Logo
FULL SITE MENU

89 mariner 25 hp carb problems

B

Billbachman

New member
I have a motor that idles just fine but when I either engage it into forward or just use the throttle as it has a console it revs up but won’t idle down. Turn the key off and it stays running . Choke it and it stays running. I though it was to do with my throttle cables but took the bonnet off and ran the throttle by hand and it still wants to run away. The only way I can shut it down is to unplug the fuel line and let it run out of gas. Anybody got any ideas as to what is going on with the carb? Any insight is appreciated!
 
Also it is only after the rpms are up fairly high like 4000 or so. Then when i finally kill it and start it back up it idles just fine?
 
Is this motor new to you? Sounds like your throttle cable needs adjusting. Might want to look at the wiring harness to make sure it is plugged in. If that is good I would look at your ignition switch.
 
flyingscott said:
Is this motor new to you? Sounds like your throttle cable needs adjusting. Might want to look at the wiring harness to make sure it is plugged in. If that is good I would look at your ignition switch.
Click to expand...
Yes it is new to me. Not sure on throttle adjustment if I can change it manually at the carb linkage at the motor. Doesn’t make sense when I can restart and it’s fine again by idling.
 
I might know what's wrong here, for something similar happened to mine. The early motors used the conventional method of advancing the spark by rotating the trigger coil. Later motors do this electronically, inside the switch box. Someone may have replaced the older type switch box with the newer type (that have the trigger coil mounted stationary).

Try this: disconnect the linkage to the trigger coil and fix it in position (jury rig it). Then fire the motor and let it idle. Move the trigger coil until it idles nice and slow, then fix it in THAT position. Then rev it up and see if it returns to idle as it should.

Jeff
 
So I looked in the manual to try and identify the trigger coil. As I was reading it states never to run up past a fast idle with a hose attachment for cooling as the motor may “Run Away”. I would try it in a barrel but would empty it quickly if I were to put it in gear. It seems like this could be my problem but won’t know till I can get it out on the water. Have you heard of this and does it sound likely? Use to a 4 stroke.��
 
Does the trigger stator assembly move smoothly or does it hang up. I doubt you will check that so maybe take it to a.dealer and he can show you how to operate.your motor.
 
Last edited:
Back
Top