The fuel gauge does not work on jonway yy250t alias Roketa By miky6719 (Read 4,370 times)

[miky6719]

I tested the connections and now something happens, if I press the probe then the meter starts to level the score correctly, I saw in another thread that you have changed the probe as in the picture but I do not understand how and what has been done.

imageshack.com/a/img811/1803/paiw.jpg

There is a picture where you can see better the change?



Thanks at all

[Bashan]

The blue/white and yellow/white send varying voltages that change as the variable resistor changes with the float:

When the float is down (empty} the ohms reading on the Y/W to ground will be high:

[

when the float moves up the resistance reduces sending more voltage on that wire:

Conversely, when the float is up the blue white will have high resistance:

but when down the resistance drops dramatically:

It is the changing voltage on these wires that pull the needle back and forth via magnetic forces. The voltages on the wires change but the net voltage entering the gauge remains essentially the same. Further questions are welcome as I had a great write up on this but can't find it!

[Alleyoop]

If he presses on the swivel part plate and it then registers then the plate is loose and the tiny fingers in back of the plate are not making good contact with the resistor plate on the plastic. So he just needs to tighten it up not so much to cause it to bind but enough for the tiny contacts to scrap against the resistor plate.

That is what happened to mine it was loose and sometimes the brush's would make contact and sometimes not so my gauge was all over the place. Sometimes it would register empty when it was full. They have a push on lock washer to hold the wire tight against the plate what I did was cut out some of the plastic around where the wire comes out and I replaced the push on lock washer with a small brass collar that you tighten with a set screw like the picture he put up that is my float.
Alleyoop

[miky6719]

sorry for the many questions but I'm using google translator to understand your answers. You mean to replace this:

with this:



it's  right?



Thanks!!!!!

[Alleyoop]

Yes, that is what I did. You can see it in the picture you put up THAT IS MY FLOAT SENSOR I had the same problem.
Alleyoop

[Bashan]

I'm glad my involved electrical diagnostic post helped....you know...guru....somebody said guru...I think they did. Gooooo-roooooooo. Guru, it means.....forget it.

What he could do Alley is set the ohms test up and move the float arm around on each of the tests and see if it goes OL which would mean he lost the circuit entirely. In that case the variable resistor is bad and he would need a new sensing unit. The Great Bashan, Guru. Alley called me the great Bashan....blame him. I'm anxious to see what Google translator does with this. Hey translator....bite me. Guru Bashan, the great and obnoxious.

[miky6719]

hello "The Great Bashan" I'm sorry but I saw only now your detailed answer, thank you, I can just the level sensor and will test the resistance as you did.

Thanks at all!!!!!  

[Bashan]

He actually thinks I'm "The Great Bashan"! snif. Hey....what about guru?..I didn't hear guru!! Alley!....tell them!

[miky6719]

Update .. I have not found the small brass collar, so I'm thinking of using an electric clamp the take off the plastic cover and use the terminal as if it were the small brass collar.

imageshack.com/a/img580/997/wdh4.jpg

imageshack.com/a/img838/9450/h54d.jpg

One other question, the rubber seal between the tank and the probe is to be replaced, it seems a bit squashed, I can replace it with a gasket for water pipes or gasoline may damage it?

Thanks

Bye

[gatordawg]

Same scooter, same issue I think. Just bought a 2007 built Roketa 250 clone used w 3300mi and the previous owner neglected to mention that it runs out of fuel at 1/4 tank (or maybe it broke after I bought it 2 weeks ago) . Arrgg. My 2mi walk on a high speed rural hwy gave me time to reflect on how much fun this scooter might be.

So, I found this thread and thought I'd just pop out my sender and I started rooting it out. Holy carp whatta beast to get to. It's a front tank wedged in tight behind the radiator/fan and under the backbone tube, surrounded by the outer rails, backed up by the mid-frame uprights. The outer plastic panels were unreal enough to jockey loose but even when those are off it now looks like the only way to remove the tank is out through the front after removing the rad/fan. Clearance on top of the tank is about 1/4".

• At this point I'm committed (or should be) so, any sage advice on what I absolutely have to remove to get that sender out of the tank?
  

• Can it be tilted enough after removing the side mounting brackets (of course one of which has an impossibly stripped bolt) or will the whole radiator need to go?
• If the float is shot, where/how can it be found?
• It restarted after putting 1/2gal in the tank and ran well so I'm feeling pretty confident it simply ran out still showing 1/4tank, but maybe it's something else that's intermittent?
  

Here's a couple pics of what I have. Thanks for any good advice. Bad advice,......not so much. Mike

PS, that collett type stopper shown above is easily found at any hobby store. look for an RC plane control rod adjuster type connector.

[gatordawg]

Pics of scoot, tank, sender:

[cyborg]

Mar 20, 2014 8:53:36 GMT -6 Bashan said:

He actually thinks I'm "The Great Bashan"! snif. Hey....what about guru?..I didn't hear guru!! Alley!....tell them!

Those darn translation programs Rich,, it actually reads Gorganzola ,,,,, ppphhhtttttt guru oh brother,,, lol

[gatordawg]

Here's a follow up that might be helpful.

I found the room to actually get the whole unit up and out of the tank last night without a total tear down to remove the tank. Hoo-rah.

For the sake of the next guy: After siphoning the tank nearly dry, removing the fuel and overflow tank lids, I loosened the two lower side skirts, removed the plastic center cover housing with the foot rests, removed the rt side tank support bar, and tank mounting bolts. Then slid the tank back as far as possible and tilted it to the rt which gave me barely enough room to twist the sender retainer clip and barely get the whole sender assembly out of the tank.

Luckily the sender and float looked perfect. My issue ended up being a sticky sender float rod at the pivot due to the circular pivot clip being pressed down a bit too far causing it to bind/stick. I slid a razor knife blade under it to back it up about .005 taking care to not allow too much slop. It now pivots up/down with ease and my faulty gauge is fixed.

Hope this helps the next guy that finds this site. Mike