1998 60 horse yamaha

tdubb123

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Jun 29, 2012
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have a two stroke 1998 60 cranks idles great and will typically run perfect bout five to ten minutes until heats up the if get over about 2500 rpm it will skip u could say sounding like rev limiter or something wah wah sound but still continues to crank idles fine ect thought it was coils and replaced them was told change therostat and water pump but peas good carbs and fuel lines just redone but sat up long time what could it be maybe cdi but what are signs that is expensive troubleshooting any ideas
 

99yam40

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Sep 7, 2008
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8,851
Re: 1998 60 horse yamaha

As with any motor when starting to test.
Compression, spark, timing, and fuel pressure/vacuum
If all is in spec then go through the carbs , especially since it has set up for some time

Timing can be retarded due to CDI seeing a problem with overheat or low oil level so make sure you test at problem RPM also
 

shackle101

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Jan 11, 2012
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Re: 1998 60 horse yamaha

Did it start doing it after the carb rebuilds? Could be the carb linkage set incorrectly.
 

tdubb123

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Re: 1998 60 horse yamaha

Was doing the same thing before carbs redone but hate to just replace CdI if not sure can get expensive
 

99yam40

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Re: 1998 60 horse yamaha

why not test things like I said.

If you have a problem with spark you test inputs and outputs of CDI to see if it is the problem.

Do you know if you alarm system functions properly?
That can be tested also
 

tdubb123

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Re: 1998 60 horse yamaha

ok have come to conclusion that spark and spec of ignition system is good motor seem to be overheating and going into a protective mode or hitting rev limiter triggered by cdi pees fine how ever water gets very hot thermostat looked very coroded took it out and ran it to see if would still over heat and did however no alarm sounded and not hot enough to steam or anything drastic just hotter than should be but of course ran long enough until these symptoms began going to order new water pump and thermostat if that isnt the problem what is next step ?
 

99yam40

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Re: 1998 60 horse yamaha

how did you come to this conclusion?
Have you tested any thing?
 
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