Yam Ft9.9 Igntion

DHPMARINE

Captain
Joined
Dec 16, 2003
Messages
3,688
I'm having trouble diagnosing an ignition problem on a 1988 Yamaha 9.9. It's a FT9.9ELG.4 stroke.

Sometimes it will run fine,but sooner or later it acts up.It is the same as if I were hitting the kill button rythmically.Just like pressing it in and releasing it over and over again.

First guess was the CDI,but the new one does the same thing.

I found the coils and magnets lightly coated with rust,cleaned them up,same thing.

I'm looking towards a new Pulser Coil,but really don't know how to test it. (I know the factory manual will be suggested,but we can't buy the manual
for ever motor traded in here).

Any Ideas ?

DHP
 

bgbass.1

Chief Petty Officer
Joined
Aug 1, 2007
Messages
558
Re: Yam Ft9.9 Igntion

I had one doing the same thing it was getting hot but not hot enough to trigger the alarm ended up being thermostat
 

DHPMARINE

Captain
Joined
Dec 16, 2003
Messages
3,688
Re: Yam Ft9.9 Igntion

that's a thought,but this one is running at OK temp.Thanks.

DHP
 

sdsaw

Petty Officer 2nd Class
Joined
Aug 19, 2007
Messages
188
Re: Yam Ft9.9 Igntion

This may be a long shot, but try changing your oil and make sure the oil filter is clean.
My 9.8's oil tank corroded thru and dirtied up the oil causing it to lose oil pressure and then the timing will retard (safety feature) causing the motor to run real poorly.

Scott
 
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