Top End Speed

[Big dreams]

I have a 99 TR20 with a Merc 200, 6" manual jackplate, and a 25P Trophy prop.  People with the same exact setup on BBC state they are running low 70's.  My motor has a fresh rebuild with 7 hours on it so I might be jumping the gun here.  After 5 hours, the mechanic told me I could open it up for 2-3 second bursts.  When I did this, the top speed I can get to is 56 mph at 5500 rpm.  I am running 100:1 oil mixture on top of what the oil injectors are pumping for the break in period of 10 hours. 

To me it seems I would at least get up to something close to 70.  Any ideas?

[Baybass]

I know that boat and when you get the motor broken in you should be high 60's with dialed in just right 70.   But wait till it's broken in......don't worry about speed yet.  Oh, and don't forget ethanol additive....

[Big dreams]

That is what I was thinking but was beginning to wonder.  A few more trips out and she should be broken in.  I just put the last of the 100:1 oil/fuel mix in.  The reason for the rebuild was due to the gas line inner falling apart and getting into the motor.  What kind of Ethanol Additive do you all use?

[Revtro]

I'm sure it'll get up there after the break-in, I had a similar experience.  But remember a couple of things.
1. People like to exaggerate their top end speed.  Some might call it overcompensation.  LOL
2. They do their speed tests with no extra weight in the boat, no gear, not much gas, etc.

Real life top end speed is never what people "clock" it at.  Heck, how often can you do top speed on a lake anyway?  I fish LSC all the time, and conditions rarely allow for me to be wide open without killing myself.  In real life, we tend to run lower than top end most of the time.  But I'm sure that rig's gonna kill it when the break-in is over.  On those extra calm days, it's gonna be fun! 

I use to use Ring Free.  Lately I use Merc. Quicklean.  Works pretty well.

[Big dreams]

Mercury Quick Clean will help with ethonal?  How often do you use it?  Should I use it on the break in or wait untill the 10 hours is up?

[Baybass]

Not to mention, don't get to hung up on speed.  Seems like in touny's it's always the guy who is fishing on just the Trolling motor because blew an engine that do well.  Makes them slow down and fish the water in front of you instead of blowing around the lake at 70mph...

[River Rat]

I don't know about the top speed set-up for your rig but will say that the Mercury Quicksilver products are excellent. They have 3 "steps" but the first two are important here: Step 1 Quickare is for treating the ethanol in our gasoline, and Step 2 Quickleen is to help reduce/prevent carbon deposit build-up that result from the 2-cycle burn. Some think it's not a justified expense but who the heck said these rigs are cheap to run?

Just my 2 cents...

Scott

[Big dreams]

All good information.  I am looking into purchasing the QuickSilver products now.  What about applying wax to the bottom of the hull to help it glide across the water? 

[Bender]

I have always been told not the wax the pad. You can wax the rest of the hull but if you wax back there it will create suction and actually slow you down. It sounds to me like you might need to raise your jackplate. Not sure if you have set it yet but I keep raising it until my water pressure drops when trimmed out and running, then drop it back down a notch. Do you know where it is set right now?

[Big dreams]

Is there a way to read the jackplate?  I know when I am on it, the water pressure is up over 30.  I checked both sides of the jackplate and did not see any markings on measurements.  I must be missing it as it seems like it would be a must for those.  Any idea where to check?

[Anthony Adams]

Tritons run best at around 3" below pad. Top speed on that rig in a lighten mode, little gas, no tackle, one person in boat you can break 70+. In real world mode 1/2 tank gas all your gear and a buddy next to you. 63-67 max depending on the load.

Run quickcare in every tank. Run quickleen twice a year or more. Run quickstore on your last tank of gas for the season.

I recommend an in line water separator / fuel filter to help with the ethanol and break down issues that caused the motor to blow.

Hope this helps.

If you have more questions about set-up call me at colony marine 248-371-0 four hundred.

[smbassman]

You mention 99 and merc 200.  If it is a 3L opti - 70 might be possible. With an EFI (2.5L) you won't ever be far above 65.  Not sure if I have the years right, but I thought the TR20 was a 225hp rated boat which would push it into the low 70s.

[Big dreams]

It is a '99 Triton with a '99 Merc. 200 EFI.

[Anthony Adams]

Actualy the EFI's were slightly faster than the opti's in most cases. The PRo XS is a different story.

[Bender]

Any idea where to check?

I hope it's O.K. with Dan to link to another board, but click here to see an illustrated method for getting this measurement. 

[bigjc]

  When I did this, the top speed I can get to is 56 mph at 5500 rpm. 

To me it seems I would at least get up to something close to 70.  Any ideas?

I am certainly no expert, but it would seem that you should be turning more than 5500 R's.  Might be a jack plate adjustment.  When adjusting the depth of motor in the water, remember an 1/8 of an inch makes a huge difference.

[Revtro]

I'm kinda thinking that once you start running normal after the break-in, things might pep up.  If not, maybe you need to change your plugs.  I did this immediately after the break-in on my motor and it made a huge difference. 

[fish hound]

Get it totally broken in first.  Then see what it's got without all the extra oil etc.  Then check your prop to pad as Bender suggested.  What is the gear ratio on your LU?  The slip calc even at a 2:1 gear ratio shows a 17%+ slip, more at a 1.75:1 or 1.87:1.  And yes, a lot of guys post the max speed they have ever seen with no batts, no gear, and running on fumes.  We all know that doesn't matter.

Matt

[Big dreams]

I am not sure what the lower unit gear ratio is.  I will have to check into that.  As far as plugs, what do you all prefer?  I know there are a lot of different types/brands out there.

From what people post on their top speed, I was thinking the motor was not running correctly since there is a 15 mph difference but from what you all say, that is normal.  Makes me feel better!

[Waterfoul]

As others have said, your top end will get better as you break the motor in and start running the proper fuel mixture.  I just finished the break in on my rebuilt 150 EFI and it's about 2-3 mph faster than it was just a couple weeks ago (at the beginning of the break in).  First tank of straight fuel in it now.  Smokes less too!!

As for pad height... 3" below is about right... you don't want that water pressure to fall below 10-12 PSI at wide open... or have the needle "bounce" when running top speed.  You can experiment with the jack plate.... 1/8th inch at a time!!

According to all the tests I've seen, the best rated ethanol treatments are the Stabil Marine (looks blue in the bottle) or the Valvtect product (green bottle).  Personally I run the Valvtect.