1970 Evinrude 9.5 problem

[hippovet]

My 1970 Evinrude 9.5 "catches" or hesitates - won't run smooth. I bought it recently and it never has run properly. It only seems to keep running with the choke closed and occasionally the rpms increase for no reason. I've cleaned and rebuilt the carburetor, installed new points and condensors, new plugs, new low speed needle, everything I can think of. Points set at .20 and plugs at .30. The coils look new. The spark seems good. The previous owner installed a new fuel pump. Compression on both cylinders is 65. Any ideas? Thanks.

 

[racerone]

Did you remove the highspeed jet from the carburetor bowl for inspection / cleaning.--------It is about 5/8" long with 1/4-20 thread on it??----What are the compression numbers ?-Perhaps use a timing light on it to determine if you have a spark issue or if it is something else.------The plug wires are known to short out where they take a 90 degree bend exiting the magplate.

 

[dkonrai]

check the reeds. my buddies motor had pitted reeds and caused the same symptons. worth a shot

 

[hippovet]

Thanks to all of you for your ideas. I haven't had time to work on the engine since I did the post. When I do, I'll let you know how it goes.

 

[scruffy63]

Check the rubber O-Ring on the slow speed adjustment. They need a tight seal to prevent air leaking and causes a popping at idle.

 

[andrew04]

Also verify timing of ignition and throttle, its played out in the manual, and it matters. Is fuel pump in good shape? Fuel line and tank?