New BBC member and a new (to me) Xpress H51

[wheelism]

Hello everyone. I've been lurking on here for a few weeks trying to absorb everything I can about my new boat. It's a 17' 2006 Xpress H51 with a 2006 Yamaha 90 hp two stroke motor. The prop on my motor is a Power Tech VM90RED3R15S.

From my reading on this forum, it's obvious there are some extremely knowledgeable and helpful folks on here and I have a few questions. I've read that a 10" jack plate and a different prop will, after a certain amount of tweaking, eliminate the H51's tendancy to porpoise as well as increase top speed. I'm not particularly interested in setting any water speed records but I would like to increase my motor's fuel efficiency and the speed at which the boat gets up on plane. On the internet in general, it seems that the self adjusting trim tabs from Bennetts and Nauticus are popular additions. On BBC I haven't found anyone running these on an H51 even though they would be cheaper than the jack plate and prop combo. What am I missing?

Thanks in advance,
Mike

[cbr900racer22]

Hello and welcome Mike!
I have the same boat and set up as you. All stock as far as the engine goes. I am wanting to add a jack plate, turbo prop, and carbon fiber reeds but i decided to add my electronics first. Hell, I was even thinking about hanging a 115 or 150 on the back but all dreams for me right now. Anyways, welcome and nice to meet you.

Justin

[wheelism]

Thanks, Justin. A fellow Louisiana boy, I see. How long have you had your boat? What do you like most about it?

[Ranger391v]

Our moderator (Xpress Spanky) has this same boat ..... and had a 90 on it. Message him if he doesn't respond to this post. Whatever he says about it, take it as the gospel.

I do know, according to him, that a 10" jackplate is best for optimal setup. I'm sure a 6" jackplate is better than nothing.

Also, get yourself a decent prop ...... Merc Trophy, mini-Yamaha Pro Series, or mini-Raker. Probably a 17"pitch or 18" depending on which of the brands you find/get.

Good Luck!!!! And contact Xpress Spanky!!!!

[Kevin R.]

Welcome to the boards!

[Oncebitten]

Our moderator (Xpress Spanky) has this same boat ..... Whatever he says about it, take it as the gospel.

This. And congrats on the new rig. Enjoy!

[cbr900racer22]

Thanks, Justin. A fellow Louisiana boy, I see. How long have you had your boat? What do you like most about it?

I have had it for about 4 months, my Dad gave it to me. Guess the best thing is it was free! I think it is perfect size and has a lot of potential for my needs. Just wish I could go 60 mph as I am a little bit of a speed junky. I like that I can go just about anywhere in it.

[wheelism]

Ranger391v,

PM sent to Spanky. Thanks!

Kevin & Oncebitten,

Thanks!

Justin,

Free is good. You must have a great dad.
Yeah, I kind of figured cbr900racer22 might indicate a proclivity for speed. Speed is fun, just keep it safe.

[Ranger391v]

I do know that Mike/Xpress Spanky/ Spanky Clean/ GrandXpressPooBah has been really busy at work ...... and then he recently suffered a heart attack just the other week. So it might take him a day or so to get back up with you.

Rumor has it he's back at work, but they got him on Light Duty going around serving donuts to all the salesmen and pretty parts girls at the dealership.

[wheelism]

I had read about Spanky's heart problems. Sounds like he's improving and I wish him a speedy recovery. I told him in my PM that if he didn't feel like messing with me right now it was no problem.

As far as the rumor is concerned, there's no shame in picking up nothing heavier than a box of donuts for a while and who doesn't like pretty parts girls?

[xpress spanky]

Sorry for the late response,but unlike Stephen would lead you to believe there are no parts girls at work,and only REALLY ugly parts guys. Lite duty also means my regular work,and then I come home to cut up and burn some fallen trees from a small storm this last week. Now to my suggestions on your rig.A 6" plate gave my rig 3 mph,and a 10" gave me 2 more mph for a total of 5 mph gps with the same prop which was a Turbo 1 3 blade in a 17" pitch. Set prop to pad at 4 1/2" and watch water pressure.If pressure stays good work your way up to 4" under pad.Also the props Stephen mentioned like the 17" "K" series Yamaha prop and a Merc Trophy plus in a 17" would be good.The Turbo1 will be the cheapest when you buy one,and ran really good on my rig.I really think the trim tabs would kill your top end speed,but would help holeshot which can be helped with opening up the vents on the prop a little if needed. Use your powertech as a door stop.

[wheelism]

I just got back from fishing on the Ouachita river and doing a little testing. With my motor raised up on the transom as high as the existing holes will allow and trimmed down till it just quits porpoising, I'm running 37mph (gps) and 5200rpm.

Thank you for addressing the trim tab question. How much do you think they would knock off of top speed?

Is there a particular brand of (manual) 10" jack plate that you reccommend?

Got a part number for that Turbo 1 prop?

My rig isn't currently equipped with a water pressure gauge. Can you enlighten me as to where to plumb it into the motor?

Would relocating the trolling motor batteries to the front reap any benefits?

Thanks.

[xpress spanky]

The problem with both trim tabs and moving batteries forward is you'll be killing lift and creating a BUNCH of hull drag,and your speed will drop badly. You want bow lift for speed, handling,and fuel economy.With your motor up as high as you currently have it,i bet your water pressure is really low,and I don't recommend running it that high without a water pressure gauge on it.Where the gauge hooks into is with the cowl off,looking from the back it's between the top 2 cyls. on the left edge of the head.There will be a brass plug that you remove,and put the nipple in there.As far as jackplates,about anything is fine OTHER than a Rite Hite.On 6 or 10" plates,some say there steering cable is not long enough for a 10",and mine was VERY tight.As far as part number for the prop,when you order it they will get you the correct prop,and I don't have it handy or i'd get it for you.Also you might call Rothwell Marine if your ordering new,and they will fix you up,plus they are a board sponser,and will treat you good.

[Ranger391v]

Like Mike said:
- batteries up front will KILL your performance (speed and over all fuel economy).
- those manual trim tabs that adjust automatically by speed = SUX!!!!!! If you think you just have to have tirm tabs, AT LEAST get electric/hydraulic tabs. However, trim tabs are NOT the answer to you problem.


Xpress boats that porpoise are TYPICALLY a setup issue. Typically it's compounded with a TERRIBLE prop. Just b/c a prop is stainless doesn't mean it's worth a darn .... especially with all the 'general purpose' SS props out there for these mid-range HP class motors.

To begin fixing your boats porpoising issues ...... you have to:
- install a water pressure gauge (think of it as insurance ...... insurance from starving the motor of water and blowing it).
- get a GOOD prop ....... Turbo 1 17" pitch is a good start ....... if it was me, I'd look for a 17" Mercury Trophy Plus ..... or a 17" Yamaha Pro Series 'K'-series (aka mini-Pro).
- get a jackplate ....... 6" or 10" ....... Vance makes a great jackplate for the money, can be found on eBay. With that said, I also like Slidemaster. I put Vance plates on both of my Xpress boats. My Skeeter came with a Slidemaster and I liked it so much that I put one of those on my Ranger.

Lastly ..... here's a pic of my Yamaha 75/90 showing where the water pressure fitting does. Like Mike said, there will be a brass colored plug where this fitting is in the picture (notice black hose attached and ran up the port side of the lower cowling pan (mainly to keep it away from all the electrical on the starboard side).



Good Luck!

[wheelism]

Mike & Stephen,

Thank you guys for the explanations and advice. Stephen, your picture and Mike's description of the water pressure tap location are much appreciated.

Trim tabs and battery relocation are out. Faria water pressure gauge to match my other instuments has been ordered. Checking on a used 10" slidemaster jackplate. Sent an email to Rothwell Marine requesting prop and water pressure gauge fitting and plumbing availability and pricing. Probably going to need a longer steering cable.

Can't wait to get this show on the road.

Thanks again,
Mike

[cbr900racer22]

Mike & Stephen,

Thank you guys for the explanations and advice. Stephen, your picture and Mike's description of the water pressure tap location are much appreciated.

Trim tabs and battery relocation are out. Faria water pressure gauge to match my other instuments has been ordered. Checking on a used 10" slidemaster jackplate. Sent an email to Rothwell Marine requesting prop and water pressure gauge fitting and plumbing availability and pricing. Probably going to need a longer steering cable.

Can't wait to get this show on the road.

Thanks again,
Mike

Keep me posted please and I may be doing the same thing if the results are worth the $$$

[xpress spanky]

Keep me posted please and I may be doing the same thing if the results are worth the $$$

I can tell you hands down I've probably spent more money screwing with my H51 trying to pick up more speed than anyone,and a 10" plate is THE best bang for your $. It was worth 5 mph gps,a good prop will net you about 2 mph,or spend $1700 at Hydrotec for a head,tuner,reeds and rejet for 2 mph gps. That's why my boat now has the old Pro-V115 in my avatar,and I squeeze a little over 58 mph gps out of that.

[wheelism]

Got a used Slidemaster jackplate coming from a BBC member. My water pressure gauge came in today. Rothwell Marine will ship my Turbo 1 prop and water pressure gauge fitting and tubing as soon as they get some more of the props in. Still looking for a good used Mercury Trophy Plus prop.

[xpress spanky]

Good deal! Rothwell has always done me really good,and if you have a problem with something they take care of it.

[wheelism]

Good news and bad news.

Good news - Everything that I ordered/bought has come in. The water pressure gauge is mounted in the dash. The 10" Slidemaster manual jackplate is bolted to the back of the boat. The Turbo 1 prop is in from Rothwell Marine.

Bad news - My steering cable is too short and from the looks of things, I can't order just a longer cable. The steering mechanism is a sealed unit and I can't see a way to disconnect the cable from it. Looks like I'm going to have to buy the whole unit unless I can figure a way to get the housing apart. And I can't find the part number on either end of the cable. Never having fooled with swapping props before, imagine the dumbazz look on my face when I pulled the prop out of the box and saw that big squarish hole in the center of it. I didn't know I needed a hub kit for it! Got one ordered from Rothwell.

Which engine hole should I use to bolt the engine to the jack plate?