Venturian1
Member
This ski was given to a friend, because the previous owner could not get it to run right. I thought, no problem, bring it over, that was three weeks ago, and I'm still not getting it right.
I did all the usual stuff with the fuel system, cleaned out tank, new filter, all hoses black and flexible, tested fuel valve, check valves, rebuilt carbs with OEM kits, set pop-offs psi to max (43 psi), new check valves in fuel pump, blew brake parts cleaner through low speed holes, it came out in three places in carb bore, new base gaskets, mounted them on a spare rotary valve cover to check throttle positions to be even, etc,
So, I re-installed carbs, it fires right up, revs up right after starting, (once anyway but gets worse and worse the longer it runs, to the point where it won't rev up at all. Took carbs back off and set pop-offs at lowest setting (23 psi) no change. The injection rate was set way too high, so I thought its probably oily in the pipe, and it was,
The water regulator valve on the water box I'm not sure of tho. The spring inside is awfully stiff, would require a lot of exhaust pressure to overcome it to shut off the water being injected into the tuned pipe, its much stiffer than the rave springs, but this rev problem exists with or without water, although It idles fine, (at 3,000 rpm) until I turn the water hose on, and immediately i notice a change in sound and rpm drops. Now it sounds like its struggling, that changes to desperately struggling or only running on one cylinder, and a knocking sound starts. Shut off water, try to rev it to expel residual water, and it won't rev at all. I'm beginning to think its a timing issue, but then why would it rev up fine (but just one time) right after starting?
The CDI module is new, I swapped out the whole rear electric box with a known good one, no change. I gravity fed the carb with a gas can tied to the handle bars thinking there was blockage in a fuel hose or fuel valve, nothing changes. Maybe someone put 10-40 in the oil reservoir? I removed the oil tank, cleaned it out, sucked all the oil out of the rotary valve shaft cavity, and the inj pump, replaced the oil filter, replaced the tiny injection hoses so I could see air bubbles, Idled it on premix until no more bubbles, and it still does the same old stuff, no revs. I'm thinking crank seals now. time for a leak test. or magneto/pickup coil, or partially sheared flywheel key. Plugs are new, spark is bright, compression is over 150 on both. Any ideas or suggestions anybody? Thanks for taking the time to read this!
I did all the usual stuff with the fuel system, cleaned out tank, new filter, all hoses black and flexible, tested fuel valve, check valves, rebuilt carbs with OEM kits, set pop-offs psi to max (43 psi), new check valves in fuel pump, blew brake parts cleaner through low speed holes, it came out in three places in carb bore, new base gaskets, mounted them on a spare rotary valve cover to check throttle positions to be even, etc,
So, I re-installed carbs, it fires right up, revs up right after starting, (once anyway but gets worse and worse the longer it runs, to the point where it won't rev up at all. Took carbs back off and set pop-offs at lowest setting (23 psi) no change. The injection rate was set way too high, so I thought its probably oily in the pipe, and it was,
The water regulator valve on the water box I'm not sure of tho. The spring inside is awfully stiff, would require a lot of exhaust pressure to overcome it to shut off the water being injected into the tuned pipe, its much stiffer than the rave springs, but this rev problem exists with or without water, although It idles fine, (at 3,000 rpm) until I turn the water hose on, and immediately i notice a change in sound and rpm drops. Now it sounds like its struggling, that changes to desperately struggling or only running on one cylinder, and a knocking sound starts. Shut off water, try to rev it to expel residual water, and it won't rev at all. I'm beginning to think its a timing issue, but then why would it rev up fine (but just one time) right after starting?
The CDI module is new, I swapped out the whole rear electric box with a known good one, no change. I gravity fed the carb with a gas can tied to the handle bars thinking there was blockage in a fuel hose or fuel valve, nothing changes. Maybe someone put 10-40 in the oil reservoir? I removed the oil tank, cleaned it out, sucked all the oil out of the rotary valve shaft cavity, and the inj pump, replaced the oil filter, replaced the tiny injection hoses so I could see air bubbles, Idled it on premix until no more bubbles, and it still does the same old stuff, no revs. I'm thinking crank seals now. time for a leak test. or magneto/pickup coil, or partially sheared flywheel key. Plugs are new, spark is bright, compression is over 150 on both. Any ideas or suggestions anybody? Thanks for taking the time to read this!
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