Have a 1990 25 HP Mercury that I was getting ready for my 13 foot Boston Whaler. Had the carb rebuilt, did the annual maintenance and it seemed to be fine out of the water. Revved up nicely using the fast idle lever.
I put it in the water and took out for a test spin. It was OK in the lower revs but bogged down terribly when I applied any throttle. No power, couldn?t even get it up on plane. Checked the tank and fuel bowl for air intrusion and couldn't find any. Even borrowed a known good working gas tank from a friend but nothing changed.
At some point I thought maybe the best thing would be to get some professional help so I brought it into the shop for the mechanics to take a look at. They saw the same performance I did. So they did some basics like adjusted the timing, idle speed etc and all of a sudden it started running fine! But - the mechanic wasn't so sure that it wasn't an underlying intermittent electrical problem that caused the problem(stator, trigger, switch box). He said run the heck out of it and see how it did, bring it back if it started behaving badly again.
So I ran it home and it seemed to run great. Started right up, got up on plane and ran like a top. Excited to take the kids out for a spin, I got them out on the boat and went to start it up and it cranked but wouldn?t start. Checked for spark and got nothing to either cylinder.
I checked the various components with my ohm meter and got the following:
Trigger ? 750 ohms (acceptable range 650-850). Seems to be OK
Stator ?
B/W wire to ground ? 48 (acceptable range 120-180)
B/Y wire to ground ? 2649 (acceptable range 3200-3800)
B/W wire to B/Y wire ? 2581 (acceptable range 3100-3700)
Unless I?m reading something wrong in the service manual, the stator seems to need replacing. Values are not in the range they should be, but it is not a totally open circuit. (would a bad ground give false readings?)
Think I?m on the right path with the bad stator?
Thanks for the help guys? John
I put it in the water and took out for a test spin. It was OK in the lower revs but bogged down terribly when I applied any throttle. No power, couldn?t even get it up on plane. Checked the tank and fuel bowl for air intrusion and couldn't find any. Even borrowed a known good working gas tank from a friend but nothing changed.
At some point I thought maybe the best thing would be to get some professional help so I brought it into the shop for the mechanics to take a look at. They saw the same performance I did. So they did some basics like adjusted the timing, idle speed etc and all of a sudden it started running fine! But - the mechanic wasn't so sure that it wasn't an underlying intermittent electrical problem that caused the problem(stator, trigger, switch box). He said run the heck out of it and see how it did, bring it back if it started behaving badly again.
So I ran it home and it seemed to run great. Started right up, got up on plane and ran like a top. Excited to take the kids out for a spin, I got them out on the boat and went to start it up and it cranked but wouldn?t start. Checked for spark and got nothing to either cylinder.
I checked the various components with my ohm meter and got the following:
Trigger ? 750 ohms (acceptable range 650-850). Seems to be OK
Stator ?
B/W wire to ground ? 48 (acceptable range 120-180)
B/Y wire to ground ? 2649 (acceptable range 3200-3800)
B/W wire to B/Y wire ? 2581 (acceptable range 3100-3700)
Unless I?m reading something wrong in the service manual, the stator seems to need replacing. Values are not in the range they should be, but it is not a totally open circuit. (would a bad ground give false readings?)
Think I?m on the right path with the bad stator?
Thanks for the help guys? John
