2003 XB w/ Yamaha 150

[fastguy]

Has any one tried the above boat with the 150 hp Yamaha 4 stroke?
I am thinking about repowering and am curious.
I've rebuilt the Pro Max several times, enough is enough.

Thanks

George :?: :?: :?:

 

[Lotus 50]

A 4 stroke is not the obvious answer
Yamaha claims 466 lb dry for the 150, ie less gas and oil
150 HPDI lists at about the same weight but it would be lighter in real life and have more torque

 

[fastguy]

Lotus, thanks for the reply, I use my boat daily to fish, the high performance end of it is getting old fast. This is the second go around on pistons, these were top pinned used forged items.
My daily fishing trips end up being about 25 to 30 miles, the fuel economy is getting more important than ever thus the interest in the 4 stroke.

 

[froggy]

FastGuy,

I think you have a great idea. Hole shot may suffer a bit, but that can be worked. Why don't you do it and let the rest of us know how it comes out. I know that there will be some performance enhancements coming down the pike for the Honda 4 cylinder, 4 stroke and assume that Yamaha won't be left out.

Just remember, it takes approx. 15 gallons per hour to make 150 HP whether you are 4 stroking or 2 stroking.

froggy

 

[dspencer]

A 150 optimax will get you just under 6mpg at 60 mph. Its lighter than the 4 strokes and should last many many years. A 200xs will do even better on gas but not sure of the longevity. I am told it will last.

A 4 stroke is good if you want quiet. I don't think its better on gas than a dfi.

 

[fastguy]

Spencer, I have seen you at Cedar Creek. I have a red Allison.
I have been talking to the Yamaha dealer here and he seems to want to sell an engine. The Mercury dealers in this area seem to think they are gold.

Thanks,

George

 

[dspencer]

George, hello brother. Yes its me. My daughter seems to spot you every time we're out on the lake. Our next and final Bass Champs is on your lake and we have been out there a few times.

If you need to get rid of your motor you might have luck on screamandfly.com

I hope you aren't off the water too long. Too many fish in that lake.

I know you aren't too much into racing but catching so miles per gallon is where you're looking. The 4 stroke will do it as well as the direct fuel injection motors like the opti's. My motor will match a 4 stroke on fuel and should live a long time. Its also lighter, slightly. Hey, call me I could tell you where I got my motor. Way under 10 grand. Your motor harness and throttle/shift linkage would also be the same.



214 629 7124

 

[hack02]

I remember reading a test in B&WB featuring a boat , generic like a Nitro or something, with a 150 Yamaha. The 150 was a dog. It wouldn't get out of its on way. Struggled to plane and a very dissapointing top speed. Seems it would only go about 50. I remember them saying it was because it was based on the 4 cyclinder block, no displacement.
If you have to go four I would look at one of the V6 engines. Close to the same weight but alot more performance. The dealer may be trying to steer you to the 150 just because he wants to get rid of it.
Just go ahead and buy a leftover 280 and hang it off the back. :lol:

 

[fastguy]

Hack, that may be a good idea just to see what will break next. I like the idea of the four stroke. I think that with a little set-up work it can be made to perform, not like a 280 but still get out of its own way.
BWB has published more than one erroneous test.


George

 

[jaybluez]

That's right Hack. It was tested on a blazer 180. Top speed was 58...compared to the 2 stroke I had on the same boat gps was 69. Big difference! Also holeshot was 11.3 seconds. With my setup I could just about completely launch the hull out of the water on holeshot. And up to 30 was no prob. Just couldn't keep the hull from splitting on the blazer. When I saw that allison for sale I gave that blazer away and I have 0 regrets. Best move I've ever made. Although, if it's not performance that is being sought then to each his own.

 

[John Richied]

Switching to a four-stroke, it would be a lot quieter and probably live a lot longer then a two-stroke.
As for fuel mileage I would get a 200 hp or bigger, then you wouldn’t have to run it wide open as often and you would be able to turn a bigger pitched prop.
Another nice thing about the four-stroke is you would be saving a lot of money on oil. So even if a 200 hp four-stroke and a two-stroke got the same fuel mileage you would be way ahead with the four-stroke.

Now the downside would be if you bought a Yamaha, Honda, etc… you would have to do something about the gearcase, like add a Bob’s nosecone.

The best option with what you have right now in my opinion would be to buy some brand new cast pistons for your Merc ProMax. Buying used forged pistons means those pistons have been in a 2.5 Merc screaming over 7500 Rpm’s and at sometime that engine blew up.

 

[fastguy]

John, thanks for your response, I think the larger four strokes are a little heavy for an Allison. I agree with you on the low water pick-up mod.
I guess the thing that peeves me the most is the expence of the replacement parts, I'm all for some one making a profit but the prices they want for the Mercury parts are obscene and new motor prices are worse.
I also agree on the used pistons that have been top pinned, I had a ring break, the piston and the pin was still intact except for the ring land. Of course it scored the block. The score is now 2 blocks, 2 front halves and 2 sets of pistons all on a motor that was seldom over 5,000 rpm.

George

 

[GrandLakeGAR]

In 1996 B&WE tested a XB2003 with a 90 HP Honda four cyl, four stroke. Ran 58 light with a Hoss Triton and 49 loaded with a Trophy. 6.8 miles per gallon at 5900 rpm but not much other test detail. GAR

 

[fastguy]

GAR, Thanks, I spoke with a sales rep from Tennessee that thought a 150 would get to the low to mid 60's.
Maybe we could get Tiger to test it, then it would run in the 80's.
I know the lower unit will have to be modified for a LWP but that shouldn't be that big of a deal.


George

 

[froggy]

Fastguy,

I didn't need a LWP/nosecone on my XTB-21 until I exceeded 78 mph. The rig would blow out at 78 mph, until I added the appropriate lower unit. The point I'm making is that you will not need lower unit work if the boat will only run in the mid 60's. Just keep the lower deep enough to get water pressure.

froggy

 

[dspencer]

I am running the 150 opti and it will get 72 with no low water pickup in the winter with a very light load.

Right now with a 26 worked trophy plus I am going 65 to 66 with my regular tournament load. I am sure a little tweeking could possibly get me a little more but its doing fine, really. I get good mileage too.

I am sure the 4 stroke can be made to do almost the same as my boat with the downsides only being the extra 30 or so pounds. The Yamaha would cost you a little more but its worth a try.

Now wouldn't it be a crying shame to mislead everyone out at Cedar Creek with the only two Allisons running under 70? Froggy come save us.

 

[fastguy]

Froggy and Spenser, thanks for the replys, I thought that by getting the prop up it would free up and pick up a few mph. Not too worried about blow-out at this time. 6mpg would be good though.

George

 

[fastguy]

It's getting closer, those suckers are hard to find and pricey when you do.
I've taken most of the Merc stuff off of the boat, I wonder if any one ever weighed a 225 Pro Max. The pieces seemed heavy to me, my wife had a hard time carrying the center section to the garage. :roll:


George

 

[John Richied]

my wife had a hard time carrying the center section to the garage

How much does she think the powerhead weighs...?

 

[fastguy]

She only got upset when she stuck her hand in the exhaust cavity to carry the short block to the bench. Her hands were already dirty from changing the oil in the lawn mower, I don't know what her problem is.....


George