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RonM
09-19-2005, 01:07 PM
Iím having a problem with my 1987 15hp Evinrude. It seems top have a flat spot while accelerating, if I get past the flat spot without stalling it runs great. I can idle, troll and run at higher RPMsí without a problem, itís only when I have to run just above an idle like when you have to go through the 5 mph area. Sometimes itís hard to get past the flat spot but eventually I can get the RPMís up. I checked the in-line squeeze ball on the fuel line and it seems to still be okay. If it stalls it will restart first pull. Thinking carb or fuel pump but leaning towards the carb. Does anyone have any ideals.

ThanksÖ

Ron

drstressor
09-19-2005, 01:57 PM
95% of the time it's the carb when they do that. The float could be hanging up a bit or one of the high speed jets is partially blocked. Time for a rebuild kit.

RonM
09-19-2005, 02:07 PM
95% of the time it's the carb when they do that. The float could be hanging up a bit or one of the high speed jets is partially blocked. Time for a rebuild kit.

Thanks for the confirmation Doc. I used to do the old 4bbl Rochecter Quadrajets a long time ago, this can't harder than that.


Ron

dempsey
09-19-2005, 03:48 PM
Hi Ron ,I had a simular problem with my 15hp Evenrude. Mine would peter out at top end, sometimes I could feather the throttle and it would take off again and other times it would die.If it died it would start back up on the first pull.All I did was clean the fuel filter, the little metal mesh screen. It only had a couple of small pieces of stuff on it but that solved my problem!! It's the first thing to try it's cheap and you can do iy yourself.
Good luck

RonM
09-19-2005, 04:08 PM
Hi Ron ,I had a simular problem with my 15hp Evenrude. Mine would peter out at top end, sometimes I could feather the throttle and it would take off again and other times it would die.If it died it would start back up on the first pull.All I did was clean the fuel filter, the little metal mesh screen. It only had a couple of small pieces of stuff on it but that solved my problem!! It's the first thing to try it's cheap and you can do iy yourself.
Good luck

Thanks Dempsey, I cleaned the filter already. I even sprayed a little carb cleaner into the carb while running to try and clean it out. I didn't want to spray to much since there's no lubricant in the carb cleaner. Seemed to run okay for a few hours and started back up.

Ron

wetdog
09-19-2005, 04:10 PM
Run a can of Seafoam through a tank of gas , you could very well solve your problem ...good stuff! ;)

drstressor
09-19-2005, 04:23 PM
I'll second the Seafoam. Any older 2-stroke will benefit from a treatment. And it MIGHT even clean up the carb enough to solve your problem for a little while longer.

RonM
09-19-2005, 05:17 PM
Sea Foam, that would be great if it will do the job. I checked the Sea Foam website and the Napa Warehouse on Northgate is down the block from work. I called and they do carry the product.

Thanks...

RonM
09-20-2005, 11:51 AM
Picked up the Sea Foam. I'll put some into the tank and run it for a while then I'll take it out this weekend and run it some more. I'll let you know if it works.

drstressor
09-20-2005, 12:26 PM
This is close to the method I use to de-carbon and clean up the carb:

http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=36;t=000006

RonM
09-20-2005, 01:27 PM
Should be easy, thanks for the info Doc.

RonM
09-25-2005, 12:28 PM
I used the Sea Foam to flush the motor. didn't resolve the probelm but I did find what was causing the issue. There is a cam just under the flywheel that makes contact with a plastic roller connected to the throttle valve on the carb. The plastic roller shaft has a crack and will not push the throttle down as it should. Time for a trip to the outboard parts shop. Thanks for the help, at least I have my motor cleaned and flushed out now.