapid fire click for 5 seconds every time I turn the key, even if I don't start the bike. It's never done this before. The bike has been solid for the first week on the road and now this is something new.
 
After it stops clicking, and before you start the bike, turn it back off, then on again. If it clicks for 5 more seconds before building adequate pressure, you may have a problem. It only takes a few minutes to remove & disassemble the fuel pump to have a look at it's innards. You might find one of the tiny rubber diaphragms out of it's retainer hole. If both fall out at the same time, you'd be hard put to get enough pressure out of the pump to ride the bike normally.
 
Yeah, yesterday it was doing it every time I'd turn it off and on. Could temperature have anything to do with it? It was pretty hot yesterday and it only did this in the afternoon, not the morning. Now, this morning it magically fixed itself! Just a few clicks like normal...wtf
 
Yeah, yesterday it was doing it every time I'd turn it off and on. Could temperature have anything to do with it? It was pretty hot yesterday and it only did this in the afternoon, not the morning. Now, this morning it magically fixed itself! Just a few clicks like normal...wtf

Temps shouldnt have anything to do with it.

Mine will usually click like hell once a year, and when I am about ready to tear it apart, it will stop, for about another year. I dont really know what the cause is.....or what fixes it. It is an intermittent problem, and until it does it more often, I'm not touching it.
 
Primitive Prime as follows, tear cellophane sandwich bag or similar to fit over gas fill, blow in tank as fuel pump is running, watch for fuel in filter, hear pump go under load, fuel line is full from tank to carbs.
 
The pump on my '96 test engine sounds just like PMaxx's in post #44 but both diaphragms appear to be in place. Is there another possible cause? Thought I read somewhere on the forum about 3 o-rings, located somewhere in the fuel pump, that could cause this type of issue. :confused2:
 

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I have been screwing around with this very same issue today.

Turned the key for the first time and fuel srarted klicking and then stopped. I cycled it five times to the same result. The carbs were removed prior for dismantling and cleaning.

Did some fine tuning on carbs and went for a ride down the street and stopped in a parking lot. Bike idle for bit and wanted to die. Went for a big longer ride and back to house. Bike idle for a bit and died.

Cycled the key and each time the fuel pump pumped for it's cycle. Pulled the seat off and pulled the fuel filter from the holder.

My fuel filter is clear glass and noticed that it was empty. Turned the key and watched the fuel filter fill up. Turned the key off and watched the fuel filter drain out.

So took fuel pump off bike and took it apart and to my surprise, both rubbers were in place, as yours.

Decided to step away and do some research, so any insight on the solution would be appreciated.

Mike
 
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The test engine is the one that's acting up, I eliminated the metal tank in favor of the set-up pictured below.

When I first turned the key on it clicked so fast it was almost a buzz, a couple times like that and it built pressure and I was able to get the carbs tested....but it didn't seem like it was acting right, looking at the see-thru filter the pulse appeared slow and weak.

It has worked flawlessly for dozens of tests....now something's gone haywire. :confused2:

BTW since this photo was taken I changed the filter for a cone shaped sintered brass one.
 

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My year old fuel pump - a Chinese EBay knock off, I have to admit... started clicking like an SOB recently. I was ready to pull the pump and have a look inside, till I noticed the short gas line from the spigot on top of the tank to the filter wasn't clamped, I must have just jammed it on there when I got the bike running. The extreme end of the hose was a bit cracked and split. I got the side cutters out, and clipped off the bad part, and reinstalled the hose, with a clamp this time.
Clicking then went back to normal. I wonder if I was pulling in a bit of air along with the gas, and the pump wasn't building up pressure to shut off. There was no leakage of gas at all, but there were some bubbles in the gas in the filter.. The bike ran fine, so the pump was delivering sufficient gas, and if it was pumping any air into the bowls, it wasn't enough to cause a problem..

in any case, all seems well now.
 
There is also a set of contact points under the tail cover, I was thinking about drawing a points file across them, see what that might do....but haven't tried it yet.
Anyone ever messed with those points?
 

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