Fuel gauge problem and running hot By vansmack2 (Read 770 times)

[vansmack2]

I ran my scooter today for about a half hour or so while testing my High Performance CDI box, and I had a few more problems. All testing was done with the scooter on the center stand, not any riding since I currently have it on an non-op registration until I am ready to ride it and pay insurance on it.

The scooter had started right up. I let it idle for about 15 minutes or so without any problem. The Fuel gauge was reading full, and the temp gauge was reading about mid point. It does not have a tach or clock, so nothing else to observe. I revved the scooter up high to test top end and held it for a minute or so. During the high rev test the motor ran fine, but the temp gauge went to the H, and nearly on the red line. Also, the fuel gauge dropped from full to empty. The tank still has a lot of gas, probably about 3/4 tank, so I know it is not empty. I shut the scooter off, turned it back on and then fuel gauge went back to full, temp still hot, and did not change. I revved the scooter again, and the fuel gauge went to empty again. The fuel gauge is now staying on empty.

I changed the coolant a few days ago. When I did so I left the radiator cap off for a while with the scooter running to purge the air. I filled it with new coolant as necessary each time it burped. I can see that the coolant is circulating, and the fan is running when the scooter is hot. It only started getting hot when I revved the scooter high for a minute or two.

I bought this scooter used, and only took a short test drive, so I don't know any of it history.

What should I check for the fuel gauge problem, and the temp problem?

[jenningsjosh]

Sounds like two different problems to me. or its something electrical that is throwing your gauges off... I am not sure either way... One of these pros will step up and help you out.

[vansmack2]

I think it is two separate problem.

I drained the gas today so that I can check the float and gauge.

I don't know about the high heat. I will double check the coolant level, although it looked fine a few days ago.

[borris120]

Check "Erratic fuel gauge tutorial by alleyoop" in the library under air,fuel, and carb. link ishttp://scooterdoc.proboards.com/index.cgi?board=intake&action=display&thread=7608 for a shortcut. That should address the fuel gauge.

[Bashan]

Two things on your heat problem. First, the fan is a backup and not designed to keep your bike completely cool. If it overheats while riding and air is moving over the radiator then you definitely have a problem. Second, your thermostat might be opening at the wrong temperature. Pull it and put it in a pan of water that you're heating on the stove. Put a thermometer in the water and see when it opens. Most of them are 180 but check your manual.

[vansmack2]

Bashan where did you get the brass float you used in this tutorial? scooterdoc.proboards.com/index.cgi?board=intake&action=display&thread=7608

I went to take my fuel sending unit out today and the float would not come out through the hole. I tried to wiggle it out and the float came off of the wire. I removed the tank to get the float out of it. I managed to get it out in pieces with a bit of work, and patience.

I am not sure if that float was bad and that was my problem, but I removed the sending unit from my parts 150, hooked up the battery and the gauge tested fine while moving the float arm on the sending unit.

The old unit seemed a bit loose on the rheostat (resistor part) where the contacts slide. I removed the retaining clip, squeezed it to make the hole smaller, reinstalled it, and tested that unit on the scooter. It seems to be working also, but is now missing the float from the wire since the float got destroyed.

I can get a new unit for $16.23 shipped from scooterdomain.com, so I think I will go that route.

Now I have to see what is going on with the high temp.

[vansmack2]

I tested my thermostat today, and it worked perfectly. I took a wire coat hanger, cut it up, and made a hanger to suspend my thermostat in a pan of water. I heated the water to about 180 degrees using a meat thermometer to test the temperature. The thermostat opened about this much ----- (may vary on your PC, but looks right on mine) Specs says it should open 3.4 - 4.5 mm, which it did. I will put the thermostat back in, refill the coolant, and burp the system good. Also my new fuel sensor/float should be here by Thursday.

I sure hope this solves all of my issues!

Below are pics of my procedure for the Honda 244cc clone. The board may use them as they see fit.

First you have to drain the coolant.


Remove any items in your way, like the r/r, and hoses.


Start disconnecting hoses, and the thermosensor wire.



Remove the thermostat housing. The bolts may be hard to get to.



It is removed time to test the thermostat.



I made a hanger to test my thermostat.



Reverse the procedure to put everything back together. Fill the coolant, and burp the system.

[Alleyoop]

Thank you Vansmack2, very nice how-to and very nice and clear pictures.
I copied them and downsized them so nobody has to scroll right and left.
Alleyoop

[jenningsjosh]

I went through same procedure on my bike.. EXACT same motor.. only thing that was different was my thermostat would not open... I ordered a whole new housing.. which came with thermostat, thermosensor, and the housing..(35 bux with shipping EBAY). FLUSHED my system tell it was clear and i was blue in face!! lol... then hooked it all back up! Temp is now FINE.. NEVER goes over half way mark now! I got all my advice--help-- and tips from right HERE... THANKS EVERYONE and hope your bike turns out just like mine!