Jett in a boat?
 

Hi guys,

I know this is a question for the BOAT forum but since i got no answer there...

Just a thought if one took a Jett engine, coiled some copper tubing around the head (water cooling) & with a flywheel it should perform well on a HYDRO type boat, right?

If anyone tried it let me know what size engine/ flywheel/prop combo

Thanks, Vasek

RE: Jett in a boat?
 

Since Jetts use a seperate head insert and head clamp setup, it should be fairly easy to make a water cooled head. It would certainly work a whole lot better than just wrapping some copper tube around it.

RE: Jett in a boat?
 

It has been done before.
Some enterprising folks built there own liquid-cool heads.
As noted, the finned section is just a "clamp" to hold the head button on.
But you will have to make your own cooling head or jacket.

One I know of was even mated to the K&B outboard bottom end.

Installing a flywheel drive is easy... but again, you have to make one that fits the Jett collet.

Issue most run into.... is the sport engines are not designed (timed/configured) for the rpm the boats need.

Engines offered from CMB, Picco, OPS, OS, K&B, TT are set up for marine use. All make good engines. And in the long run, are probably less expensive.

Bottom line.... its possible, but consider it an R&D project ---- will not be plug-n-play.

RE: Jett in a boat?
 

thanks but NO thanks , too much work[>:]

I ordered me one of those OS .46VX-M :) for my comeback in boats (haven't touched one since i was 14)
http://www2.towerhobbies.com/cgi-bin...?&I=LXBY94&P=7

just so you know it will power a "retro" styled SK Daddle .40 (see pics for inspiration)

Bob I know you're an engine buff, so let me ask you a question about the tuned pipe recommendation for the OS .46VX-M on the TH website :

" IMPORTANT: A .65-.90 size tuned pipe MUST be used with this engine.
Using a smaller tuned pipe will cause engine failure"

an "oversized" tuned pipe for the .46 ? WHY??? I did ask this question over the boat forum, got an answer that one guy uses the 40 size tuned pipe on this engine (he wasn't aware of this recommendation) and he says he's got no prob.(?)

Hope to see you all "speedsters" at the boat section too;)

RE: Jett in a boat?
 

The engine needs the massflow and volume of the bigger pipe.
Not sure why you would want to go over an 8.5cc marine pipe though.. but they must have a reason suggesting a 10cc pipe.

Also might have something to do with heat, heat build up, exhaust temperature... and physically melting something?

RE: Jett in a boat?
 

Mac’s 8.5 cc aircraft tuned pipe should will work fine as they do on my 45 vx-df 's. Mac's doesn’t offer an 8.5 marine so you must go up to the 11 cc. When it get’s on the pipe…look out! It’s all the sudden on the marine pipe.

RE: Jett in a boat?
 

freaking, what is the difference between the standard & the marine pipe? can the std. pipe be used for marine applications?