Andrew Bienhaus
Cadet
- Joined
- Sep 2, 2016
- Messages
- 6
Good Day all, and thanks for ideas, in advance!
I got to this forum via Google, with hits on similar challenges with the same motor, but none of the posted solutions so far, seem to have cured it. :-(
So, here we go... as requested, fresh posting.
1985 Yamaha F9.9SK 4 stroke
I don't have a lot of history on it, but in efforts to repair and get rolling again, here's what we have done.
There was no spark, so I used a voltage adapter and DVM, to diagnose "bad CDI". Managed to get a used CDI, matched up all the wires, and we have spark and life!
Carb got well cleaned out before that, and jets are clear.
Took some priming, and had to push some oil out of the exhaust (probably was stored improperly) and got it fired up and running.
Good stream of water from the one jet. (is the second jet supposed to be squirting? or is it some sort of overflow?)
Got it on the boat, and went for a run. Pulled out nice, ran down the lake.
Get about 7 mins down the lake, and it bogs down to next to nothing... limping... sounds like firing on one cylinder, yet, if I pull a spark plug lead, neither one of them kills it... (both obviously does)
Fussing and fiddling, and I might get it to run full tilt... briefly.
But generally once I get it to run (which isn't super easy) I have to limp back to the dock.
Running tied to the dock, I can warm it up, and run, and reproduce the problem.
And, the onset of the problem... is rather quick. It feels like electrical cut out, deliberate almost.
So, the web hit here on the forum, that suggested oil pressure cut out switch replacement. (the one that has a wire running to the CDI, and the light on the front)
There is no light, ever... but maybe it's dead. (tell me if that is worth looking into)
Marina up the road 30 mins had a Yamaha replacement oil pressure sender, so I have now also replaced that.
Same issue... at about the same amount of run time.
Oil level is good. Fuel supply is good.
Squeeze ball doesn't affect anything.
It feels like a failing spark, yet, not.
While running back on limp, one of the times, I swear it felt like it overheated and siezed... yet water coming out is a nice temp (just slightly warmer than lake temp)... and after checking everything, I was able to start it and run it again.
Open to other things to check next... again, when it runs, it runs perfectly.
As others have described in the past.
Thanks guys!
Am close to the motor for a few days here, hopeful we can find something obvious or simple to check?
Andy
I got to this forum via Google, with hits on similar challenges with the same motor, but none of the posted solutions so far, seem to have cured it. :-(
So, here we go... as requested, fresh posting.
1985 Yamaha F9.9SK 4 stroke
I don't have a lot of history on it, but in efforts to repair and get rolling again, here's what we have done.
There was no spark, so I used a voltage adapter and DVM, to diagnose "bad CDI". Managed to get a used CDI, matched up all the wires, and we have spark and life!
Carb got well cleaned out before that, and jets are clear.
Took some priming, and had to push some oil out of the exhaust (probably was stored improperly) and got it fired up and running.
Good stream of water from the one jet. (is the second jet supposed to be squirting? or is it some sort of overflow?)
Got it on the boat, and went for a run. Pulled out nice, ran down the lake.
Get about 7 mins down the lake, and it bogs down to next to nothing... limping... sounds like firing on one cylinder, yet, if I pull a spark plug lead, neither one of them kills it... (both obviously does)
Fussing and fiddling, and I might get it to run full tilt... briefly.
But generally once I get it to run (which isn't super easy) I have to limp back to the dock.
Running tied to the dock, I can warm it up, and run, and reproduce the problem.
And, the onset of the problem... is rather quick. It feels like electrical cut out, deliberate almost.
So, the web hit here on the forum, that suggested oil pressure cut out switch replacement. (the one that has a wire running to the CDI, and the light on the front)
There is no light, ever... but maybe it's dead. (tell me if that is worth looking into)
Marina up the road 30 mins had a Yamaha replacement oil pressure sender, so I have now also replaced that.
Same issue... at about the same amount of run time.
Oil level is good. Fuel supply is good.
Squeeze ball doesn't affect anything.
It feels like a failing spark, yet, not.
While running back on limp, one of the times, I swear it felt like it overheated and siezed... yet water coming out is a nice temp (just slightly warmer than lake temp)... and after checking everything, I was able to start it and run it again.
Open to other things to check next... again, when it runs, it runs perfectly.
As others have described in the past.
Thanks guys!
Am close to the motor for a few days here, hopeful we can find something obvious or simple to check?
Andy