1985 90 hp johnson runs then powers down

[Arlhoy]

I have a 90 hp 1985 johnson and was running about 3000 rpms with good water flow out the indicator. After 10 minutes of this the motor lost power slowly and died. The engine acted like it was vapor locked for about 5 minutes. After that it started but runs as if it is missing on 1 cylinder. Know knocking. If anyone knows anything i would appreciate it.

 

[crazyray]

Re: 1985 90 hp johnson runs then powers down

you should run a compression test first see if you have a have a dead cylinder or such.....get back with your results of this will try and help ya along