Yamaha outboard- swapping prop to jet leg

Charter Tofino

Well-Known Member
I want to put together a little jet setup. Pricing out a 40 yam was surprisingly expensive 7+k. I have a 30hp Yamaha 2 stroke tiller with only 200 hours on it so I was thinking I may as well try to convert that to a pump leg but can't find anything online or through phoning shops. Anyone on here have experience?
 
I have a 225 evinrude that I VERY occasionally swap out the prop gearcase with a jet gearcase - even with a SS impellor and tight fit on the wear ring - my experience is: lotsa noise, big loss in speed and steering response, very fussy about mounting height.

I only do it to fish in skinny water when we have low snow pack years - also, the boat has a hyd transom jack so I can adj height on the fly.

I think you will be disappointed by how little thrust a 30hp OB produces
 
I have a 225 evinrude that I VERY occasionally swap out the prop gearcase with a jet gearcase - even with a SS impellor and tight fit on the wear ring - my experience is: lotsa noise, big loss in speed and steering response, very fussy about mounting height.

I only do it to fish in skinny water when we have low snow pack years - also, the boat has a hyd transom jack so I can adj height on the fly.

I think you will be disappointed by how little thrust a 30hp OB produces
 
I have a 225 evinrude that I VERY occasionally swap out the prop gearcase with a jet gearcase - even with a SS impellor and tight fit on the wear ring - my experience is: lotsa noise, big loss in speed and steering response, very fussy about mounting height.

I only do it to fish in skinny water when we have low snow pack years - also, the boat has a hyd transom jack so I can adj height on the fly.

I think you will be disappointed by how little thrust a 30hp OB produces


It's going to likely go on a 14 ft zodiac so it won't need that much juice.

This is my current setup but I don't think it can run the skinny stuff.

 
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A 30 hp 2 stroke yamy will push a 14 foot zodiac real good. Its about 20 hp at the pump, lots to move you around. U should be able to find a pump to fit that online somewhere. There not cheap but might be a used one sitting around somewhere. A 60/40 on that aluminum would be real nice, saw a used one on craigslist vancouver a month or so ago.
 
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Outboard jet is the only company that makes outboard pumps. Call them up and have a chat. I had a 25 merc 2 stroke I converted and it would run 2 guys in a Lowe 1448 though some really skinny water. I think a new pump setup is about 2k for that engine. It is an hour to do the swap. Easy stuff....
 
I used to hunt with a buddy, he ran a 14' Lund with a long shaft 25hp merc jet pump with a 5" jack plate on it. Went amazing shallow with 2guys and day gear. If it was a long lake run he would run the lake with a prop motor and switch to the jet at the first pool. That saved us alot of time and gas.
 
I did the prop to Jet conversion on an old 18' Hewescraft river runner. The boat has an Evinrude 110 on it and I bought the R40 jet leg from a company in Boise Idaho. I also had to raise the transom 6 " and beef it up to hold the motor up higher so a couple of 1/4 " plates of aluminum sandwiching a marine grade 2"x6" and held to the stern with s.s. carriage bolts was the ticket. The stern is bulletproof now and stronger than it was new.


Boating and fish pics 1112.jpg

It is critical to get the leading edge of the foot lowered to just below the bottom of the hull (within 1/2"). Mine is about 1/4" below the bottom of the hull. This view is a little deceiving as it seems that the leg is much lower than that. It sits back about 3: from the transom, but with a ruler along the bottom of the hull, there is about 1/4" of the jet leg foot above the bottom of the hull.


1116.jpg


1103.jpg
 
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Wicked! Do any of you pump guys have experience with pull start engines? I heard pumps are harder to start and you want/need electric.
 
Wicked! Do any of you pump guys have experience with pull start engines? I heard pumps are harder to start and you want/need electric.


Buddies 25hp was pull start. Engine compression doesn't change. As said before, the shoe has to stick below transom by quarter inch, you want the best transition from boat to shoe as possible without creating air or turbulence. It should be as smooth as possible.
 
Zero issue with pull start on a pump. If your using it on a zodiac and planning on doing island rivers you want your butt end as light as possible, remember your backing down the big stuff and want to avoid digging in. Lighter the better!
 
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