In this post I would like to address issues that some have had starting their Yamaha 1049 cc 4-stroke engines. This is not only a Viper/7000 issue but I have also witnessed it on a Vector. It happened in Cochrane with morning temperatures below -30C. From what I could see the engine would crank somewhat slowly and try to fire but just not start and stay running. The battery was not down, the oil in the main and rod bearings was just too thick to get a good fast cranking speed to get good cylinder pressure to start. The battery in my 7000 is even smaller, I believe, than in the Vector. That along with the fragile starter idler gear issue, made me decide to add some heaters to eliminate this issue when the temps are real cold. Playing around with hair dryers and booster boxes is not a good way to start the day, especially when your small 2-stroke buddies have their engines running and are ready to go.
A proven solution to this problem that has been done on the Vector, is to heat the lower portion of the engine. There has been no starting issues since, no matter how cold is gets. This solution does not heat the engine coolant therefore does not trick the ECM into a no cold start routine. The heaters used are only 50 watts each and are plugged in at the end of the day to keep the lower engine cases warm enough to keep the oil around the main bearings from getting thick. They do not get too hot all night due to their low power. The heaters we used were Kat's Silicone Pad Self Adhesive CSA approved 2" x 5" 3-prong part number 26050. They are available on Amazon.ca for about $32.95 each.
I mounted the first heater on the smooth surface of the bottom of the oil pan. There is an area that is just the right size for this 2x5 inch heater. Clean the surface with some solvent so it has no dirt or oil and let it flash off. Stick the heater on and firmly press it down so there is no air voids between the pad and the pan. Add a bead of high temp silicone around the edge to seal out any oil or water from getting under the pad that could loosen it.
I mounted the second heater to the front side of the engine block in the flat area above the pan rail. I had to smooth the area of casting flash with a die grinder and Scotch-Brite disk.
Run the cables away from any hot pipes over to the right foot well. I covered the cords with split plastic wire loom and then wrapped the loom with aluminum duct tape to reflect heat.
When the heaters are not needed down in the south, the cord ends are tucked up under the plastic tank cover. All you need to carry is a triple tap 5 meter extension cord. Make sure you buy a lighted end so you know there is power in the outlet. I use the third tap with a short cord over to my other sled parked beside. You will be able to unplug the cord and wrap it up during packing and jump on the sled, turn the key and go. You can watch others fight with hair dryers removing covers and trying to borrow booster boxes while you let the engine warm up.
Happy sledding !
BP
