96 gsx WONT REV above idle

[mscphillips]

Hi guys
my 96 gsx (ive just baught it) wnt rev above idle (i was silly and didnt check it for reving when i baught it)

so far i have
- removed carbs and cleaned
- replaced grey fuel lines
- removed and cleaned raves (btw the oring on these was bigger than the shaft is that normal?)
- set mixture screws
- replaced spark plugs
- checked to see if it runs on res


it runs on premix, the hose to oil pump is blocked off. and the tank was empty that feeds the rotory valve but i filled it up.
also when you hold it WOT it blows fumes out the MAG side carb.

any ideas would be great thanks.

 

[timmyboy76]

quote... it runs on premix, the hose to oil pump is blocked off. and the tank was empty that feeds the rotory valve but i filled it up.
also when you hold it WOT it blows fumes out the MAG side carb.

Think you need to pull the carbs back off, along with the intake manifold, to inspect the rotary valve plate. Make sure it turns while ur turning the pto..(under the grey shield). With run'n NO OIL, the brass gear, located in the rv assy, needs a "oil bath" and without it, it'll strip.

 

[mscphillips]

re

just had the carbs of went throught them again everything appears good

took the grey cover off and when u spin the pto the valve spins with it, it looks like is in good cond, doesnt move arount etc. these carbs dont have accelerator pumps do they?

 

[timmyboy76]

no xcellerator

have the lsa (low speed adjusters) set at 1, highs (have black caps on them) at 0

Make sure the RV is timed correctly...147*/65*

Its ok to run premix/blocking off oil pump, BUT you need oil in resivor to continue to feed the RV assy...

 

[mscphillips]

re

ok have checked both , still the same
(PS thanks for helping tim)

its like as soon as you crack the throttle above it drops a cylinder it just goes mmp mmp mmp mmp and blows a shitload of blue/white smoke and if you squeeze throttle to flatt out it ocasionally backfires out the carb

??? its starting to stress me ps tach also doesnt work so i couldnt tel yu what its revving at.

 

[mscphillips]

re

been fidling checking all day and for about 5 minutes it came good and was revving out nice and i was holding it full noise then it dropped back to around 4000 and started to miss, then shot back upto full noise now its back where ut was not revving and blowing heaps of smoke


im thinking its and electrical problem as the plugs are wet as how do u test coil and leads etc

 

[jayzz1]

gsx wont rev & back fires

if all is ok with carbs , remove flywheel cover and check magneto for tightness and any sign of flogging, and hitting of pick up coil, this fires the ignition for timing of spark. if this is loose or become adrift timing is unstable.

 

[mscphillips]

re

im just about to go check that thanks

i just noticed if u hold it full throttle fule fumes puff out of the mag side carb (air box is off) what would this indicate?? no spark in that cylinder??

 

[timmyboy76]

hit'n the rev limiter. you'll hit it, out of water, at 1/2 throttle...think thats what ur experiencing.

 

[mscphillips]

re

ok everything was tight, signs of rust on the coil pickup, is there a way to test it?

 

[jayzz1]

gsx wont rev

the pick up coil is located on the mag side of engine on flywheel cover i'm not sure if can take covers off while engine in craft, there should be no rust or foreign material specially metal as this causes false pick ups, also note the tip should show signs of no impact, is the magneto tight on the fly wheel check this for signs of looseness, both spark plugs fire at the same time they are in series with the secondary coil, check for spark on each, if this is fine and you are sure carbs are o.k, check crank shaft for mis alignment and rotary timing 146 op 64 degrees closing.

 

[mscphillips]

re

after pulling the carbs down again and comparing to the manual i found tht part number 54 in the carby diagram attatched is missing??

(sorry not real good with computers)

what does it do?


what would make fuel spit out the top of the MAG carby like a puff under fool throttle???

rave vavle has about 1mm backlash in gears.

 

[mscphillips]

re

parts diagram.

 

[jayzz1]

gsx wont go

part no 54 on carb diagram is the fuel diaphragm this should be clear, Note this part is essential for pump pressure and operation, the pulse line from engine pulses this to pump fuel, If you dont have this part u will need it!

 

[mscphillips]

re

im off to pull them apart now and ordered parts.\

i will keep you posted with findings thankyou. ps had a thaught it maybe the high side of stator

 

[mscphillips]

re

apon further investigation the gaskett isnt missing i just missread the pic, the black gaskett is stuck to the housing, my bad.

any other ideas, it intermittantly revs right out im really thinking its electrical any ideas guys??