78 GT-150
Petty Officer 3rd Class
- Joined
- Jul 18, 2009
- Messages
- 79
1986 Merc inline 6cyl 90hp, mounted to a '78 Glastron GT-150...
The motor has been running great for the past few weeks. I never had a problem until a few days ago...
I went out for a few "Hot Laps" on the local waterway with a buddy. Everything was great, we were running in the high 40's low 50's. After we were done playing I slowed it down to an idle, then went back to the dock. The motor was running at a very high idle. The idle was/is at 2,000 rpm. It always idled at about 1,000rpm before the "Laps".
I run decent gas and always run TC-W3 oil.. Before I bought the boat (3 weeks ago), the previous owner ran Amsoil synthetic mixed with the gas. I don't have an Amsoil dealer anywhere around me, so I was running Polaris Synth-blend.
The motor was running just fine as always, but after a few laps I brought it into the dock. That's when I noticed the high idle.
Other than the high idle, it runs perfectly... Good/great low-end power and great top end (with my Ballistic 19" prop I am getting about 5200-5300 Rpm). No misses or stumbles, actually no problems at all. No bogs or any weirdness at all, it is just acting like the carbs are a bit open at idle.
I pulled the powerhead cover off and the carbs are fully closed. I thought at first the throttle cable was frayed and holding the carbs open a touch. But I operated the throttle lever between the carbs (by hand) and they snapped shut. So, I don't think that is the problem.
(I discovered this problem before it sunk, the sinking story is in a different thread)
Do you guys have any suggestions of what may be wrong? The neighbor mentioned something about a fast idle... A lever maybe? Something to do with the motor coming down from high RPM and this devise keeps the motor from stalling? Does that make sense?
Did I break a reed?
I know nothing about outboards or 2 strokes, this is my first one. If it were an I/O I wouldn't be asking...
One other thing comes to mind, I don't know if it has anything to do with this or not, but my fuel mileage sucks! I am burning about 6 gallons per hour at 1/4 to 1/3 throttle... Around 25-35mph at 2,000-2,500rpm
15 foot boat, 625 dry weight w/o motor, 330-350 motor weight, {2} 6 gal fuel cans, I weigh 250 and the wife weighs 95 pounds. I figure about 1450lbs maximum total weight.
Any ideas? All comments welcome! Please help!
The motor has been running great for the past few weeks. I never had a problem until a few days ago...
I went out for a few "Hot Laps" on the local waterway with a buddy. Everything was great, we were running in the high 40's low 50's. After we were done playing I slowed it down to an idle, then went back to the dock. The motor was running at a very high idle. The idle was/is at 2,000 rpm. It always idled at about 1,000rpm before the "Laps".
I run decent gas and always run TC-W3 oil.. Before I bought the boat (3 weeks ago), the previous owner ran Amsoil synthetic mixed with the gas. I don't have an Amsoil dealer anywhere around me, so I was running Polaris Synth-blend.
The motor was running just fine as always, but after a few laps I brought it into the dock. That's when I noticed the high idle.
Other than the high idle, it runs perfectly... Good/great low-end power and great top end (with my Ballistic 19" prop I am getting about 5200-5300 Rpm). No misses or stumbles, actually no problems at all. No bogs or any weirdness at all, it is just acting like the carbs are a bit open at idle.
I pulled the powerhead cover off and the carbs are fully closed. I thought at first the throttle cable was frayed and holding the carbs open a touch. But I operated the throttle lever between the carbs (by hand) and they snapped shut. So, I don't think that is the problem.
(I discovered this problem before it sunk, the sinking story is in a different thread)
Do you guys have any suggestions of what may be wrong? The neighbor mentioned something about a fast idle... A lever maybe? Something to do with the motor coming down from high RPM and this devise keeps the motor from stalling? Does that make sense?
Did I break a reed?
I know nothing about outboards or 2 strokes, this is my first one. If it were an I/O I wouldn't be asking...
One other thing comes to mind, I don't know if it has anything to do with this or not, but my fuel mileage sucks! I am burning about 6 gallons per hour at 1/4 to 1/3 throttle... Around 25-35mph at 2,000-2,500rpm
15 foot boat, 625 dry weight w/o motor, 330-350 motor weight, {2} 6 gal fuel cans, I weigh 250 and the wife weighs 95 pounds. I figure about 1450lbs maximum total weight.
Any ideas? All comments welcome! Please help!