[Sylvester]

I know this is a well beaten subject, but I am in need of some additional technical information. The shop manuals are very vague with regards to the setting of the red adjuster on the cap and the proper output of the regulator other than "The water flow regulator should deliver 0.4 gallons per minute at maximum engine speed. There is no mention of where this water is being delivered to at that rate. Is it being delivered to inlet of the elbow fitting on the pipe, or is this the flow rate out of the elbow fitting and into the pipe? Since "the elbow fitting has a calibrated inside diameter to optimize water flow in tuned pipe."

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[redroses]

Given the lack of specs, I went out and did some on the water testing along with bench testing. The results for two different regulators on two different skis are nearly identical which seems to be good, except I am measuring about 0.8 gallons per minute from the hose end where it would connect to the elbow fitting on the pipe. If the value was close to the 0.4 I wouldn't be too concerned, but at double the value I am wondering what the deal is. I am doubtful that I have two bad regulators and instead I am thinking the manual is incorrect with the 0.4 value. Adding the the elbow fitting with the "calibrated inside diameter" I see a reduction in flow of about 0.1 gallons per minute, still way off from 0.4 gpm. [links]

[Grant]

I have also read several places, this forum included, that state the regulator operates in such a way that I should see a decrease in flow of water at higher engine speed. I do not see a decrease, instead I see a steady increase in flow from 1500 rpm to 5700 rpm and then the flow holds steady from 5700 rpm to 6780 rpm. If the regulator was not present, I would expect the flow to increase at the same rate all the way to 6780 as it does form 1500 to 5700 instead of flat lining.

[maddox1085]

[weed]

Still surging after replacing the rectifier

[harley4noble]

Since you went to pre-mix. you did leave the oil hooked to the rotary valve, and gears. right?? (just checking) here

[bitwaffle]

good for you. most people come here to bitch about non-running skis. Nice to hear that you got it running. [links]

[reQunix]

Hey, haven't been on in a while. No real problems to discuss. Just hadn't used the ski in a few months due to the colder weather. I took it out 2 weeks ago and it seemed to run fine. Took it out again last weekend and it ran for maybe 3 minutes before it acted like it had a fuel clog. I checked the fuel filter, cleaned it an reinstalled along with 2 new plugs. Still ran terrible so I went home. Checked the fuel valve, it's new anyway, so are the fuel lines. Took the carbs off and opened them up and inspected them. No obvious signs of a clog but cleaned the inline filters and scraped out any noticable corrosion, cleaned the jets and put everything back together. Runs fine now! I figured now was a good time to install a primer kit, so I put the plunger under the handlebars where the choke cable was. I also installed an oil block off kit since I was running premix and had the pump disconnected. Now everything is nice and clean looking. I also installed an extra inline fuel filter just before the carbs as a back up! I'm ready to ride.

[Thor]

good for you. most people come here to bitch about non-running skis. Nice to hear that you got it running. more

[riX]

Since you went to pre-mix. you did leave the oil hooked to the rotary valve, and gears. right?? (just checking)

[thomascaulk]

Sorry, i should have said that earlier. [links]

[hauns]

Turning it out will cut off the water sooner, while tightening it will allow water to remain flowing at a higher RPM.

[schlow22]

Thanks for the advice. Although the analogy was a bit flawed, but I got what you're trying to say. (no one drives around on a rim, unless it's a desperate attempt to avoid the law man)

[swinewine]

Here's where I was coming from, If my water pump failed, I may eliminate the mechanical pump and go with an electric one.

[enoxice]

yes, replace the diagram, it's a common failure, the metal clip pokes a hole in the rubber piece.

[BlackEye]

why. would you eliminate it? when you blow a tire, do you just say f_ck it and drive off?

[vorton]

The boat came with one SBT engine with just a few hours on it and one blown one. I replaced the bad one with a matching 787 from SBT. The boat started and ran, but it had serious cavitation issues, so I rebuilt both pumps with new impellors. First outing two weeks ago, it ran like a champ. Came out of the water great, topped out great - no issues until the very end of the day when it started to bog down and wouldn't go above 4000 or so. Figured I fouled the plugs or something and headed back to the ramp. Put new plugs in it and tried again. Same thing, bogs down and neither motor will go past 5000, however, it did rev up and plane out for a short distance. But, as soon as I throttled down and tried to take off again, I was back to 5000 and plowing. Plugs are very wet when I look at them. It doesn't appear to be over-oily, so I'm confident that the oil system and fuel delivery is fine. When they are running at 5000, I can throttle back from full to 2/3 before they start responding, so I'm pretty sure at WOT, the wet plugs are from the excess fuel.

[didiertomas2385]

So, the only thing I can see that would prevent ONE engine from running right would be the RAVE valve on the starboard engine. For the life of me, I cannot figure out what is preventing the other one from going past 5000 and why this happened rather suddenly. here

[audiogadgets]

Second thing I found was the metal band around the bellows in the opposing engines water pressure regulator was missing the screw and was not compressing. I located the screw in the bottom of the valve and put it back together. Again, obviously an issue, but I'm questioning if that would cause any real issues as the bellows and spring are fine. more

[destine]

My top rpm now is around 6800 in the water. Is it safe to adjust this and get the rpms up a little for a little more top-end speed? more

[Poorboy]

I have read the manual (so don't cut and paste that for me) but do not quite understand the theory of this adjustment. [links]

[cliff]

You can experiment with it. If you turn it all the way in, you will get better bottom end. If you turn it out, better top end. I've adjusted them either way for customers.

[jaymac407]

By adjusting the water regulator, you will notice a definite change in top RPM and bottom end acceleration.