'screwed up big time! (petcock/carbs) - Kawasaki Vulcan 750 Forum : Kawasaki VN750 Forums
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post #1 of 4 (permalink) Old 10-29-2010, 01:37 AM Thread Starter
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'screwed up big time! (petcock/carbs)


Last edited by FlacoLove; 03-25-2013 at 11:38 PM.
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post #2 of 4 (permalink) Old 10-29-2010, 01:54 AM
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Originally Posted by FlacoLove View Post
Aw man! My poor baby; what have I done to you?!!! "whaaa..." Last week my petcock started leaking (88 VN750) so as I'm presently awaiting ebay bids for one, I did the most stupid thing and rebuilt it to work temporarily with... Hi-temp gasket sealant. Aside from being extremely careful from assuring none would spill or mix in with any gas passages, I guess some got through. Two days ago I dropped a minute amount of STP carb cleaner into quarter tank, filled it with 87 oct and took her on the highway to test my new tires. After about 30 miles I noticed high revs at stops "and no more pops"... 'didn't think much of the no pops as I've just coastered but the high revs? hmmm... My bike sounded AWSOME!!! Today, I stopped at Straus for items (again high revs at stops) and when I went to turn her back on, she'd crank like crazy but wouldn't start. It was after awhile I gave it full throttle and she slowly came to life (minus who knows how much batt power consumed in the process); I head to work worried. At work, I turn her off, restart and nearly kill the batt; I smell gas... I look and there is gas seeping out of the plugged vac port of the rear carb (plugged because I've got rid of the um... (vacuum switch gizmo due to coasters). Gas was squeezing through the crude plug I had in there, coupled with gas seeping from the boot that goes from that rear carb into the engine. (I hope you guys are following this; I'm in pain over here). During work, I drain the... I guess it was the bowl, (it's the screw you turn to check the um.. you put a hose; turn screw; gas comes out; right under the decel diaphram thingie) anyway, I drained all I could; sprayed carb cleaner w/straw into vac port and blew & sucked with hose. After 7 hour shift and lots of praying, I started her up and had to throttle her ALL THE WAY! But she came on. Still high revs but no over leaks; I'm home.

My conclusion? (and correct me if I'm wrong) That STP (which contains partial jet fuel) burn through the sealant (which already had rubberized) and traveled the same passage as the gas; and found it's way to the intricate parts of the float bowl mechanism's (which I know NOTHING about yet) and who knows what else, and now my baby is sick. Some input here please? Yes, my girl's been rejetted months ago and never had starting issues, hot or cold. Also, even though my batt. cranks my bike well, it has taken a tremendous beating today. (not OEM) should I give her a charge?
Yeah a charge would do it good and sounds like you have a needle Valve sticking,remove the fuel hose going to that carb and put a longer piece of hose on it and blow through it ,open the drain for that bowl and spray some Gumout through the hose and maybe it will was out whatever is stuck out the bottom of the carb.If that doesn't work you'l have to pull them out and clean and check them,you may have a damaged needle valve on your float assembly.It is flooding and the petcock may have started your problem ,make sure it is not letting gas flow through it with the engine off.

If you see it on my bike I did it
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post #3 of 4 (permalink) Old 10-29-2010, 11:04 PM Thread Starter
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Last edited by FlacoLove; 03-25-2013 at 11:41 PM.
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post #4 of 4 (permalink) Old 10-29-2010, 11:23 PM
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I was having those troubles. The battery troubles went away when I got an AGM battery. The other troubles, were because my petcock was leaking. Not externally, but internally, it was letting fuel pass even if the engine was off, so everything flooded and it was really hard to start the bike, had to use full throttle like you and even then, there was no guarantee.

A good working petcock should help you and the AGM battery is definitely a GREAT investment.
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