HELP!! 2000 200 Opti... WHAT NEXT?? DON any ideas?

[wabassguy1]

2000 200 Optimax
OTO14422
450 ish hours

Long story short

At WOT I get a slight hesitation, noticed it about 2 months ago and started doing some research. Talked with local shops and both recommend new plugs.

What it does: Only time I notice anything is wide open about the time I am getting to top RPM/Speed (5700 ish/65mph). It feels like I am slightly taking the pressure off the hotfoot for just a sec. Only way I can really describe it. No sound difference, just the hesitation. Even my co angler has noticed it and can feel it. At one point it got so bad that I dropped about 6 mph and was losing rpms. I stopped it running it asap.

I have had this boat bout 7 years now and when I first got it this happen to me every now and then but then went away for about 5 years with no issues.

All parts are replaced with recommend replacements per European Marine
Have run NON Ethanol fuel and the Don cocktail for about 5 years now.

What I have done, replaced and checked


Cleaned and check all battery connections
New plugs
Fuel lines from tank to diaphragm pump
Fuel Bulb
Rebuilt diaphragm pump
All new lower unit seals
Water pump

Checked fuel pick up in tank
Checked Tank vent
Checked all coil pack plugs and wires to plugs

After doing all this I had it out Sat and it ran great, no hesitation that I could feel, ran to several spots and seemed great.
Sunday I went out and was getting that slight hesitation again.. GRRRRRRRRRRRRR.

What is the next thing to check, any recommendations. I am really at a loss of what I can do next.

Only thing I can think is I did put a new battery in this winter/spring and then noticed it happening. (Northstar 31 AGM CCA 1150 MCA 1370) I will take battery in today and get load tested.

Thank you all

[06 SB]

The first thing I would do before spending anymore on parts would be to take it to a dealer to have the fault history printed out.

I am not familiar with the alarm logic on that year Optimax. It could be you are hitting the limiter. My 2010 200 ProXS limiter would give me an alarm when hitting it but my 2004 115 would not. It would do exactly what you describe.

[wabassguy1]

06 SB.. I did have it in and no faults at all. :(
I have hit a limiter in my old boat and know that feeling pretty well. Also I am set up pretty good and watch RPM very close and when it happens its well under the listed max rpm of 5750.
Gotta say this is driving me nuts.

Thank you for the suggestion.

[06 SB]

Good to know. Hopefully Don, Savage or Joe will jump in.

I'm not sure if you know this but the "5750" is not a hard number. There is a window based on many conditions. I've had it kick in as low as 5600 RPM.

[wabassguy1]

06 SB did not know that!! Interesting will have to look into that more. What is killing me is nothing has changed on boat, have not taken weight out or added. Same prop for the last 3 years, etc etc etc. Also the fact that I have lost some speed. Went from running 63-65 to 59-60.

[Savage]

If the problem comes and goes, then the issue is probably electrical. Perform a spark test as the problem is occurring.

[wabassguy1]

It has been very constient for the last month. And not sure how I would do that either? Any videos, etc I can check out??

[vicsservice]

[QUOTE=wabassguy1;9372427]

2000 200 Optimax
OTO14422
450 ish hours

Long story short

At WOT I get a slight hesitation, noticed it about 2 months ago and started doing some research. Talked with local shops and both recommend new plugs.

What it does: Only time I notice anything is wide open about the time I am getting to top RPM/Speed (5700 ish/65mph). It feels like I am slightly taking the pressure off the hotfoot for just a sec. Only way I can really describe it. No sound difference, just the hesitation. Even my co angler has noticed it and can feel it. At one point it got so bad that I dropped about 6 mph and was losing rpms. I stopped it running it asap.

I have had this boat bout 7 years now and when I first got it this happen to me every now and then but then went away for about 5 years with no issues.

All parts are replaced with recommend replacements per European Marine
Have run NON Ethanol fuel and the Don cocktail for about 5 years now.

What I have done, replaced and checked


Cleaned and check all battery connections
New plugs
Fuel lines from tank to diaphragm pump
Fuel Bulb
Rebuilt diaphragm pump
All new lower unit seals
Water pump

Checked fuel pick up in tank
Checked Tank vent
Checked all coil pack plugs and wires to plugs

After doing all this I had it out Sat and it ran great, no hesitation that I could feel, ran to several spots and seemed great.
Sunday I went out and was getting that slight hesitation again.. GRRRRRRRRRRRRR.

What is the next thing to check, any recommendations. I am really at a loss of what I can do next.

​I don't see a fuel filter on your list?

[wabassguy1]

​"I don't see a fuel filter on your list?"

It is on the way. It was done last year about this time. Will get it put on here this weekend and run it to see if that changes anything.

[Nova Kaw 650]

06 SB.. I did have it in and no faults at all. :(
I have hit a limiter in my old boat and know that feeling pretty well. Also I am set up pretty good and watch RPM very close and when it happens its well under the listed max rpm of 5750.
Gotta say this is driving me nuts.

Thank you for the suggestion.

Did you instruct the dealer to just check for codes, or to troubleshoot the issue?
I would think it's time to start with testing air and fuel pressures, as it's an 18 year old motor.

[abs988s]

I see you changed plugs, but what about plug wires? My ‘02 200 Opti was having what sounds like a similar issue at higher rpm’s and I found that a plug wire was not firmly attached. It was the #1 cylinder which is on top, so simply putting the cowling back on can potentially drag on that boot and pull it out some. However, after 16 years of taking them on and off to check or change plugs, they can get a little worn out and lose their “snap”. My mechanic changed them this spring and no issues so far.

[wabassguy1]

I see you changed plugs, but what about plug wires? My ‘02 200 Opti was having what sounds like a similar issue at higher rpm’s and I found that a plug wire was not firmly attached. It was the #1 cylinder which is on top, so simply putting the cowling back on can potentially drag on that boot and pull it out some. However, after 16 years of taking them on and off to check or change plugs, they can get a little worn out and lose their “snap”. My mechanic changed them this spring and no issues so far.

Have not done wires but crossed my mind. I did take them off and inspect them and they seem to snap on pretty good and tight. No real change in anything.

Thinking after fuel filter I will grab a coil and wires and start going that route as well.

I am starting to think its either the fuel pump (not diaphragm) or electrical like coil or wire.

Nova Kaw 650 - I did have him run the whole thing for any faults that it could show but was in the shop for that reason. Had it in for oil pump prime, lower unit and just a general look over.

[EuropeanAM]

Wires, proper plug gap, are you pumping the bulb firm before EVERY SINGLE engine start, and is there ANY (even the slightest) prop damage?

What prop are you running?

In regards to changes- what battery did you have previously (you indicated you've recently put a battery in).

[wabassguy1]

Wires, proper plug gap, are you pumping the bulb firm before EVERY SINGLE engine start, and is there ANY (even the slightest) prop damage?

What prop are you running?

In regards to changes- what battery did you have previously (you indicated you've recently put a battery in).

Thank you for the response.

So to clarify the issue was happening before I did the above maintenance as well as after.

Plugs gap is correct, I even took them out to check. Wires are a few years old and have not been changed as of yet. I do prime the bulb before all starts (this is newer to me and started doing that this year)

Prop is like new condition 23 tempest (I am way to OCD to have any nicks on my prop!! lol) I also have a 24 Fury 3 blade as back up.


Battery I took out was a Interstate 24XHD Starting 1000 mca 800 CCA (was only for the motor, graphs and accs. were run on another battery). Tested out above stated specs but after getting new graphs I wanted to run everything off one battery. Currently running Northstar 31 AGM 1150 CCA and 1370 MCA. Also motor wires are on a clamp style and accessories are on threaded lug.

Taking battery in now to get load tested, If comes back bad will update on here. ***UPDATE*** Battery checked out above listed stats on all levels.

As far as the battery goes.. I kinda feel like this started after I changed batteries.. but not 100%. I had no issue while I had the Interstate as the main battery for the last year and half

Also fuel lines, diaphragm pump bulb all looked great but still put all new on it. fuel tank pick up is clean and free of crude although I did see some floaters in the tank but very little.

[EuropeanAM]

Let's explore your battery "hunch". Move ALL of your wiring to the clamp posts (engine cable FIRST, remaining lugs largest to smallest, wrench-tight nut or locknut).

Also, think back and compare total battery weights/placements (that may have been a change not considered)?

[wabassguy1]

Let's explore your battery "hunch". Move ALL of your wiring to the clamp posts (engine cable FIRST, remaining lugs largest to smallest, wrench-tight nut or locknut).

Also, think back and compare total battery weights/placements (that may have been a change not considered)?

Done!! Will run this week and see what happens.

As for battery weight I had 2 24 series in that spot before. Now just the one 31 agm weight is very similar and in same spot

.

[lpugh]

Make sure the rubber boot in the air box that slides onto the throttle body in place properly, I have this happen before where part of it is inside the throttle body mouth. Also open the throttle and look inside the plenum for foreign objects.
I would also find some one that has a DSO/lab scope and scope test the TPS sensor concentrating on the throttle position in which the problem occurs. I have seen many tps sensors fail that you could not detect with a DVOM, warm it up with a hair dryer while testing it. WARNING: do not heat so much that you can not keep your fingers on it
Most any good automotive tech experienced in drivability can do this for you if your local marine techs can not. This is not something the average mechanic can do. I using a auto tech, Ask if the tech that is going to perform this test has a L-1 Advanced ASE certification, if they don't find one that does. Mercury techs probably would not have this certification as Mercury techs are Mercury trained and some would have Mercury Master status and ASE is for automotive. This sensor operates in exactly the same way as a TPS on most Autos
I doubt in my area there is Marine tech that even knows what a DSO/Lab Scope is, little on how to intrepid the waveforms. Or you could just replace it which might be less than the cost of testing it correctly.

[SilverFox579]

Brian used the same Mercury Master certified tech I do. He's top notch and the only Mercury tech that gets to touch my engine besides me.

[wabassguy1]

Thanks Leon. Will check that soon as I get back home and look into TPS

[wabassguy1]

SilverFox579 only one allowed... well besides me!! Lol I have had him on the phone a few times. Need to get back in there if I don’t get it figured out