# Advice on a jet conversion....Again.



## reedjj (Jan 21, 2013)

Hey guys,

I have a 2002 G3 1756 with a 2002 2stroke 40Hp yamaha. https://www.tinboats.net/forum/viewtopic.php?f=3&t=20508&hilit=g3+1756+CC+DLX And once again I am thinking putting a jackplate and jet foot on the motor. I know my 40hp will only be a 30hp with a jet unit but I have done some reasearch and think it will run just fine.....

I found that my hull is only 5" longer than the current model 1656CCJ (the 1656CCJ is 16' 5" & my 1756 is 16"10) and somehow my hull is about 40lbs lighter (dryweight). According to yamaha performance bulletin website https://www.yamahaoutboards.com/owner-resources/performance-bulletins the 1656CCJ runs 27.4mph WOT with the fourstroke 40/30 jet, and it only runs .3mph faster, 27.7mph with the 60/40jet? Which is the max you can get on it from the factory. I'm sure the extra HP will matter more when hauling a load. These numbers are for the current models of the boats and with 4stroke motors. My boat is a 2002 G3 1756 CC that does not have the storage in the front deck, the huge fuel tank up front, or the live well. Plus my motor is the 2 stroke and is 60lbs lignter than the 4 stroke 40/30

My thinking is that with my rig being about 100lbs lighter than the 1656CCJ I should see at least the same performance? I have also heard that the Jet tunnels are a little slower because the tunnel creats drag. Since my boat is not a tunnel, and its 100lbs lighter I am feeling pretty confident that it will run around 27-28 mph with my 40hp 2smoker spinning a jet.

I have heard some say that the performance bulletins are BS but what else are we supposed to use as a guide?

Before anyone says it, I will state in advance that if I had the money I would have already bought a 2 stroke 90hp yamaha with a jet on it and been done. Or bought my dream boat. A 2072 SeaArk pro jet tunnel with a 150/105 jet, fwd console, and pods! But modding my existing set up until my finances improve is my solution to getting back in the shallows where the big redfish are for the next year or so. LOL!

I would really like to hear from someone that has, or has been in a G3 1656CCJ with the 40/30 jet.

Any and all advice is appreciated.
Thanks
reed


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## fishbum (Jan 21, 2013)

reedjj said:


> Hey guys,
> 
> I have a 2002 G3 1756 with a 2002 2stroke 40Hp yamaha. https://www.tinboats.net/forum/viewtopic.php?f=3&t=20508&hilit=g3+1756+CC+DLX And once again I am thinking putting a jackplate and jet foot on the motor. I know my 40hp will only be a 30hp with a jet unit but I have done some reasearch and think it will run just fine.....
> 
> ...


Hi There, Have seen a lot of guys underpower boats and hate them after! the 40 will be on the downside for sure.
now I have herd if you add 50hp carbs and something else you can ge more hp, same block and cube inch.
you could sell your motor and find something larger? I am a dealer for outboard Jets, and live in the Atlanta area.
I can save you some money on a new pump if you go that way. Outboard Jets gets real bad about stock! can be awhile.. yes a 90 or even a 115 would be great. 1 just picked up a clean 90 Suzuki 2 stroke 1996 I think. not a jet but can get one for it. If you want call me and we can talk about pumps and such. Also I am looking at a boat in Ormond beach you could ck out for me! Barry


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## Lil' Blue Rude (Jan 21, 2013)

Yeah the 40hp will be a little on the small side but I know people that have them on 17' 52" that carry 4 "healthy" adults and everything besides the kitchen sink. Put 50hp carbs, 50hp or hydro tech tuner(exhaust) and some Chris Carson reeds and that will help perfomance. If you want a little more you can shave the head. Carbs and exhaust should be good for a couple hundred rpm if not more. Lighten the fly wheel to get some more pep out of the hole and it's easier on the top bearing.


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## Seth (Jan 22, 2013)

I had a 1648 with a 50/35 Yamaha 2 stroke on it and it was great with two regular sized people. Much more more then that and it ran like poop and I didn't like it. My buddy had a 1752 with a Mercury 60/40 2 stroke and it ran much better with a load. I now have an 1852 with a 115/80 and it runs like a jet boat should! We can load her down good and she will still jump up on plane and scoot along mid 30's. I know you need to keep your finances in check but underpowering your rig, especially with a jet, will just make you mad at it.


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## reedjj (Jan 25, 2013)

I keep trying to find a way... LOL. Doing all that to my little 40 would cost more than just selling it and getting a 60 or 90 2 stroke. Same way with just slapping a jet unit and a jackplate on. Jackplates are around $300 and a Jet unit is around $700. 

Fishbum..

How much would a 90 with a jet run me?


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## andrewt (Jan 28, 2013)

Buy a motor with a jet on it or put a jet on your motor. You know you want one and you know it will work for you you just need the reasurance that it will work. It will, so buy a jet motor and rebuild it, buy a good jet motor or convert your motor and send us some pictures. That will solve your curiosity of a jet motor and us reading the same posts year after year. Not meaning this malicously just saying answer your own intrige and curiosity. Bigger is not always better. a 200 will run a little better if you have the boat to push but a 40 can outrun a 250 depending on weight and mods. If u have a 17 ft boat a motor 90hp and under will run just as good as a 150 as long as you don't put 300lbs of tackle in it. if you wanna haul weight go v4 or so if you wanna boatride in a litte jet boat then get a 40-90hp and lighten it up as much as you can. Use your motor with a little less weight and you'll be happy. Get rid of the slow mercury and go with a light weight boat and an evinrude or johsnon and talk to little blue rude and do his mods and you'll be beyond happy. Just comit to what you really want and quit kickin this idea around and send us some pictures please.
drew


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## RedfireSVT (Feb 7, 2013)

i have a 2005 1756 G3 that looks like the same boat as yours but it has a 90hp 4 stroke and i am converting it to jet drive as well. i have the lift plate and jet foot from outboardjets.com, i just have to get some help to get it installed. with a 40hp i think you are going to be very under powered with a jet.


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## fowlplay (Mar 20, 2013)

You will be disappointed with the performance of your boat. I have been running a 14/48 misc for the past 5 years with a 50/35 and with me only boat jumped on plane fast and would do 28 wot god but add weight two additional people and a 100lbs lab and it became a dog. I just rienforced transom and upgraded to a 70/50 two stroke 227 lbs and I'm back in bussiness even with a full load. I'm happy again. Me only in boat 36 gps. If I had a 17 foot boat and unlimited budget is b looking at more than a 90. When your ready to upgrade pay attention to motor weight. A 90 and a 115 weight the same. No brainer buy the 115. Good luck fishing. Enjoy what ya got.


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## RiverBottomOutdoors (Mar 22, 2013)

I just bought a new G3 1656 CCJ with 60/40J. The performance info for WOT is pretty much spot on. 

I'd guess that it's heavier than your 1756 because it has a larger front deck with two dry storage lockers, a larger aft deck, 19 gallon livewell and a 12 GA gas tank.

I like your 1756. Good looking boat. Nice work.


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## reedjj (Mar 23, 2013)

I Love ur boat riverbottom.


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## Lennyg3 (Mar 29, 2013)

You can probably sell the 40hp, and find a 60/40 jet for close to the same money to be honest. IMO that's the route I would go. I think, as others have mentioned, you'll notice the difference when you load the boat up.


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