Someone please help me!

[c nichols]

i was recently given a rockwell 2f440-7 snowmobile motor and i am going to build a go kart with it but i need some electrical info on this motor.
it has 5 or 6 wires coming out of the block but i don't know what they go to. i was told it will run as is but i would like to put a kill switch on it.
it is a two stroke with dual exaust...do i need expansion chambers in the exaust?

any info is better than what i have...

thanks

 

[Kaptain Krunch]

i was recently given a rockwell 2f440-7 snowmobile motor and i am going to build a go kart with it but i need some electrical info on this motor.
it has 5 or 6 wires coming out of the block but i don't know what they go to. i was told it will run as is but i would like to put a kill switch on it.
it is a two stroke with dual exaust...do i need expansion chambers in the exaust?

any info is better than what i have...

thanks

Are there coils on the motor? if not the 5 or 6 wires go to the coils. If there are coils then the wires are for the headlights, tach, etc. You do need expansion chamber exhausts, most twin cyl sleds use one pipe with a Y fitting to combine the two exhaust ports into one. 2 pipes is obviously better. I've never heard of a rockwell sled engine, but im sure you can find an exhaust for it on ebay or at a scrap yard.

 

[Affair_driven]

Expansion chambers aren't really a necessity. Their use, however, does boost power.

 

[Kaptain Krunch]

And efficiency.

Have you ever run a 440 sled engine without the expansion chamber (straight piped)? They never seem to run right for me, maybe you would have to change jetting because of the loss of fuel out the exhaust?

 

[Affair_driven]

If carbs are not adjustable, then a jet change may be necessary.
If expansion chambers are used they must match up to engine requirements. Requires a lot of math to get them right.
Can't just throw anything on there.

 

[anderkart]

it has 5 or 6 wires coming out of the block but i don't know what they go to. i was told it will run as is but i would like to put a kill switch on it.

If you cant find a wiring schematic, (the tachometer wire is normally the one you'd connect to a kill switch on many other types of engines) here's something I'd try to figure it out if it was mine.

When you get it running, get a regular automotive 12-volt test light (make sure it works/test it on a car battery first) and ground its alligator clip to the bare clean metal of the engine somewhere, then touch the test lights probe to each of the wires one at a time.

I'm thinking you'll find only one wire will make your test light blink very quickly, and/or the test light might even act as a kill switch and immediately shut the eingine down. If you find a wire that does either or both of these things, I'm thinking you've found your kill switch wire. (but then again I've never worked on sled motors and could be wrong here :wink2:

 

[Rotore]

post pics

 

[c nichols]

i really appreciate the help. yes the coils are mounted on the motor. a rockwell and a jlo motor are the same.any more advice is very welcome.
thanks again

 

[c nichols]

thanks for writing... no i don't know anything about this motor.
i have a little basic engine knowledge but thats about it.

thanks again

 

[c nichols]

sorry, for some reason i can't post pics

i will keep trying to post some pics but i haven't had any luck so far.

thanks everybody for all the help