Nitro 591 w/135 optimax

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Michael Rager

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I just bought a Nitro 591 w/ 135 optimax. Took it to Truman Lake Mo the other day....had some question that maybe someone could help me with.

The Mercury webpage lists the 135 opti with a 5700 WOT max RPM. I took it to that and didn't even have the motor trimmed. I asked the dealer and he said that the new optimax's have an computer on board that will start automatically throttling back if you exceed max RPM.

Questions:

A) Does anyone know what I can take it up to without damaging the motor?

B) Is the dealer correct about the computer throttling back after redline?

I had it up to 62 MPH while trimming up to about 6250 RPM anything after that the boat started teatering on a glass lake.

Prop is a 25 pitch Tempest and I think it's 14 1/2"

The boat handled like a dream and I only have one complaint so far which has to do with the trolling motor pedal recess bank. In chop the pedal bounces right out of that slot because the wire coming out of the front of the pedal pushes it up, but once i turned the pedal around 180 degrees...so the wire faces the back of the boat it did ok.....still think I will put a velcro or rubber strap across it to keep it in place. I will post some pics when i get a chance.

Can anyone give me some guidance please so I'm not so worried about burning up my motor?



tks

Rags

 
The one they gave me at the dealership was not to stay at any given RPM for too long. 10 or so seconds per RPM reading was what I did during the "Break in period". here it is 9 years later and it still starts on the first try and still hits the 70 mark.



Max <><
 
First thing I would do is take it back to the dealer and have the tach checked out. The rev limiter should kick in at 5800rpm. If the tach is OK then Merc has changed the limiter on the Optis.
 
My recessed pedal is screwed down. Couldn't you do the same?
 
Right off the Mercury Web Site:

Specifications

HP @ Prop: 135

kW @ Prop: 99.2

Max RPM (WOT): 5000-5600

Cylinder/Configuration: V-6 (60 degree vee)

Displacement (CID/cc): 153/2507

Bore & Stroke (in): 3.50 x 2.65

Bore & Stroke (mm): 89 x 67

Cooling System: Water-cooled w/ thermostat & pressure controlled

Ignition System: PCM 038

Starting: Electric

Gear Ratio: 2.00:1

Gear Shift: F-N-R

Steering: Remote

Alternator Amp: 60 (belt-driven)

Alternator Watt: 756 (belt-driven)

Trim System: Power trim

Exhaust System: Through prop

Lubrication System: Electronic multipoint oil injection

Recommended Oil: Mercury OptiMax/DFI Engine Oil

Fuel Induction System: 2-stage direct fuel injection

Shaft Length (inches): 20/25

Shaft Length (mm): 508/635

Dry Weight (lbs.): 431

Dry Weight (kg.): 195

Operator Warning System: Overheat, low oil level

SmartCraft: Yes

CARB Star Rating: 3

Warranty: 3

Counter Rotation:
 
An alarm will sound if you reach the max RPM. I agree with the others, have the tach checked.
 
I had the over rev limit on my 200 opti, it alarms, but did not throttle back, changed prop all is well.......read your owners manual on break in, mine said not to go wide open for more than 10 seconds during break in
 
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