450-Mile Ride Today + Possible Fuel Pump Issues

[Lotsokids]

I synced my carbs and installed new rear brake pads this morning, and headed south 200 miles to Dallas, TX - just for fun. Perfect weather!

BUT... on the way back, after about 70 miles, I felt the engine lose a couple cylinders, followed by the rest. I coasted to the side of the road (in the middle of nowhere). After a while it cranked up and ran well... for a few minutes, then died again. Turning the key on and off, the fuel pump would click for about 15 seconds EVERY TIME, like it wasn't priming properly. This happened about 5 times, but it got me home.

A key factor is the pump runs a long, long time (about 15 seconds) each time the key is cycled on and off, indicating it does not prime like it should.

I've read a lot about fuel pump issues. The 2 things to check first seem to be:
1. Check for cracked feed line to the pump (drawing in air)
2. Check the diaphragm in the pump

 

[dannymax]

I synced my carbs and installed new rear brake pads this morning, and headed south 200 miles to Dallas, TX - just for fun. Perfect weather!

BUT... on the way back, after about 70 miles, I felt the engine lose a couple cylinders, followed by the rest. I coasted to the side of the road (in the middle of nowhere). After a while it cranked up and ran well... for a few minutes, then died again. Turning the key on and off, the fuel pump would click for about 15 seconds EVERY TIME, like it wasn't priming properly. This happened about 5 times, but it got me home.

A key factor is the pump runs a long, long time (about 15 seconds) each time the key is cycled on and off, indicating it does not prime like it should.

I've read a lot about fuel pump issues. The 2 things to check first seem to be:
1. Check for cracked feed line to the pump (drawing in air)
2. Check the diaphragm in the pump

I had some strange fuel pump issues and pulled all the fuses, cleaned and di-greased them and the problem seemed to go away. Don't see how that could be your problem but worth a try I guess. :confused2:

 

[Elimax]

One thing I'd do is to check your fuel filter...it may be clogged, dirty, or need to be replaced. I believe that would hinder appropriate gasoline flow.

Eimax

 

[Traumahawk]

One thing I'd do is to check your fuel filter...it may be clogged, dirty, or need to be replaced. I believe that would hinder appropriate gasoline flow.

Eimax

+1. So for some odd reason, your basically running out of fuel. So, possible causes float level sticking low (but usually they will stick high........and then you have fuel coming out the vents).

If the pump is running constantly, make certain that the rubber diaphragms are still in place in the pump. With them being in place, it allows the pump to build pressure.

You can check where the fuel pump plugs into the harness. The should be by the right rear cylinder, right next to the frame. Might be corrosion.....etc.

Like Danny said, check fuses........etc.

 

[sdt354]

I'm thinking the diaphragm in the pump got out of place. Because the pump is running, and so long. If you could check a drain line after stalling, it would verify fuel as the issue.
Elimax just reminded me of something I haven't changed in a while.

 

[Lotsokids]

One thing I'd do is to check your fuel filter...it may be clogged, dirty, or need to be replaced. I believe that would hinder appropriate gasoline flow.

Eimax

New fuel filter installed just a couple weeks ago.

Another note is that when I start the bike, I can hear (and feel) the fuel pump clicking at idle. I've never heard the fuel pump on my 3 previous V-Max's at idle. I'm thinking it's the diaphragm.

Concerning the $16 Chinese fuel pumps - Seems nobody trusts them, yet nobody has had problems with them (once the bracket is changed). Can anyone confirm this?
I found a new OEM pump for $200. I'm tempted to buy it for some peace of mind.

 

[Bill Seward]

I put in a Chinese fuel pump a couple years ago. Clicks really loud, but has worked fine. Cheap insurance, maybe get one and carry it with you for a while in case it happens again. Easy enough to swap out even on the side of the road...

 

[Lotsokids]

Today it ran good for about a block, then died. Pushed it home. I pulled the fuel pump apart, and everything looks good and in it's place. The internals were actually in very good condition. It clicks for about 5 or 6 seconds - every time the key is turned on. It's not priming. I cleaned the connector and all fuses. Put it all together and noticed the fuel filter was not full. When the pump is running, I see some movement of fuel (vibration), but I don't believe it's pulling fuel from the tank. I checked the fuel hose between the tank and fuel filter (the U-shaped one) for holes or cracks, but it looked fine. All new fuel lines to the pump and carbs. So I wonder if my tank has garbage plugging the tank outlet. The old fuel filter was full of garbage, but it ran well.

Tomorrow I will connect a fuel line directly from the filter to a gas can to see if it draws it from the can. That will identify a problem in the tank.

 

[Traumahawk]

When it dies, take the fuel cap off, and then try to run it again. If it will run without the full cap off, the fuel vent is plugged.

 

[Lotsokids]

When it dies, take the fuel cap off, and then try to run it again. If it will run without the full cap off, the fuel vent is plugged.

Yep. Tried that. No difference.

So here's the events from today. I pulled off the fuel line from the tank and installed a new fuel hose and put it into a gas can. The fuel pump ran a little and primed perfectly. After 3 times turning the key on, it stopped pumping and was primed completely. BUT when I attached the hose to the tank, it keeps running for 5 seconds over and over. There is a little rust in the tank, but I can't see the pickup to see if it's clogged. I drained the tank (small plug on the bottom) but no big debris cam out.

Still puzzled, but I know the pump, fuel filter, and fuel lines are good.

 

[Fire-medic]

Guessing you don't have the stock exhaust, as it appears nearly impossible to access that plug without pulling the exhaust megaphones/resonator box, or the rear wheel and fender.

Yep. Tried that. No difference.

So here's the events from today. I pulled off the fuel line from the tank and installed a new fuel hose and put it into a gas can. The fuel pump ran a little and primed perfectly. After 3 times turning the key on, it stopped pumping and was primed completely. BUT when I attached the hose to the tank, it keeps running for 5 seconds over and over. There is a little rust in the tank, but I can't see the pickup to see if it's clogged. I drained the tank (small plug on the bottom) but no big debris cam out.

Still puzzled, but I know the pump, fuel filter, and fuel lines are good.

 

[Lotsokids]

Guessing you don't have the stock exhaust, as it appears nearly impossible to access that plug without pulling the exhaust megaphones/resonator box, or the rear wheel and fender.

Correct.

 

[Lotsokids]

Rode to work this afternoon with no trouble. Not much faith in it, though.
I ordered a new fuel line - the short U-turn one from the tank into the filter. I have a new hose installed in that place, but it's a sharp bend. I put a couple hose clamps on it to keep shape until the new formed line arrives.

 

[Lotsokids]

Update:
After replacing the fuel hose from the tank to the filter, I've ridden 65 miles with no problems at all. I still don't trust it, so I've stayed around town.
Still waiting for the OEM U-shaped fuel hose to arrive.

I may be on to something here...

A quick question: Do any of you audibly hear your fuel pump clicking at idle?
I've owned 4 V-Max's now and never heard the pump running after the engine is started. I thought once it's primed with the initial key-on, it would just run occasionally to maintain positive fuel pressure - not constantly run. :confused2:

 

[Bill Seward]

I do, but it's not a constant thing. And the Chinese pump is loud as hell. Even with the Delkevics I can hear the click.

 

[[email protected]]

Once the bowls are full first time of the day I've never heard the pump afterwards

Sent from my SM-G930V using Tapatalk

 

[Traumahawk]

I hear just a click every so often.

 

[SENTíNEL]

Just the initial priming on my ‘88 V-MAX, and then all good. V-Boost, that’s another story entirely, but I won’t hijack your thread!


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[Lotsokids]

Update: Dec. 4

A couple times it died again. Same spot, which is interesting. Both times I started it cold, rode about 2 miles to an on-ramp to the highway, then full throttle nearly redline blast getting on the highway. I saw 85, then backed off. It immediately started losing power and within 1/4 mile it was dead. Turned the key off and on, and fuel pump ran fine (audible clicking). Restarted and it ran perfectly for the next 10 miles. Both times, same thing, same place, same results.

At idle, I can hear the fuel pump clicking constantly. Makes me think it's the pump. But again, I disassembled it and the diaphragm looks fine.

I'm tight on money, but I think my next step is to dump $200 on a new OEM pump for peace of mind.

When the weather warms up, I plan to take more 3-hour rides to Dallas for Dickie's BBQ. Yeah, it's that good, and we V-Maxers don't need a big excuse to ride, you know. :biglaugh:

 

[caseyjones955]

I recall looking for new pumps when mine was getting louder. It seems to have improved on its own but I did keep this info handy. 2 bones for an OEM is not a good option for be, a Chinese no-name eBay special is out of question. I think some of these others are Chinese but warrantied through local retailers like Autozone. Maybe a reasonable compromise if you dont have the burning seething contempt for Chinese materials/workmanship that I do.
http://www.vmaxforum.net/showthread.php?t=18560

Just thinking out loud here...
I wonder if you could get a boroscope to veiw the pickup in the tank bottom. If its got some crap in there blocking patancy of the line you might be able to get creative with a shopvac and a length of hose while backblowing through the pickup with compressed air. Never tried it but I sure would depending on what I saw resting on the bottom of the tank. At any rate I hope the solution is cheap and lasting. Glad you got some bbq and ride time in.