swapping engines-JDX4 to 300

grantnelson00 · Post by **grantnelson00** » Mon May 15, 2006 1:25 am

I recently purchased a JDX-4 and a JDX-8. The 4 has a 295 which should slip into the 300. I plan to use the 4 for parts and the JDX-8 for driving.

My question is:are the clutches from the JDX-4 and the 300 the same or are they different? Do I need to take the clutch from the old engine and put it on this one?

Thank-you

grantnelson00 · Post by **grantnelson00** » Mon May 15, 2006 1:30 am

I better clarify that. I have a JD 300 that needs an engine and that's why I purchased the JDX-4. The JDX-8 will get a few donor parts from the JDX-4 also.

grantnelson00 · Post by **grantnelson00** » Mon May 15, 2006 2:45 am

Thanks, Rich. I'll check the serial numbers in the morning. I'm glad you know what you know. It sure makes things easier for guys like me.

JDXsand00s · Post by **JDXsand00s** » Mon May 15, 2006 8:54 am

Wouldn't the X4 have a Salisbury on it? Your 300 should have a Comet and if this is the case then you should put the 300's Comet 100c on your X4 engine.

JDXsand00s · Post by **JDXsand00s** » Mon May 15, 2006 3:50 pm

sorry about the mistake, recent check of the service manual shows that they all did have 780s. My question is, Rich, did Deere have a replacement program then for the 850's? I though that all Salisburys were phased out after the 73 model year but i guess not. I am also so used to having all of my green machines replaced with Comets and a pile of junk 780s and a 910 i think i my basement. Thanks for pointing out my mistake and good luck with the 300 Grant, can't wait to get some snow and take all of my newly fixed sleds for a spin.

JDFanPa · Post by **JDFanPa** » Mon May 15, 2006 9:09 pm

Grant once you get things bolted down and running you could play around with a few things if you want. I have a 1974 300 and a 74 jdx4 both same engine. On my 300 I have a tillitson carb and unknown brand clutch from an arctic cat 340 kawasaki motor. Not sure why but the the 300 is a much quicker sled. Keep in mind I only put these parts on the 300 since it needed them and those are what I had laying around. Bur for some reason the 300 ended up being much faster. Not that you need to do this stuff just something to keep in mind if you want to tinker with things.

grantnelson00 · Post by **grantnelson00** » Tue May 16, 2006 2:25 pm

Any, Rich, Ryan;

Thanks for all the help. The serial number is below the number Rich gave me so it should be all green lights. Jeff from Cannon Falls, Minnesota is bringing both sleds up on Saturday during the VSCA show at the Engelstad Auditorium in town.(Thief River Falls, Mn)

I fear I may give into the temptation of swapping engines that very night after the show. Thanks again.

400brian · Post by **400brian** » Tue May 16, 2006 5:22 pm

Hey Grant

I thought you were getting the original engine overhauled?
What did you run into on that?

grantnelson00 · Post by **grantnelson00** » Tue May 16, 2006 7:05 pm

I took it to Northern Crankshaft in town. This is a machine place that both the Arctic Cat and Polaris dealer recommended. Northern said that there was so much wrong with the engine that it would be cheaper to replace it that repair it. This turned out to be true as I purchased the JDX-4 and JDX-8 for only $50 and the JDX-4's engine is supposed to be excellent and the JDX-8 is running but needs a little work. It would have been nice to keep it original but I already had a fair amount of money into the 300 so I decided this was the better route.

grantnelson00 · Post by **grantnelson00** » Tue May 16, 2006 7:08 pm

Also I don't remember everything wrong but part of it was seals and a cracked piston. His shop rate was $45/hr so as I remember the labor was what was going to be the real killer

JDFanPa · Post by **JDFanPa** » Tue May 16, 2006 10:05 pm

Id say your taking the right approach on this Grant. There really isnt anything non original about using the x4 motor it is the same thing after all. Fixing restoring this sweet sleds can get costly enough doing it yourself let alone when you have to start paying hourly labor rates. DKTrader has the complete gasket sets and rings for cheap most of the time and you can keep your eyes out for pistons as Ive seen them on there too. If you feel inclined gather up the new parts as you find good deals and maybe 1 day you might want to tackle the rebuild job yourself. Or at the very least you will have the parts for the job when you take it someplace. For now just drop the motor in and ride the heck out of her. Ive got my 300&x4 in running order and a spare rebuilt kohler on the shelf just incase in all honesty Ive got a spare or 2 motors for most all my deeres on the shelf.

grantnelson00 · Post by **grantnelson00** » Wed May 17, 2006 8:40 pm

Thanks, Rich!