Jog starting problems with good information...

[zacman]

I have a 1986 Jog that I just bought, only 567 miles on it. Seemed like it would be straight forward to get it working. It starts with carb cleaner and runs for a few seconds, starting with either the electric or kick start.

I have yet to be able to get it started on its own gas until about 5 mins ago. For whatever reason I thought putting my hand on the intake of the carburetor would be a good idea, well I did and the damn thing started!!! Wasn't able to duplicate it and a lot of fuel comes out on my hand.

Before this point I have checked the spark plug, works great though covered in a bunch of oil. Took the exhaust pipe off to see if that would help, cleaned the carburetor and all the jets and holes I could find, TWICE. drained the gas and added fresh, flushed the system, rebuilt the vacuum petcock. Messed with throttle cable tension, idle screw, not sure what is the problem...

PLEASE HELP!

[str8dum]

by checking, you mean replace the spark plug, correct? always start with a fresh plug when it doesnt start. Also, what kinda choke system does it have? electric or manual?

SO when it starts, you cant get it to idle even? I'd expect it to die if you hit the gas bc he engine is so cold.

Are there mods on the bike or is it stock?

[zacman]

The bike is stock. I checked the plug and tried putting a new plug in but the new plug doesn't seem to have as good of a spark. Starts right up with starting fluid on the old plug, doesn't on the new one.... Strange, both are gapped the same but the new one just has this crappy spark, same plug.

It only runs when I throttle it up, dies at idle. I actually just got it started and ran for about a minute, longest ever, I doubt there could be enough fuel in there to run that long, some new gas would have had to come from the fuel lines so things should be good there. Kept running as long as I kept giving it throttle.

I am now thinking there is a problem with the idle and choke on the carb. Its an automatic but the seal where it attaches to the carb is kinda *potty mouth**potty mouth**potty mouth**potty mouth*ty, could that be a problem? I screw it down real tight so I wouldn't think it could leak air. After it died I tried to start it again, nothing, until I opened the throttle a little and then it started back up.

I think I cleaned the carb pretty thoroughly, at least every jet I could find. Could be a choke issue but I tested it with a meter and I read somewhere that it needed to be less than 10 ohms and I was getting 5-6, never saw it move when I applied 12V to it though, not really sure how that part is supposed to work.

[zacman]

Okay, for anyone willing to add any more suggestions. I have gotten the bike running and it will idle now. I overlooked the pilot jet and drilled it out a little bigger. Also, I added a fuel filter before the petcock to make sure any of the crud in there doesn't foul the carb again. Now the problem is starting. If I start it by hand choking it, ie with my hand over the intake, it starts after a few cranks. Then it will run at any throttle position and idle, for 5 mins or more. Then it starts to rev up a bit and will die after another minute of rev'ing.

Also, I verified the choke is working, blowing through the airhole with and without 12v applied to it. Checked the intake manifold as well and saw that the reed valves are in good shape. Not sure what else to check.

[zacman]

Update: I put new tires and tubes on and took it for its first ride of its second life. I got it started the way I described before, hand choking, then put the air filter on and went for a ride.

After it warms up it won't idle, dies after 10 seconds of sitting or so. Starts right back up if I open the throttle a little. Makes me think its a choke problem even though I did verify that part works. Maybe I need to open the idle screw a little more since I adjusted it before the engine was warm?

I'd love some thoughts on the intial starting problem, using my hand and getting it covered in gas each time I was to use it might not be so nice.

Appreciate anything anyone has to say.

[Lennox]

did you clean the choke "curcuit" within the carb?

I also imagine that drilling the pilot is not such a good idea....

[zacman]

What do you mean clean the choke "circuit?" I guess I'll answer no. The holes from the intake to choke and then to the other side of the carb are all clear.

I didn't drill it much, only a little to make sure it wouldn't clog. It idles now and thats what the pilot jet does so I think its okay. Just doesn't idle warm...

[Zuma-Zuma]

Do a compression check. Your rings may be stuck form old oil (or something else). This would cause ALL of your problems. I don't mean putting your thumb over the hole either. Use a gauge, switch's off, throttle open all the way. Hopefully, you're over 100. Its possible that with all the fuel and spray, you're slowly looseing the rings, and slowly getting further and further.

[zacman]

If the compression is bad I'm F'ed right.... I'll try to find a compression guage.

[str8dum]

no, you just need new rings and possible a piston.

If you do replace the piston, you also need a new wrist pin bearing and C clips.

[zacman]

Thanks guys, I ordered a $20 compression guage and I'll report back in a week or so.

The good news is today I went to start the scooter and tried it with just the electric start, no hand choking or anything. It started right up, crazy!
Maybe running it for a couple miles is starting to get the carb and engine back in order.

The thought of rebuilding the engine is a little interesting to me, always wanted to try something like that...