JCL 150 just spits and sputters By deanie (Read 826 times)

[deanie]

I've been working on a JCL 150 for quite a while.  It had been sitting for years.  It's a 2007 with 770 miles on it....that's how long it has been sitting.  I changed all fuel lines and vacuum hoses, bypassed the charcoal canister which was cracked, installed a new carburetor, and installed new brakes.  It was running fine, but suddenly began to hesitate at the beginning of giving it full throttle, then catch up.   I couldn't find any vacuum leaks, so I made a very slight adjustment to the carburetor float (I thought maybe it was starving for fuel).  Now, when I give the gas, it really spits and sputters horribly.  I also noticed that the carburetor idle screw doesn't seem to make much of a difference at all.  Any suggestions on adjusting the carb float and idle screw?  Any other ideas as to what may be wrong?  I guess I'm not entirely convinced that it's a fuel issue.  Thanks.

[solymar]

Sounds like you eliminated any vacuum leak possibility so check in the library section, in the Air, Fuel & Carb tab is a post by Allyoop about carb flooding that shows how to adjust the float. I’d also check the jets to make sure their not blocked or partially blocked. I would also adjust the air/fuel screw to make sure that is set correctly.

Solymar

[cyborg]

Id bet a good sum on the jets picked up a bit of dirt,,,or the fuel tank may have had some goo in the bottom that's making hits way into the fuel system,,,does the exhaust smell funky? When it's running I mean

[deanie]

I'll check the carb float level and idle speed settings, as well as gas tank gunk tomorrow....I'll report back as soon as I can.

[deanie]

Well, I adjusted the idle mixture screw by turning it in all the way, and backing it out 2 1/2 turns as a starting point, and adjusted it from there.  I added more fuel (it really doesn't like to run on less than 1/4 tank or so) and added a tiny bit of Marvel's Mystery Oil.  Between those 2 simple things, it is running better than ever before.

I'll be changing the oil, soon.  What type of engine oil do these scooters use, and approximately how much?  Is there a drain plug?  Also, is there any transmission or gear oil that I would need to check or change?  Sorry for the constant questions....  Thanks for your help and patience!

[solymar]

Glad it’s running better!

The drain plug is basically under the dipstick on the bottom of the motor. Which oil is a debatable subject. Some people use full synthetic, some use conventional oil & some use diesel oil. I personally use Valvoline 4stroke motorcycle oil 10w-40 that I can get at Walmart for pretty cheap...something like $4.25 a quart. It takes less than a quart to do a oil change.

Gear oil is the 80w-90 or 75w-90 types usually, and can be found in both conventional & synthetic.

Just above this section is Rich’s scooter doc manual, it a lot about which oils to use from some of the pro’s. It’s a good read even if your set on what brand/type of oils you’re gonna use.

Solymar

[deanie]

Thanks, so much, for the great information!  One more question, if it's ok......where is the drain and cap to drain and add gear oil?  Thanks, again, for the help!

[solymar]

The drain and fill bolts are on the left side of the bike, pretty much at the back of the cvt cover. The fill is at about the midway point just behind the cover. The drain is nearly straight down, below the cover. Both are 10mm bolts (at least on mine they are).

Solymar

[deanie]

Thanks, so much, for the help!

[czmdiver]

Here ya gone that fill and level check bolt is at the rear lower. you can se the bolt and the drain is underneath it.

[deanie]

Well, oils have been changed.   The motor oil was disgusting....probably never been changed.   I started it up, and it up, and the rpm's were much higher than before.  I just figured that it was because the oil was so thick before I changed it.  I adjusted the idle speed, and took it for a spin.   Once again, it was spitting and sputtering like before.  I didn't have time to fool with it.  This morning, I had planned to open it up again to check things out.  Before doing that, I removed the gas cap, thinking that maybe it was clogged.  I cleaned it up, and blew through the outer hole with success, and I put it back on and started it up. I gave it a quick ride down the street, and it rode well.  I'll run it again tomorrow, but these days, it just seems to start spitting and sputtering without notice.  I only ride it down the street and back each day, nothing more.  I bought it as a favor to a friend who was in a bind, and don't plan on keeping it.  I don't want to sell it, however, if it's not running well.  Any idea of what I could check out if it starts acting up, again?

[solymar]

When is it having problems? Meaning, how far have you twisted the throttle...1/4 way, 1/2 way 3/4 or full open?

Solymar

[jrsride2002]

I also had similar symptoms from one of my dirt bikes. For me, it was a dead/dying battery. Bought a new one, ran brand new. Maybe your scooters battery?? Free testing at your local auto parts store.

Just a thought from one of my experiences,
~ Junior

[deanie]

The battery is a few months old, but I'll charge it today, just to make sure that it's fully charged. As for the throttle, if it's running well, it's fine at all throttle levels, and if it decides to spit and sputter, it idles great, but acts up on full throttle, all the way down to about 1/4 throttle. At that level, it can putt along without issue. I'm wondering if I could maybe have some trash in the tank. The first thing I did upon receiving the bike was to completely empty the tank, and it seemed to be clean, although the gas that was in it was probably several years old. Or maybe I should try completely cleaning the original carburetor and putting it back on. The carburetor I have on there now is new, but was fairly inexpensive.

[solymar]

It’s possible that the fuel pump/petcock is failing or the new carb isn’t jetted right. I’d read this post by Allyoop & see if any of this helps scooterdoc.proboards.com/thread/8628/motor-sounds-tells .

If none of that helps, it’s also possible that the issue could be something ignition related. If you haven’t already, replace the spark plug with a new NGK one. If you already have or if that doesn’t help you might need to change the ignition coil and/or the cdi.

Hopefully one of these will fix you issue. Let us know what happens.

Solymar