running problems could be fuel?????

 

i have been given a 1990 fj1200 cv3 but it wont run right . it will idle ok
(thanks to new ngk plugs gapped to .85mm )but when i ride her for a mile
it will die then wont restart until 10 mins later.then it will go ok for a
mile then die (sometimes with a big backfire !!)etc etc etc... anyone had
a simalir problem ..any clues????

 

googoo73 wrote:

I don't have any experience with an FJ1200, but that's a classic description
of a plugged fuel tank vent.  If so, it's a pretty easy problem to either
rule out or fix.

 

sounds like you may be getting a lil extra fuel in the engine ,but is it
backfiring out the intake or the exhaust ,does it do it if you have it
parked and you run the rpms up or is it just under load,
is everything original or did someone put on an aftermarket part (have
seen this happen on different things ,replaced the aftermarket part with
a factory original part and they ran fine)
sometimes just because it fits doesnt mean it will work right.
But do all the easy and cheapest stuff first if the vent isnt your
culprit
GL

 

i've checked the vent and its fine i also tried to ride it with the cap
open but it does the same thing .it will idle loveley for 1-2 mins then
cutout dead wait 5-10 mins (with ignition off )and it will re-start first
press of the starter and idle spot on for 1-2 minutes .the backfire is
only when i try to fire straight up after it dies...i reckon its got to be
fuel derived as just before it cuts out it hiccups ala fuel starvation.the
pump seeems ok as it pressurises on turn on and pumps consitantly when not
pressurised (pipes off) . there is a good flow of fuel to the pump,and the
pipe to the carb is ok .the only query i have is when i blow/suck into the
carb it is restriceted is this correct (sorry i have limited knowledge of
carbs most of my other wheels have been injection)....pleeeesssseee help
i'm dying to take it for a good long cruise

 



I guess it could be the condenser across the points, (or a capacitor in the
ignition module),
going open/short circuit when warmed up...

Nick
up...