1987 jog wont idle

[nitrogary]

i picked up a 1987 jog/riva that ran perfect the evening i bought it...a few days later,it wouldn't start but was cranking fine. i have put a new air filter in it and cleaned the carb and reassembled. ive cleaned many carbs on scooters so hopefully i don't thing its my handwork here but ill let you guys decide).

when i took the carb off the oil injection line cracked and ive replaced that with a new one, put the cab back on and it started and idled a few seconds then died, it did this many times. feathering the throttle would allow me to get it running and revving but still would settle down in rpm then just die. after searching here on this forum i found a post that has a pic of my carb in it and the hose that is pointed to in the pic on mine is just open to the atmosphere and the main fuel inlet line has a straight connector on it but not a tee fitting like in this picture

scootdawg.proboards.com/index.cgi?action=downloadattachmentpage&board=discussion&thread=37812&post=370686

now in looking in this pic i see the line that comes out the top of the carb and heads up to what i see being called the "vacuum hose to tank"...on my scoot i don't see the part that this line connects to.

so , if on my carb this line is "open" could that be the source of my nonexistent idle ? and if so, what do i do to get this thing back to normal....i still cant figure out why it ran so good on the night i picked it up and now its a big boat anchor....

thanks for the help folks

[scootinbow]

If you replaced the oul line than you need oil in the motor until all of the air is out of the line pull the airbox off and pour 2stoke oil in the mouth of the carb it will suck it up and it does take awhile for it to get it all out.

[nitrogary]

scootinbow...so are you saying that my nonexistent idle is because there isnt any oil getting ingested yet or are you reminding me that the engine needs oil to survive. that said, are you talking about adding like a teaspoon or what ?

thanks for the reply, i totally didnt address the fact that im not getting a supply of oil to the engine since i put the new oil injector line on...do i need to prime it or something or will it eventually start to flow on its own

[yoshidawg]

Sometimes these types simply will not run without some type of air cleaner, it helps create vacuum for the fuel valve. Also if you've gotten a lot of carb cleaner past the carb it will take some running time to clear it all out.

[skuttadawg]

Did you bleed out the air in the oil line ? Maybe this can help you 49ccscoot.proboards.com/index.cgi?action=display&board=yamajog&thread=3151&page=1 Tried a new fuel filter ? Drain the old gas out and refill with fresh gas with a sip of Sea Foam will clean out the lines . How does the spark plug look ? A 2T they will get oil build up that can foul it and not fire as good just as worn the gap is too big . NGK iridium will fire better and not as likely to foul . A new spark plug can do wonders for just a few bucks . With it being an 1987 if the engine is original it may need new rings to restore compression if its low due to wear . A new fuel filter is around 3 dollars too . Check the intake manifold for cracks or holes which make it run bad . Sometimes a size up in a larger idle jet can help

[skuttadawg]

49ccscoot.proboards.com/index.cgi?board=yamajog&action=display&thread=425 and 49ccscoot.proboards.com/index.cgi?board=yamajog&action=display&thread=506 about a leak down tester

[nitrogary]

thanks for all the info, im going to go play with that oil line some more and get it primed....i really appreciate the help as i might have ruined it if i kept running it like i was....also one of my original questions hasnt been addressed yet and is still concerning me. what or where does the line coming out the top of my carb that is smaller then the fuel line but bigger than the oil line,go to ?

on my original post i posted a link to a pic that has the line in question, i cannot find a open place for this line to attatch to and therefor its just sitting there on the carb acting like a breather on my carb, in the picture however it appears to be attatched to something under the tank above the carb...on my scoot i dont have anything like this. furthermore, on that pic there is a TEE in the fuel line and on my fuel line that is not there but is now just a connector fitting like perhaps the tee was removed and this two ended barbed fitting used to rejoin the two fuel lines back together....any comments ?

[skuttadawg]

Does it have a pecock or pump ? Try this run the air/fuel screw all the way in then back it up 2.5 turns of the screw and see how it does . Let it idle and turn it 1/8th of a turn a time or two and see if the idle changes , if so go up a size in idle jet