Anyone use a fuel pump on their scoot?

my 95' yamaha 600R had a fuel pump and was carbed. the lower pat of the tank was below the carbs so no gravity flow there. it was a tiny pump mounted outside the tank, and it has a built in pressure switch to turn it off. i got one real cheap on ebay awhile ago, just waiting for some project to put it on. i think putting a pump on would cover up your problem, something is wrong, i would start by checking the petcock, or maybe just go buy a Pingle. good luck

RetroRiceRocketRider wrote:

....My suggestion would be to pull the tank and drain it into a clean, open bucket/clear container so that you can check for debris/sediment. Then remove the petcock and thoroughly check the filter (and both the "ON" and "RES" tubes in it) for any signs of clogs....

RetroRRR and BlueMeanie you are both on the right track as far as I am concerned.
The reason I installed filters in the first place is because of what I did shortly after I bought the bike in Sept. last year.
I had light, internal tank surface rust which I did not feel was serious enough to warrant a full assault. I did, however want to "fix" the rust and prevent further rust formation. However, the testimonies I read about tank treatments were not very encouraging. Well being as I am a rocket scientist, :woohoo: :woohoo: :woohoo:
I wanted to test a product that I have used with excellent results in the past, but never in the tank. That product is called 'rust transformer'. I treated my tank using what I felt would be a good, thin coat and set it in the hot summer sun in, like Aug. or Sept. this year. I rotated the tank many times on several days, in an attempt to bake the transformer but not the paint till I felt it was well cured. I then gave it more time to totally cure. Next I filled the tank with fuel and let it sit for a month or so. After I adjusted my valves a few weeks ago I was ready to install the tank. I removed the petcock and trapped every drop of fuel for inspection. I figured that the rust transformer would let go of the tank and would be visible as small, thin chips much like flaking paint if it was going to fail at all. That seemed more likely to me than it completely dissolving, back into the gas.
Everything looked great so I put 'er all back together and, because the gas still looked and smelled like new, I poured it back in, and off I went, riding into the sunset.
I feel like I need to keep the filters in place till there is no chance of the tank treatment failing.

Post edited by: JimatMilkyWay, at: 2007/12/02 00:12

Thinking the same thing as RRRR, I pulled the petcocks, but found the screens to be clean. But I then realized they flowed like Niagara Falls with the filters off, but flowed like they had an enlarged prostate when the filters were on... just a trickle, that is.

loudhvx wrote:

....but flowed like they had an enlarged prostate when the filters were on... just a trickle, that is.

I can't personally relate to that trickle action:laugh: :laugh:
But tell me, if I got three Pingles, would triple trickle do the trick? :silly: !!!

JimatMilkyWay wrote:

Next I filled the tank with fuel and let it sit for a month or so. After I adjusted my valves a few weeks ago I was ready to install the tank. I removed the petcock and trapped every drop of fuel for inspection. I figured that the rust transformer would let go of the tank and would be visible as small, thin chips much like flaking paint if it was going to fail at all.<br><br>Post edited by: JimatMilkyWay, at: 2007/12/02 00:12

If you left the petcock on there during the tank treatment (or reinstalled it before the treatment had time to fully "set"), that's probably where your problem is.
It's likely that some of that "rust transformer" made it's way into the petcock, and is partially blocking the fuel passages in it when at a low fuel level.

IMHO, the petcock (and perhaps the fuel line) is the only thing truly suspect at this point.

Post edited by: RetroRiceRocketRider, at: 2007/12/02 10:42

I also was had hammering or ticking petcock that acted like a mini fuel pump (if the fuel lines weren't on tight fuel would be spurting from the leaky areas). Attempted to clean the petcock especially the check valve found alot of black gook in there(check valve). That didn't help, still ticked,and figuring the check valve does not come in the rebuild kit(45-50 buckaroos) replaced it with a manual single outlet petcock AND FILTERS from z1. On another post WiredGeorge said in his experience this petcock will flow sufficiently. However, 3 things I noticed, 1) If I ran the bike one day and the next try to start it the next, it would take alot of cranking to get it to fire. Then I saw that if I open the petcock before attempting to start and watched the fuel flow (clear lines)it would take 15-20 seconds to load the filters and lines(slooooowww)the bike would THEN fire immediatly. 2) I also noticed lean conditions when the tank was low but not reserve, fillerup no problem. 3) when I did get to reserve, it would take a looong time to start running right, DANGEROUS, luckily I was in town and not on the highway. Now after reading this thread I'm going to pull the filters ( I was heavily suspecting these anyway)as there is already a filter on the petcock.

P.S. my son did some experimenting with flow rate of fuel with 6" of 1/8" line vertical-best, horizontal-slower but not bad, even U shaped-worst, took twice the time to flow the same amount of fuel asthe other two.We're going to do the test again with 1/4" line. Bottom line, if you have extra long fuel lines that go back up as high as the petcock or higher this will reduce flow rate.

Hope this helps someone.

RetroRiceRocketRider wrote:

JimatMilkyWay wrote:

Next I filled the tank with fuel and let it sit for a month or so. After I adjusted my valves a few weeks ago I was ready to install the tank. I removed the petcock and trapped every drop of fuel for inspection. I figured that the rust transformer would let go of the tank and would be visible as small, thin chips much like flaking paint if it was going to fail at all.<br><br>Post edited by: JimatMilkyWay, at: 2007/12/02 00:12

If you left the petcock on there during the tank treatment (or reinstalled it before the treatment had time to fully "set"), that's probably where your problem is....

Nope. I built a wood seal plate and made a gasket just to seal the petcock port for rinsing the tank before doing anything. I taped the port with duck tape when I sprayed in the transformer. This was just to prevent drips. The screen and petcock was removed and inspected when I drained the test gas from the tank.
One thing that is sort of surprising is how many posters responding to this post, with experiences which don't seem leaps and bounds different from what I have related.

2 things come to mind:

1. I've heard that the small cone shaped filters do not flow enough for most bikes.

2. When I bought my KZ the tank was full of crud. It would usually run OK when full, but later on it would die or run REALLY badly. A good cleaning solved it.