Should I Swap the rockwell JLO with a military 4A032 engine ?

[Sticky]

Hello everyone, I'm new to this 6x6 owners world and in need of help. I have recently purchased what I believe is a mid 1970's max II. The whole thing is rough. It has a Rockwell JLO that has no spark. I've read here about what to do to get spark. It also has the ballon style tires ,5 are flat . the tub is good .the top is rough. The drive train is crusty but solid. so I have a nice project.

Now I've pulled the motor. I'm wondering which direction I should go.

Are the rockwells good enough engines and strong enough for me or should I put one of the military 4A032 engines in there. They are 20 hp or more ,.approx 50lb ,opposed 4 cyl 4 stroke with approx 500cc displacement. Here a link to one on u-tube.



http://http://www.youtube.com/watch?v=rKIhvwIS4A8YouTube - First startup for 4A032


I already own one of these military engines so the modification would be the investment.


My major concern is clutch selection. Should I find a larger clutch asembly for the 4 stroke(maybe 4000 rpm max) or use the original clutch assembly (Rockwell turns almost 6000rpm from what I've read here).

I don't know much about these clutch assemblies thats for sure.

I'm thinking the 4 stroke would be a much quieter engine also. What kind of fuel consumption do you see with the rockwell?

Please submit your opinions on this matter .


sticky

[6X6]

Hi Sticky. The JLO Rockwell has a tapered crankshaft, you're 4A032 most likely does not. You'll need a new clutch. Anyways, if the clutch you have is the correct one for the JLO and you do fit it on the 4a032 it won't open up fully with the 4-stroke, and you'll loose more speed that just on the drop in RPM. 50lbs seems kinda light for a 4-cylinder 4-stroke, is it an aluminum block?

Now, what JLO motor is it? There will be a tag on the block with the displacement engraved in it, (if it's still visible, wipe off any dirt and you should find it pretty easy), but for starters is it a single or twin cylinder? A L295 Single is rated for 21 hp and 6500 RPM, the twins will vary but will be a bit more, 28-36hp guessing each head is 4-bolt not 6 bolt (IF each head is 6-bolt it's rubbish and should be shipped to me immediately OK, sorry, the six bolt heads are 5-port motors and make more power, 32-48 depending on a 340, 400 or 440, but they are pretty rare) You can tell by looking around each plug, either 4 studs in a square or 6 in a hexagon. Personally I'd go with the 2-stroke but maybe I'm a little biased Knowing the JLO motor you have will make it easier for us to compare the 2 vs. the 4.

[thebuggyman1]

What kind of driving did you have in mind?
It's hard to beat a 2 stroke for racing, but a 4 stroke makes a much more user friendly trail machine. The best solution is to buy a second machine so you can have one of each!

If you post where you live, you may find someone close to you with spare parts, (I have a bunch, and a 4 stroke machine too).

[Sticky]

I have the 340 cc 4 bolt. I would use it as a general purpose, hunting ,fishing machine.

[6X6]

Well a 2-stroke isn't the best for those, the 4 won't be silent but it'll spook less animals land or water than a 2. That's rated for 28 hp so it's no slouch, but since you most likely value ease of use and quiet over speed you may want to look into the 4a032. I'm not sure who's in the Binghamton area. You're roughly 3 hours from me. From what I have found, that motor is roughly 110 lbs. Is this one lightened somehow? Or did someone misquote weight.