Mercury 25 HP Outboard/Jet Converison

[treeguyus]

Any particular comments on this outboard. Looking at purchasing a 1648 Alumacraft Jon Boat with a 25 1985 hp Outboard jet conversion. Know it would be good in shallow water. The seller had the motor converted, and raised the transom for proper function of motor. Looking for this to be a second boat for small inland lakes and occasional river fishing. The seller wants $3000.00 for package with trailer and find that the conversion cost is around $1700.00 alone. My thought is the 1648 jon boat would be very stable and easier to get in and out of access's when compared to a 16' v hull. Any thoughts or experience would be appreciated shared link to show how it is rigged claimed for best performance.

 

[flyingscott]

I would test drive it because I don't think it would get on plane. Remember jets are about a 30-40 % power loss which means your 25 is now a 15 or less with the jet attachment. Looks like he put a long shaft on a boat that could use a shortshaft. Depends on what you are looking for and how much you load it up. That motor looks newer than 1985.

 

[Stumpalump]

I would test drive it because I don't think it would get on plane. Remember jets are about a 30-40 % power loss which means your 25 is now a 15 or less with the jet attachment. Looks like he put a long shaft on a boat that could use a shortshaft. Depends on what you are looking for and how much you load it up. That motor looks newer than 1985.

You have to jack the motor up like that when you convert or run a jet. I think it's 5 or 6 inches.

 

[flyingscott]

Thank you i did not know that. Still test drive it

 

[treeguyus]

I agree to test drive it!!! What is a mercury jet 25 HP worth? It is a 1985.

 

[Texasmark]

On the 3 cyl and 4 cyl loopers service manual the conversion is 75/60 to take one. That's an 80% of 25 for 20 hp. Again, I say that's plenty of power for that boat.....BTDT. What I see as a problem is the fact that when he jacked it up the 5-6" allowing for Jet to run at the proper depth, the tiller handle will be at the back of your head, not down around your belt line. You'd have to stand up to run that boat. In that case a tiller extension would be in order.n

On 3k price, what it's worth is up to you. Nothing there is new and whether you know it or not, and you probably do, regardless of what you do to something on a whatever, it doesn't register with the buyer.....salesman taking a trade as an example. He goes by year model from the "Blue Book" or such and very little room in there for moving around.

That's the way I see it,
Mark

 

[flyingscott]

Check the serial# on the motor looks like gray and red stripes 1985 would have brown. There was a post in the evinrude column a factory 75 hp 3 cyl jet rated at 40. The mercury 80 hp jet is built on the 115 powerhead you will also be down on power and jets get horrible fuel mileage they are not efficient at all

 

[ondarvr]

It will work, but performance will be marginal, and with much of a load you won't be going anywhere. The reason it will work at all is because the hull is so light.

A 60/40 would be the biggest you would go on that narrow hull. My 15.5 has a 90/60, my buddies 16' has 100/70, ours are a little and wider heavier though.

The 30% reduction in power is a rather optimistic estimate for advertising purposes, it's more like 40%, maybe more.