Roketa MC-62-250 Starting issue... again By bdplayer81 (Read 4,235 times)

[bdplayer81]

I'm having trouble getting my scooter to start on a regular basis. When I try to start it the starter spins and I can hear some popping but it won't fire up. I can smell gas so it's getting gas. I have also replaced the battery, had the CDI changed, and had the valves adjusted. (All done by a mechanic by the way.) But still no luck. The only time I've been able to get it to fire up is after the battery has been fully charged. It will run and start fine but the next day it wont fire unless the battery has been given more juice. It has happened with the old battery and the new so that doesn't appear to be the problem. I have tested the voltage while under load and it is good. I was hoping someone might have a suggestion for something else to try. Thanks in advance.

[Alleyoop]

If you hear popping that means to much gas, so next time before you go to start it take the plug out and crank it over just a couple of times and see if gas shots out of the plug hole. It could be fuel is dripping down into the intake after you shut it off and trying to compress a lot fuel sitting there will need a lot of power to crank it over.
Alleyoop

[Bashan]

You may have a bad blocking diode. If it's leaking it'll run the battery down overnight and you won't have enough juice to start the bike. They look like a smaller version of a rectifier. Here's an example of one on a CF Moto clone but they all look similar:

This diagram is off of the Roketa site and you can see the diode as the small triangle up by the R/R:

I used that diagram, among other references, to make this hi-res version in which you can plainly see the diode:

There's a couple tests you can run for this. One involves putting your multimeter in series with the battery like this:

Don't worry if you hook it up backwards, it will just read negative mAs. Anything over 10 mAs is very suspicious for a bad blocking diode but it could also be in the rectifier on this test. This test measures leakage on the entire electrical system because you're testing right on the battery cable.

To test the blocking diode separately unplug it from it's harness. Then set your multi to diode testing and insert the probes into the diode plug both ways. One way you should get a small voltage as the diode lets the multi's small test voltage through. Then, when you switch the probes you should get zero voltage as the diode blocks the electrons:

If you get a voltage both ways you have a bad blocking diode and it must be replaced:

Bashan

[jetram123]

I had the same problem on my YY250T which is probably the same bike......and I had to take the whole right side off by foot plates and found that I had a crimped hose on the gas filter. Spread out the spring that covered the hose and that starting problem went away. I do believe they have an electric fuel pump.....so check it out and it might be your problem.

[bdplayer81]

Thanks guys. I printed out your suggestions and gave them to the guy working on it. Hopefully I'll hear back sometime this week if he figured out the problem.

[speedracer]

No one mentioned the stator at all. Since he can only start it after the battery has been charged it could be his stator isn't charging the battery. I would test the volts on the battery when the engine is running and see what it measures before removing the entire rear plastic panels and trunk.

[bdplayer81]

Alleyoop - Any idea what would be causing too much gas to fall into the intake when it's sitting and not running? I'm curious of how to fix that problme. I haven't heard from the guy working on it in a while and he's the second guy to look at it. The first one told me, "It just starts hard." Which I thought was a joke. In any case I'm about ready to ask for it back and see if I can figure it out on my own.

[Alleyoop]

It could be the float and plunger not shutting off the Fuel inlet completely and the bowl overflows. The plunger may have crud on it or the rubber tip may be worn or damaged or the hole itself may have crud and the rubber plunger not sealing or the Float may be set to low. Another thing next time check the VACUUM line connected to the INTAKE going to the PETCOCK or fuel pump and see if it is WET. It the Vacuum line is wet you would need a new Petcock or Fuel pump whichever one you have.
Alleyoop

[bdplayer81]

Still not results from the mechanic working on the bike. He's had it since April now. I've given him all the information you guys have provided for me and he's not been able to get any results. Apparently they haven't been able to get it started in more than a couple weeks. I guess it's becoming nothing more than a paper weight. I appreciate the input though! Hopefully we'll have a result before the riding season is over.

[bhinch]

Pick up your scoot and this forum will help you fix it and get to riding.

[Alleyoop]

I agree with BHINCH, SINCE APRIL HOLY crap, they are not very good mechanics take the sucker back and if you have a little bit of mechanical ability even if you don't we can tell you and show you what to do. If my scoot was in a shop more than two weeks I would be screaming at them, I think they are just oil and spark plug changers to tell you the truth. That is what they do they take the easy oil changes and items like that first and leave any hard stuff on the side because they DO NOT KNOW HOW TO DIAGNOSE a problem they are good at replaceing parts and changing oil.
Alleyoop

[richardthescooter2]

I also agree with bhinch & alleyoop, learn how to work on your own scoot, these guy's here are great and know what their talking about, they can show you how to fix any problem you have concering scoots. I can't count the times that I got help and here with my scoot. (this is a great forum)

[bdplayer81]

I'm going to agree with you guys. I took it to him because he had done right by my Dad a couple times they needed their scooter fixed. I have had the same problem with the scoot for a while and I figured he would be able to get it fixed. He said he's going to try one more thing and I told him if that doesn't work to put it back together and I'll come pick it up. He wants me to pay him $700 if his last idea works but I can tell you that won't be happening. From now on I'll be getting my scooter advice from you guys and working on it myself. I will let you know when I have it back and I can start from scratch. Assuming he hasn't made it worse... Thanks again!

[Alleyoop]

WOW!! $700.00 talk about a rip off, you can buy a new 150 for that price. That is what the problem is with shops they do not know how to diagnose and rack up hours just fiddling around with it and they usually leave it in worse condition. One thing they usually do is NOT tighten things up and or leave screws out because they lost the damn things. You can tell what kind of shop it is by how clean and organizied it is. If crap is laying all over the place do not take it there.
Alleyoop

[bdplayer81]

Well, I got the scooter back. It's in pieces but its mostly just the body parts which will make it easy for me to work on it. I put the air cleaner (which they managed to break) back in and the air hose. The only thing I can't figure out is where the part in the picture goes. Once I have it back in order then I'll get on trying to figure out what's wrong with it. Thanks guys!

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