How good is a Polaris SL780

[ajthegreatone]

I was just wondering just how good of a machine is a 1997 Polaris SL 780. I just bought this machine about two months ago. It runs great for now. I was just wondering if the is anything about this machine that is somthing to look out for or is there something I sould do to it for preventive maintance. How is the fugi engine in this thing, are they any good? And do I have to worry about any carberation problems with this waverunner. I read in here that if gas sits in the carbs for more than 3 months you should have them rebuilt is that true. my carbs seem to work great.

[WATERCRAFTSERVICES]

Re: How good is a Polaris SL780

The 780 Is A Generally Reliable Engine If Maintaince Is Kept Up. They Did Not Have The Fuel Pump Issues That The 650-750 Motors Had. 3 Month Old Fuel Is Ok If A Fuel Stabilizer Was Added. If Not Then It Will Be Better To Change With Fresh Fuel. Fuel Tends To Loose Its Charastictics Over Time Such As Octane Rating. Low Octane Fuel Will Cause Detonating And Harm The Engine If Ran Long Enough. If In Doubt Change It Out. As Far As The Carbs If They Seem Responsive And Operating Properly Then Do A Plug Check After A Ride To Determine If It Is Burning Correctly. Also Clean The Fuel/water Seperator Sediment Bowl Before Taking It Out.

[Jamie in NY]

Re: How good is a Polaris SL780

I have an '96 SLT780. Never tweeked anything, just maintained it and drove it hard for many years. Last year the engine froze (piston #1). I think the oil pump gave out, so after installing a new SBT I took the pump off and switched to pre mix. You may want to do that now, just to preserve what's left of the motor. Pretty easy. SBT sells the kit.

The display on these things tend to go, especially if you roll the ski and leave the display submerged for any length of time. Displays are expensive, around $400, so if you flip the ski, roll it back asap.

Also had a problem with a cooling hose wearing thin and leaking into the ski. It is the hose that comes off the exhaust manifold way up front (under the oil tank) then immediately curls around and runs under the motor. The hose has a plastic shell (tie wraped on) that worked loose and the rubber hose started rubbing somewhere. Sprung a leak and nearly sank the ski out on the water. You may want to reach in and make sure the plastic shell is still protecting the hose.

Just a few more things, the float inside the "fuel level sending unit" that reports fuel level tends to get "water logged" and sink, giving false "low fuel" readings, which in turn causes the ski to switch to "limp home mode". Most folks by now have changed to a new and improved float, just something to be aware of.

Use a high quality marine grease and grease the drive shaft bearing regularly (like 2-3 times a summer). The grease fitting is inside the hull, near the back.

If your ski starts running "iradically" (for example, won't start, cuts out, runs great then runs bad, etc) the first thing to check are the wires inside the black electrical box. Unbolt the box, split open, and make sure all wires are firmly attached. You can disconnect each wire one at a time, clean up the terminals, then reattach with a dab diaelectric grease. Doing this has cleared up a few problems for me over the years.

Enjoy whats left of the season :)