Variable exhaust valve cleaning Q.
I'm riding a '03 Polaris 700 SKS with the variable exhaust valves. My mpg is pretty bad. I have about 2000 miles on her and am wondering about pulling the exhaust valves on the front of the motor and cleaning them.
Any one have any advice or comments on how to do it and if it will help improve my mpg, please?!
She runs well, but I'll use 10 gals or so in 50-60 miles if i'm playing in the powder. Trail riding to the cabin (20 mph) and hauling a light load I will use 5 gallons for 25-30 mile trip, while my wifes XLT will burn about 1/2 that.
Also, is it wise to use the blue Loctite when reinstalling the exhaust valve screws as a friend had one of his screws on his machine back out and it siezed that cylinder?
What do you use to clean the valves without damaging them?
You'll find them coated in hard carbon. I scrape the stuff of carefully with a putty knife and utility knife. Some solvent will clean the sticky oil residue off. Be careful not to damage the bellows and have new gaskets in your hand before you start. Yes on Loctite. Blue is what I use. Don't over-tighten the bolts when you put the valves back on.
Will it improve your mileage? I can't say. Your mileage is similar to what I get. Hammer the throttle in the powder and your lucky to see 60 miles on a tank. The first thing I did with edge sleds was change to a clear tank. All snowmachines should have clear tanks so you can see what you have.
To piggyback on Mr Pid's advice, you should clean your exhaust valve guillotines every 500 miles or so, or at least every season. It's a good part of end-of-season maintenance.
I've got the same motor as you do bkmail, in an 03 RMK 700. I clean mine with oven cleaner and a scotchbrite pad. If you use a blade be carefull. 2002-2004 OEM exhaust guillotines are cadmium plated. For whatever reason you're not supposed to damage that coating.
Thanks for the advice and the heads up on the gasket and blue loctite. I'll work on it this days off and see how she performs.
Seal and Gasket remover.
I use Seal and Gasket remover to clean mine. Spray it on, wait 10 to 15 minutes and wipe them clean with no scrubbing or scrapping needed.
I'll second the powder riding, boondocking, and hill climbing eats the fuel. Also, 700's do not have the best reputation for fuel mizers. 60 miles on a tank in hard riding conditions is the norm. Back in the good 'ole days before $3.50 a gal. we didn't seem to mind. Now it hurts physically and financially to play.
Your help is appreciated
Thanks for the info. Also, thanks for the advice on your earlier post regarding choking off your sled in cold weather. I'm headed to the cabin this weekend and well give it a try.
On cleaninig the exhaust valves, you simply back out the two screws. Behind the plastic shroud are my reed valves and a spring, correct?
Are these the only pieces to dissassemble and reassemble once the cleaning is done?
Sounds pretty easy...