1997 mariner 60 looses power

[123roger]

2 stroke/injected with 300 hours. I've replaced fuel line, bulb, spark plugs and fuel filter, drained tank and filled w/ fresh gas and marine stabil and the tank vent is open. The last 6 times out the following consistnly happens:

Runs great at full RPM's (5000) for about an hour, then suddenly dies. It starts right back up, but will only run up to about 2400 RPM's. If I try to throttle up past about 2400, it wants to quit, but keeping it around 2400 or less it seems like it would run like that forever. The last time out I had to go several miles back to the dock at the slow Rpm's and could not throttle any higher. After sitting off for about an hour it still would not go any higher. The next day the same thing repeated after running OK for about an hour.

This is very frustrating. I'm ready to buy several parts to chance at the same time or possibly take it to a mechanic for help. Problem is you need to run it hard for an hour to test!

Suggetions? Like I said, I'd buy/change the most likely.

Thanks. RR

 

[diverib]

Re: 1997 mariner 60 looses power

2 stroke/injected with 300 hours. I've replaced fuel line, bulb, spark plugs and fuel filter, drained tank and filled w/ fresh gas and marine stabil and the tank vent is open. The last 6 times out the following consistnly happens:

Runs great at full RPM's (5000) for about an hour, then suddenly dies. It starts right back up, but will only run up to about 2400 RPM's. If I try to throttle up past about 2400, it wants to quit, but keeping it around 2400 or less it seems like it would run like that forever. The last time out I had to go several miles back to the dock at the slow Rpm's and could not throttle any higher. After sitting off for about an hour it still would not go any higher. The next day the same thing repeated after running OK for about an hour.

This is very frustrating. I'm ready to buy several parts to chance at the same time or possibly take it to a mechanic for help. Problem is you need to run it hard for an hour to test!

Suggetions? Like I said, I'd buy/change the most likely.

Thanks. RR

hi did you work out the problem? as my 75 is doing something simular!

 

[CharlieB]

Re: 1997 mariner 60 looses power

You need to take a DVA meter along and test the ignition system when the problem occurs.

Stator driven ignitions having both low and high speed windings can fail once up to operating temp causing a loss of high RPM spark, limiting the motor RPM.

NEVER ASSUME an electrical part to be bad and replace it as there is NO RETURN on electrical parts, and some get expensive fast.

PROVE THE FAULT before ordering any electrical part.

CDIElectronics has an excellent Ignition Troubleshooting Guide available for free download on their Support pages, get it, study the section on your ignition, test the system cold then again when the problem occurs to prove a fault.