f150swartz
New member
i just bought this sled last week, im trying to figure out what it is, im not sure it the engine is the proper one for it or just what any help would be appreciated... the engine has the numbers S433 - 039374 on the shroud above the recoil, has 433cc sc on the bottom of the block... ive tried looking online to find out what its from so i can get parts there are no tags on the sled at all... i only want the engine anyways but i need to know what its out of...
all the ones ive seen online dont have the same carb as this... they have the fuel pump right on the bottom.. this one is separate..
oil injection but it isnt hooked up.. the fuel in the tank is premixed...
.... Please note this is how i got it, i havent done anything to it
all the ones ive seen online dont have the same carb as this... they have the fuel pump right on the bottom.. this one is separate..
oil injection but it isnt hooked up.. the fuel in the tank is premixed...
.... Please note this is how i got it, i havent done anything to it
Whats the ser. number stamped in the tunnel on the right hand side. It will be towards the front.
f150swartz
New member
the tunnel is pretty well full of bondo and what looks like rubberized undercoating and plenty of newer thicker steel..... i looked inside and out of both sides i cant find anything thanks though... if i get ambitious after the long weekend maybe ill see if i can get under the bondosledder1 said:
f150swartz
New member
how far from the front would it be? how far between the top and bottom? that way i dont have to clean the whole 3 feet. And on the outside righthand side?sledder1 said:
motorhead327
VIP Member
I wonder if its the SM292 with the SR433 engine. Year 1973 http://www.yamaha-motor.com/sport/epic_snow/epichome.aspx
i show the 1977 GP440 having a starting engine number of S433-038101.
the vin is typically located just below where the seat meets the fuel tank
the vin is typically located just below where the seat meets the fuel tank
f150swartz
New member
Are the sr 433 free air? thats how it looks to me in the picture on the yamaha sitemotorhead327 said:
f150swartz
New member
so you think it might be a 77 or newer gp440 engine? what about the carb? anything ive seen online in terms of part schematics its not the right carb on it... and tue oil injection isnt hooled up.. doeant even have an oil tank.....snowdad4 said:
someone changed the carb, its not original. seemed to be a popular mod over the years to ise the round slides. 77 was the closest match to your engine numbers. no single S designation after 77. in 76 there was the Prestige 440, engine number S433-035101
f150swartz
New member
So its a 77 gp440 engine? I saw somewhere that at 433 and 440 have the same bottom end is that right? anything else you can tell me about it? i need to know as much as i can about the engine i plan on using it somewhere else.... how would i go about makong itvrun better in warm weather?snowdad4 said:
hopefully someone else will chime in. fitment and crossovers on those older sleds are out of my realm.
to make it run better in warmer temps, you would have to play with the jetting. warmer = richer. reduce the main jet size slightly and even play with the needle setting. any way you can duct air directly towards the engine would be to your benefit.
to make it run better in warmer temps, you would have to play with the jetting. warmer = richer. reduce the main jet size slightly and even play with the needle setting. any way you can duct air directly towards the engine would be to your benefit.
f150swartz
New member
Is there a way to wire a small electric fan up to the engine? since it doesnt have electric statt theres no battery also is it possible to put electric start on this engine it would be beneficial?
adding an electric fan would not be a problem, you would just need an external power source(battery), doubt the ignition output would run it.
easily done with an atv/mc battery, a toggle switch and the fan.
as for the e start, i dont know if that was an available option for your sled or not. seems viable.
easily done with an atv/mc battery, a toggle switch and the fan.
as for the e start, i dont know if that was an available option for your sled or not. seems viable.
f150swartz
New member
snowdad4 said:
how do i keep the battery charged though? i wouldnt want the fan to quit and not know it..
simply charge the battery during non-use periods and have it ready for the intended use period. no need for constant run in theory, use as needed.
air flow over the engine while in use would reduce the need for the fan. fan would come to play in slow moving/lack of airflow situations.
think outside the box.
air flow over the engine while in use would reduce the need for the fan. fan would come to play in slow moving/lack of airflow situations.
think outside the box.
f150swartz
New member
I plan on putting it in a golf cart im sure i can get air to it somehow... does anyone know what sparkplugs i should use in the engine and what to gap them at.. right now it has ngk b9es in it
Yamaha Nutz
New member
from what i can see the sled is a 76-77 gs 433 the motor and the seat and tank combo tell the whole story if it is a true GS should have a 8A7 track and slide suspension that looks like part gpx and part Exciter .............if it is boogie with center drive just a GP