Merc 115 Opti or EFI 4-Stroke

[delcecchi]

Sometimes a wedge to add a little tuck to the motor when it is trimmed all the way down helps. What RPM are you getting at WOT?

[gregg52]

geeez to bad i'm up at winnie alot

if i woulda read this post you coulda come up and went for a ride

i like the e-tec serves me well

power...can troll with it.. talk with no problem when troling

and runnin you can still talk

going foward it will run bout 2.5 foward on flat water

and doesnt take much of chop going backwards to put you at 1.0 or below+

now if you hafta to take in to account the boat size and weight

that makes a difference

I guess I kinda lucked out

i think the e-tec might have ran you alitte more $$$$

but i think you'd be smiling..... wife to...also if you cant see where you are going specially with kids in the boat thats not good

think saftey

you hear guys slammin e-tecs

one reason they dont have one

and think most of the problems come with the big 225+hp

as in other brands

[MikeEiden]

delcecchi I get 6000 at WOT with just me and with the wife and a couple of kids I got 5800.

Funfish, did your holeshot improve a lot with the prop change? I'm probably going to run in and pick up a lower pitch prop to try out.

Thanks to everyone for the feedback. Hope I don't sound like a whiner or complainer but I really wanted to have a motor finally that can get me and the family up on plane fast without having to plow water.

[delcecchi]

6000 sounds right. My money is now on mounting height and weight distribution. And try the wedge. They are cheaper than all those props. :-)

[gregg52]

JUS..CHIRT This is bunch a [PoorWordUsage]

spend 7k and everybody is saying do this and that ????????????

something is wrong here !!!!!!!!!!

I'll be on Winiie this week end

put these guys on hold

I'll take you for a ride

[delcecchi]

JUS..CHIRT This is bunch a [PoorWordUsage]

spend 7k and everybody is saying do this and that ????????????

something is wrong here !!!!!!!!!!

I'll be on Winiie this week end

put these guys on hold

I'll take you for a ride

Well, if he wants to sell the merc to help pay for the etec I might be interested. I have seen a lot of 115 4strokes running around vermilion and they seem to work just fine.

[gregg52]

i guess i'm not saying its

not an ok motor

but it just doesnt fit his needs and the salesman kinda decieved him

to make the sale

and its just underpowered

where as the e-tec would have served his purpose better

and like i said he might have be albe to go up to 125 not sure what his boat is rated for

in my opinion another 1000-1500 on a purchase like that...something you going to have for awhile is well worth it

and also a saftey issue if he is plowing water like he says

[311Hemi]

Mike,

Out of curiosity, how does your hole shot compare to the video I posted below? I get by just fine with the performance of my F115 on my 18', which I would assume the F115 would be very similar in output. I obviously have better holeshot when not towing up a skier and having less weight in the boat....I was fairly loaded down.

http://www.hotspotoutdoors.com/forum/ubbthreads.php/topics/2277703/3/90hp_vs_115hp

And to anyone who says a prop change wont help, a prop can make a big difference. Also, a 17' boat would not really be that underpowered with a 115 4stroke. I run one on a 18' and it does just fine even when loaded down, no issues with holeshot. Would I consider it underpowered, yea probably because I can only do 38 mph. But it performs just fine everywhere else.

Sounds like something is not right with this setup.....mounting, prop, hull, something. What prop were you running when you tested this last?

My boat had an 17 pitch aluminum hustler on it when I bought it and it did not perform very well. I picked up a 16 pitch SS Power Tech prop and it made a big difference in my performance (made no real difference in speed).

[Dale Rueber]

delcecchi

Funfish, did your holeshot improve a lot with the prop change? I'm probably going to run in and pick up a lower pitch prop to try out.

The primary reason I changed to the lower pitch was to improve the holeshot, that is also why I went to stainless. The hole shot was very, very poor when I had another person in the boat and the rear livewell filled. Your full throttle RPM range is 5800-6400 so it looks like you have a few RPM to play with. Try running the prop selector on the Mercury Marine web page to see what it comes up with.

My hole shot improved dramatically. Now with 3 adults and a full rear livewell it will get up on plane easily. It does not jump onto plane but does fine.

[311Hemi]

JUS..CHIRT This is bunch a [PoorWordUsage]

spend 7k and everybody is saying do this and that ????????????

something is wrong here !!!!!!!!!!

I agree something is wrong, but I disagree that him going and buying an e-tec will cure his issues. You got lucky and had someone prop your boat correctly from the get go, many people are not that fortunate. Your e-tec didn't come from the factory with a prop on it, the dealer installed one that they thought would perform best on your boat. Had they selected the wrong one you could end up with bad performance that eve the e-tec may not overcome.

I like e-tecs, heck my dad has one and it's a great engine......but you need to relax with it being a cure all for all boat performance issues.

[311Hemi]

The primary reason I changed to the lower pitch was to improve the holeshot, that is also why I went to stainless. The hole shot was very, very poor when I had another person in the boat and the rear livewell filled. Your full throttle RPM range is 5800-6400 so it looks like you have a few RPM to play with. Try running the prop selector on the Mercury Marine web page to see what it comes up with.

My hole shot improved dramatically. Now with 3 adults and a full rear livewell it will get up on plane easily. It does not jump onto plane but does fine.

I agree, Mike.....IMO you need to try a 3 blade stainless steel prop and try to get your max RPM's close to the 6400 rpm range. I think a 17 pitch Power Tech or similar brand may be a good starting point. Just make sure you get it from someone that will allow you to swap out for another prop if it does not get you the performance you need. I had to try 4-5 different props to get mine dialed in to where I wanted it.

[MikeEiden]

Hemi311 thanks for posting that video to compare to. The recent prop on there is a Solas 17" aluminum and my take off by myself was an improvement; but maybe slightly slower than your video. Hard to tell but I think I get a little more bow rise. I'm finally seeing a little light with this last change. I'm going to call T&M in a few minutes and see what suggestions or ideas they have from here. Plus I still owe them for this prop if I were to keep it; don't want to get that nice kid in trouble!

I'm going to try and get out with the kids for an hour to test the boat with more of a load. I'll try and get some video.

What RPM are you guys able to cruise at? Maybe I'm thinking to much along the lines of 2 strokes and thinking I can cruise at 4000-4200rpms. I just hate to sit and wind this thing up everywhere I go.

[MikeEiden]

Ok, just got off the phone with T&M and they had been looking into ideas. One thing they noticed is they measured my old motor length with the bracket and there was a little difference than this motor/bracket. The old one is slightly longer. Because I have no trim available and with everything happening he mentioned the wedge idea to try next. He said it will move the motor back some and changing that angle will give me more avaible trim. Then he's going to give me a handful of props to try out. Because of the my WOT rpms being around 6000 the option of a 15 or 16 pitch may also be an option. So it sounds like I'll be playing around for a while today.

Thanks for all the help and really the reassurance that there is hope for my new purchase.

[311Hemi]

Mike, keep in mind that video was my Yamaha 115 4 strk on a 18.5' Crestliner with the following: 4 - 200 lb adults (one being the skier), 3 - 60 lb dogs, 39 gallons of fuel, and 3 batteries located in the rear of the boat. Plus, the engine bottomed out in the mud if you look closely in the video.

With just me in the boat it has much better hole shot than in that video.....it should not be any slower with your 17.5' boat and certainly not longer. You really need to try a stainless prop and I would start with a 17 pitch, but have a 19 and 15 handy if they will let you. They are definitely worth the investment.

I am able to cruise at any RPM I feel necessary, engine should not have anything to do with that IMO. My normal is around 4000-5000 rpm's, but I don't have the proposing issues you due.

[BoxMN]

+1 on Hemi's advise for the SS prop. 2 or 4 stroke, once you get to the around 100hp mark, it does make a difference, a noticable one. Good luck! Will be watching, as you will be happy once it is all dialed in. Sometimes it takes a bit of tweaking.

[delcecchi]

I did a little research on the net, and it sounds like the two variables you have control of are weight distribution and prop selection.

The big variables in prop design are rake and cup (not counting pitch which really isn't a design issue). I think if you try props with more or less rake you might find a pattern.

I have been trying to think why a new motor with more horsepower would have trouble getting up on plane and would porpoise. I can come up with three possiblities. Others have said the same thing btw.

Weight distribution. The new motor is like 100 lb or more heavier than the old one.

Trim/Transom angle. Maybe the motor is trimmed out a little more than the old one when it is all the way down. You want to see my boat have trouble getting on plane, watch me when I forget to trim the motor down before taking off.

Prop Rake. The new prop has too much or not enough rake. I'm not smart enough to know which.

Good luck.

[MikeEiden]

Alright here's the latest. Did a few prop changes today and the dealers mechanic came out on the water with me.

As for the porpoise that stayed the same no matter what prop we tried. Either the info got changed between people but he was under the impression that it would do this fully trimmed in. I was able to get it to do it each time. He said its just the hull design that can't handle that slow of speed and trimmed out any. So basically I have to run 5000rpm or higher if I want to trim out any and have decent cruise speed. Never did it with my other motor but I don't think it lifted the boat out of the water as much as this one. So maybe that's the difference.

The first prop we tried was a 15" Aluminum. Now this was the hole shot I expected! It was another huge jump in performance but I really lost top end. Ran a max of 36mph at 6400rpm. Even cruise speed was around 5500 and only 26-27mph. This acted more like your boat in the video Hemi out of the hole.

Next we tried a 15" SS prop thinking I could gain some top end back. This was worse out of the hole than the aluminum with the same top end.

It doesn't say how much or really the difference but that Solas aluminum prop says it has more rake to it so maybe that's the difference.

So for now I just purchased that 17" Solas. It had a decent hole shot but I was able to run 41mph @ 6100. And cruise around 34mph @ 5000. Maybe a 16" or 17" SS will give me more performance yet but I've tried a lot of props and may take a break for a bit. I'll see if anyone locally carries Power Tech props Hemi and give them a try. It would be nice to have a "one-prop-fits-all" but I may have to purchase a 15" for heavier loaded days. We don't do water sports really so that's why I went with the 17".

Well an Opti may have been a better choice for me but this motor is looking better each time out. Really started off rough and sluggish but the performance is much more closer to expectations.

[gregg52]

I agree something is wrong, but I disagree that him going and buying an e-tec will cure his issues. You got lucky and had someone prop your boat correctly from the get go, many people are not that fortunate. Your e-tec didn't come from the factory with a prop on it, the dealer installed one that they thought would perform best on your boat. Had they selected the wrong one you could end up with bad performance that eve the e-tec may not overcome.

I like e-tecs, heck my dad has one and it's a great engine......but you need to relax with it being a cure all for all boat performance issues.

I'm not the relaxing type........loL

The Etec may not be the answer to ALL problems but in this I think it would have cured 99.5%

Plus as someone said that 115 coulda be the much heavier it cant get out

of its own way...lol

where as he might have been albe to bump up to a 125 (not sure bout that)

I gues I've been lucky on 3 occassions then the current boat I have

and my old boat and the new e-tec i put on the old boat

never no monkeying around with props after the purchase

could be this dealer may not be the best I dont know

I hope and it sounds like hes gettin it worked out so hes happy

7k is good chunk of change

[MikeEiden]

Gregg, I gotta say I always appreciate the "enthusiasm" you put into your posts! As for motor sizes I could go up to a 150 on this boat and trust me I thought about it for a long time.

I thought this was a pretty typical installation being there are a ton of 17' boats with 115's on them but after the rough start with the 4 blade and then how the 19 3-blade performed I thought I had made a huge mistake. That 19 was giving me 6000 WOT so I didn't think there was much room to move without sacraficing my topend by over rev'ing.

I'm hoping I can eventually find the combination that will give me both that hole shot I desire and keep my 40-41mph and higher cruise speeds. I have friends with older EFI 2-strokes and similar boats and loaded down they get right up on top out of the hole and they have great topend. So that's what I've been comparing to.

I'll let you guys know if I tinker around more with the set up and how it performs. If there are any more suggestions I'm always interested in hearing them.

[311Hemi]

What SS prop was it that he brought with for you to test, cause it does not sound like it did all that well? The proper SS prop should get you better performance than an aluminum, but only if they use one designed to achieve what your trying to do. Props obviously have different designs.....did he grab any one for a specific reason? Some are going to perform much different than others.

I would say you are correct that 115's are fairly common on 17', heck a lot of 18' have them as well (even though they may be a bit underpowered for the boat) based on max hp ratings.

I think you should give Jay at Soderbloom Props a call (I think a forum sponsor) and describe your setup. Have available to exact prop make/models you have tried and the performance you achieved with them and see what he says. You may have to wait a few days for the prop to be shipped/exchanged but it may be worth it in the end to get the correct prop.

You have tried raising and/or lowered the outboard, right?

[MikeEiden]

I'm not sure what brand SS prop that was. They didn't think they had one in the 15 pitch until they found a used one. So it was just grabbed for no specific reason other than to try a SS 15". I think it was a little larger diameter once I seen it on the motor. Much closer to the plate than previous.

I wish they would have sent a 17 SS with just to try it. Each time they would install a new one I would then have to drive back out to the river or Pokeg and unload to test it out. It gets old after 2-3 times so I wished they just brought a few extras. From the sounds of it most of you guys are able to get closer to the 'best of both worlds' so I'm still hopeful for even more improvement.

I've been holding off on ordering props just because of these mixed results I get. I'll get a hold of that person you mentioned and I am also going to get some peformance measurements for the Power Tech. Checked out their HSOforum and it seems like a good place. Maybe its time to take it out of the hands of the dealer and put in the hands of some prop experts.

We did not move the motor at all. We can not go down at all; only up from there. I'll try and figure out how to post some pics of the motor height. I'm sure most are curious to say the least.

[311Hemi]

Mike, email me at zach***ej1@hotmail D0T com

(remove the *** from the email address)

[311Hemi]

Here ya go Mike:

Trimmed in:

Trimmed in (2):

Quarter trim out:

Trimmed in:

[gregg52]

i have a trim gauge that tells me what per cent i'm at

dont excatly how it works but i love

its very handy

i dont know if they can be added or what

but its sweet

i dont know if they are on most boats or not