Repower Time, 21 XTB

[ARLIN]

My 1998 150 Super Mag(with 2.5L EFI, 2.0 H/D Torque Master gearcase) sadly is down. Looks like it is time for new power given the price for new 150 EFI powerhead, oor fix and repair, etc. The compression is up,but Glenn and Jeff C. suspect plastic bearing cages have failed with bad crank.

The 150 Super Mag/Pro Max has easily pushed my 21 XTB 71-72 to maybe a bit more with driver only and good conditions. I've seen 74-75 upstream a few times with driver and light load on old Medallion water type speedo. About 69-70 WOT with two guys and some gear. The 2.0 gear gave super midrange pop for only 150hp on the 21 XTB.

Here are some of the options. Stock 150 or stock 175 Optimax, 175 Pro XS Optimax, and even a new 150 EFI with 1.87 gear and 60 amp charging like Optimax if I can find one at a good price.

Mainly would like to know of any recent top end history for a 175 Pro XS on a 21 XTB? And thinking the stock 150 Optimax and/or new stock 150 EFI, both with 1.87 gears would have a hard time breaking 70 mph?

Need feedback ASAP. Ha!

 

[Chad Phillips]

If I had a choice between the engines you've mentioned I would go with the 175 Pro XS. I don't know of any speeds attained with the Pro XS but Darris and Nancy had one on their XB21 at the rally.

 

[ALLISONMAN]

Arlin put ya that 175pro xs and you will be good!!!!!! Just amke sure glenn gets ya a deal on that thing!!!!

 

[ARLIN]

Arlin put ya that 175pro xs and you will be good!!!!!! Just amke sure glenn gets ya a deal on that thing!!!!

I get it--order a new Fury prop and keep pouring it on and skip signing up for Medicare. Ha!

 

[Dark Allison]

I like everything except the fury. I think the 175 Pro Xs will be a great choice. Gas mileage would be great. The verdict is still out on the Fury props.:smile

 

[ARLIN]

I like everything except the fury. I think the 175 Pro Xs will be a great choice. Gas mileage would be great. The verdict is still out on the Fury props.:smile

Thanks on the Fury prop. I have an old Laser II 26 that came via Allison Boats that Tim Hackney in Soddy-Daisy did years ago that I could test against. I have a more standard Laser II for everyday running.

To contine the general discussion--when I consider the 175 Pro XS I'm disappointed that it comes with only the stock lower unit--no solid mounts or T/M or S/Master type ugrade given the extra price for the 175 Pro XS.

(I'm more pived at no more mechnical steering cables from Mercury that is in effect costing me $1,200+ for hydraulic steering after already having paid for two sets (plus labor) of Mercury steering cables for the my XTB. Same for their bearings engineering and design problems that seem to only come out of my wallet. I'm wondering if Mercury Marine can be very far behind the GM and Chrysler scenario with the imports taking over the business?)

I've been going over several of the mph and ghp at various rpm for regular Optimax 150 and the 175 Pro XS. It has been hard to find tests on the same boat at the same time, temp, etc. Some of the figures are Mecury in house done, others who knows. The pattern seems to be much better mid-rainge fuel economy with all Optimax to about the same as regualr EFI at WOT. The WOT savings with Opitmax would be similar to a 1 mpg saving on an SUV from say to 2008 to 2009 that would take 30 years fuel savings at the 1 mpg to break even on the price differential.

..that's it for now..

 

[RedAllison]

One of your brothers customers has a 175 Opti (second generation, 2007. Wonder how much difference between it and the ProXS?) on a XB21 2+2. Stock 1.87 gearcase, we've played with several Hydromotives as well as a stock 26" Trophy and an A-cut 26" Trophy. The best I think we've gotten out of it (one man loaded) was 71 and change. The limiting factor is that gearcase. For warranty reasons he won't change gearcases. The boat reacts postively too raising the motor but then the motor starts loosing water pressure which puts the motor in Guardian Mode.

I think you'll see more than 1mpg gain on any of the XS motors. Mine gets AMAZING fuel mileage. The 3 days at the rally I burned a total of 25 gallons of fuel. That includes one 40 mile run on Cherokee and the 40 mile run from Louisville too Neyland Stadium and back. Before I slipped it in the water on Wed of the rally I had 70 hours on the motor and it had used 348 gallons of fuel. Not even 5 gals per hour average. I've bought oil 4 times in those 70 hours. They are ULTRA effecient!!!

Based on what similar motors and loads run on XB2003 vs XB21 2+2 I'd guess the XTB should be 2-4mph faster than the 2+2 with everything else being equal?

Hydro steering wise, SCREW those cables. Trust me after a day on the water with hydro you'll realize it's the BEST $1200 you'll spend.

Heck, have Glenn hang you a 225SportXS on dat ol boat. She'll EAT large then!!! :beer:
RA

 

[Darth VMAX]

Yeah, if you run WOT a lot of the time then there is not a very big difference at all between any technology 2-Stroke. If you think you will be running at high r's with the 175 to get satisfactory speed then you might look at getting something bigger that would run the same speed at a lower rpm to save more fuel.

RA, that really suprises me and at the same time disappoints me about the 175xs. I remember Wormie had a XB21 when they 1st came out in 03 (175 rating) and he had a 175 VMAX HPDI on it that ran right out of the box between 73-74 mph. Heck, I think Chris (Merc225/lightningrod) even drove it to that speed but I am not 100% on that.

 

[ARLIN]

One of your brothers customers has a 175 Opti (second generation, 2007. Wonder how much difference between it and the ProXS?) on a XB21 2+2. Stock 1.87 gearcase, we've played with several Hydromotives as well as a stock 26" Trophy and an A-cut 26" Trophy. The best I think we've gotten out of it (one man loaded) was 71 and change. The limiting factor is that gearcase. For warranty reasons he won't change gearcases. The boat reacts postively too raising the motor but then the motor starts loosing water pressure which puts the motor in Guardian Mode.

I think you'll see more than 1mpg gain on any of the XS motors. Mine gets AMAZING fuel mileage. The 3 days at the rally I burned a total of 25 gallons of fuel. That includes one 40 mile run on Cherokee and the 40 mile run from Louisville too Neyland Stadium and back. Before I slipped it in the water on Wed of the rally I had 70 hours on the motor and it had used 348 gallons of fuel. Not even 5 gals per hour average. I've bought oil 4 times in those 70 hours. They are ULTRA effecient!!!

Based on what similar motors and loads run on XB2003 vs XB21 2+2 I'd guess the XTB should be 2-4mph faster than the 2+2 with everything else being equal?

Hydro steering wise, SCREW those cables. Trust me after a day on the water with hydro you'll realize it's the BEST $1200 you'll spend.

Heck, have Glenn hang you a 225SportXS on dat ol boat. She'll EAT large then!!! :beer:
RA

First, I was typing this morning with a bad headache and no contacts on/or spell check on. Ha! (I've had Keratoconus the last 31 years--have had a cornea transplant and with a new hybrid soft/hard contact called Synergeyes have regained full 20/20 in my right eye after barely being able to see to drive a 70mph boat. Believe me that is a ride way beyond any Allison)

Back to the subject--lost the point a bit. Are you saying to expect the XB's 71 plus maybe 2-4mph with a 175 Pro XS on my 21 XTB? I had it down to 74-75 max for the 175 Pro XS on my XTB with one person, very light load, trimmed mostly out. Also I thinking 68 tops on my XTB with the stock CPO 150 Optimax engine that Glenn has.

Another point is I hate to get away from my current 150 Super Mag due to how easy it is to drive, H/D T/M gearcase, even the punch of the 2.0 out of the hole and mid-range. I got the XTB in 1992 at age 47 and after slow start got past chine walk once and for all. Have driven another XTB in 80 mph range. (Also in about 1994 Darris put that little Bondo wedge at the back of my XTB to take the slow down porpoise out of it--just a couple of spoonfuls made a tremendous difference in driving comfort.)

We haven't pulled the heads and the compression is still up on the 150 Super Mag, but it definitely bogged down and is pecking. I putt-putted her in after trolling from a mile or so a first. I thought I was the big dummy and let the oil tank lids get loose, but Saturday I could see that the small tank right near the flywheel was full of fresh looking Klotz. With my attention to water pressure, temp, and everything all the time and with my near stock type running, the 150 Super Mag should not have failure like it did? Guys are telling me plastic bearing cages of that vintage likely culprit.

Seems like the 222 Sport XS would be better overall value than 175 Pro XS. But, the 505 lbs a concern on XTB, but not the XB like yours.

..post on the speeds again..good intentions to get up to the Allison Rally every year, but end up at the golf course instead...Ha!

 

[RedAllison]

Darris and Glenn should be able to tell you within a mph or two what to expect out of a loaded XTB with whatever motor.

The XTB "should" be able to handle the 225SportXS ok, might have to play with the offset. I wouldn't imagine Darris would support that and I'd want to hear his opinions on it as well. But JimmyB had a 250XS on his XTB for a year or more and fished the circuits and never had a problem with the combo.

Hey I just now remembered, Darris did have a 200XS for sale (only had like 50 hrs on it). Have Glenn ask him about that motor. That would be THE perfect motor for your boat and would easily run in the 80s and get outstanding fuel mileage at the same time. He also had a 225X for sale it seemed like, that would shag-a-lag in the upper 80s for sure on your XTB (might could tweak 90ish when empty in cool weather).

One thing about the big block 225SportXS, with it's turbo diesel like torque you could prop it really tall and then cruise in the 4k-4.5k range and see 60s-70 with 6ish mpg. That would be one heck of a fishin motor, plus with its torque you'd have no problem with the holeshot. It'll push more weight than you are capable of putting in the ol XTB.

What does brother Glenn say about it?
RA

 

[ARLIN]

Glenn and Jeff are so busy right now that you cannot get a word in with either of them. Glenn has been to Memphis and Arkansas area two times moving boats just this past week. Glenn is looking good and feeling strong, hoping to keep the business in the black. Many, many Mercury dealers are going out right now due to the economic downturn.

Will chat with Nancy.

 

[Dark Allison]

That 225XS probaly has as muchpower as the old 245 carb boats and I once saw one of the them push a XTB into the 90's:twisted evil

 

[ARLIN]

That 225XS probaly has as muchpower as the old 245 carb boats and I once saw one of the them push a XTB into the 90's:twisted evil

Hey,with all the Sea Rays and such on Fort Loudoun Lake these days there are very few days now to run even my 150 at 70. I get out on Monday and Tuesday afternoons and in the Fall when UT football games take center stage. It is not usual to have a 3 foot wall of water coming at you from our homeowner's ramp any time. And, when gas was up so much last year the cruisers seemed to run extra hard for only a mile or two due to fuel cost and then shut her down--was hard to predict what their M/O was going to be and to react and Allison run accordingly. Ha!

Speaking of problems running the lakes, here is bit of feedback from Kingston TVA Power Plant ash spill site. Ironically I had put in at Glenn's place in Kingston, TN and had gone up the Emory River around the corner to get a closer look at the TVA ash spill site when my engine bit the dust. There is some obvious ash in the water all the time, but boats are passing by the spill site in the navigation channel set up by the authorities. Much shallow water in the lake part off to the right going upstream due to Watts Bar Dam being many miles downstream. Thus, boats have to go close to the spill site to stay off the bottom, especially off season. TVA contractors have lots of booms and other cleanup gear all around. 3-4 miles downstream from the spill the July 4th ECDBA drag races are full speed ahead and Watts Bar Lake looks near narmal there at the Kingston City Park area.

Getting back to my repower project---not sure what I will do to repower my XTB? May just throw on something stock in 150 and wait to see what Mercury (or others) come out with later. Ideal would be 200 Pro XS in 3.0L with some engine weight reduction to accomodate the older Allisons like mine generally designed for 2.4 and 2.5 engines. Can afford a new XB to better handle a 3.0L engine, but wonder if I would ever use it enough to justify the outlay.

...thanks all for the posts and feedback.. Allisonman, will we see you at Kingston on the 4th?

 

[Darth VMAX]

Mercury is coming out with a 200 Proxs and even a 115xs for 2010. However the 200 is still the same 3.0L that I have no doubts weighs the same as all the 3.0L mercs. might as well go with the 300 LOL.

 

[ARLIN]

Mercury is coming out with a 200 Proxs and even a 115xs for 2010. However the 200 is still the same 3.0L that I have no doubts weighs the same as all the 3.0L mercs. might as well go with the 300 LOL.

Chatted with Darris yesterday--both he and brother Glenn want me to stay with 2.5L due to weight of 3.0L engines.

Also the 200 Pro XS engines are arriving now. One Tennessee dealer emailed that they are getting 1-2 in each week, $1,000 deposit gets you a spot in line. Ha!

 

[Darth VMAX]

What about a 2.6L VMAX HPDI? I know it would be easier to stay with a Merc...just another option.

 

[ALLISONMAN]

Darth his brother would disown him if he came up with a yamaha!!!:lmao::lmao:

 

[Darth VMAX]

LOL...gotta keep peace in da family!

 

[Podge]

I have been running different motors on a XTB-21 for over 20 years. I would never put
a 3.0 litre on this boat. I believe a 2.5 - small block 200xs would be a great motor for
the boat. Just depends on how fast you really want to run..... the XTB is one of
the best handling boats ever made-but it will not handle well or be as much fun with
a heavy 3.0 motor.
.
Good luck and keep up posted

 

[Contractor]

amen to the ROLLERS on ft loudon...