1980 70 hp evinrude wont run over 4000 rpms and starting issues?

[ssgrant]

My 1980 70 hp evinrude runs fine until I get to around 4,000 rpm. after that it sounds real loud like a gear is slipping and wont go until I slow it down again. any ideas what the problem is?

also i have a starting issue. when I turned the key to start nothing at all happens. I took the cover off and tried to start with a string. after pulling a couple times it didnt start but when I tried the key again it did start. I turned it off and the same thing happened again. any ideas what this problem is?

Thanks for any advice!!!!

 

[Daviet]

Re: 1980 70 hp evinrude wont run over 4000 rpms and starting issues?

1st problem, have you checked the spark and compression on each cylinder? You could have a restriction in the high speed orifices, have you tried pumping the primer bulb to see if the engine would pick up?
2nd problem, have you checked the voltage to the starter solenoid when it would not start, does the starter solenoid click when you turn the key to start?

 

[ssgrant]

Re: 1980 70 hp evinrude wont run over 4000 rpms and starting issues?

Daviet,

I just got back this afternoon and havent done anything yet, but down load a service maual. I have little experience working on motors except for basic maintance but want to learn. That being said I'm thankful for your reply so I have some idea where to start and what to look for in the manual.
Another problem I forgot to add which happened first is the key choke also doesnt work. If I lift upon the choke linkage it will start. I dont know if this relates to the other problem or not

I can check the spark but how do you check compression?

There was no noise at all when I turned the key, I can check the voltage tomorrow, what should I be looking for?

Thanks again for your help!