1990 Evinrude 20hp tune up need help

[Spcamno]

Just accuired an used 1990 Evinrude 20hp was managed to start it yesterday however its back fire a little and knowing the motor has been sitting for more than 4 years before and will clean the carb regardless.

However, I can't find any information on what ignition system this motor has,is there any point to replace?

Also,the fuel fitting leaks a little will this cause the motor to back fire?

Is there a choke on this motor?

By reading the secret file you need to prime it a couple of times and pull the knob out half to full out but it won't stay its position when you pull it out (it will slowly retract) is this normal?
The lower unit shaft seal requires replacing any special tools require?

Thank you very much in advance!

Cheers

 

[bktheking]

Re: 1990 Evinrude 20hp tune up need help

However, I can't find any information on what ignition system this motor has,is there any point to replace?

No, it's pointless ignition, if you have spark on both cylinders then it should be working.

Also,the fuel fitting leaks a little will this cause the motor to back fire? - It shouldn't leak, rebuild the carb , may be causing it to backfire

Is there a choke on this motor? Don't see one in the diagram, shows a primer instead



Don't know about the primer function, sorry

By reading the secret file you need to prime it a couple of times and pull the knob out half to full out but it won't stay its position when you pull it out (it will slowly retract) is this normal?
The lower unit shaft seal requires replacing any special tools require?

Thank you very much in advance!

Cheers

see bolded above

 

[Spcamno]

Re: 1990 Evinrude 20hp tune up need help

see bolded above

Thank bktheking for your post!

Its nice to see someone local (I'm in the GTA).

Cheers & have a good one!

 

[tashasdaddy]

Re: 1990 Evinrude 20hp tune up need help

your motor has a manual primer, rather than a choke. you pump the knob a couple of times, this pumps fuel directly into the intake.

 

[Spcamno]

Re: 1990 Evinrude 20hp tune up need help

Thanks tashasdaddy for your post.

Any idea what would cause the slight back fire?

I know its been sitting for several years before should I rebuild the carb as bktheking first?

Thx

 

[bktheking]

Re: 1990 Evinrude 20hp tune up need help

Thank bktheking for your post!

Its nice to see someone local (I'm in the GTA).

Cheers & have a good one!

Dirty carb can cause a backfire for sure.


Semi local, i'll be heading your way in January to pick up a Merc kh7 in Oakville, yes you read it right, Merc kh7.

 

[Spcamno]

Re: 1990 Evinrude 20hp tune up need help

Dirty carb can cause a backfire for sure.


Semi local, i'll be heading your way in January to pick up a Merc kh7 in Oakville, yes you read it right, Merc kh7.

WoW,you sure like to tinker with antique motor(LOL).

I have an older Johnson 3hp (50s?) in fair condition may be you can give some pointers to restore it.

Thank for your tips on the carb I guess I will play with it in the spring coz its too damn cold to work on it in my unheated garage!

 

[bktheking]

Re: 1990 Evinrude 20hp tune up need help

Agreed, mine are all asleep.

Sure, I've got a 50's Viking 3hp to fix up , same sorta deal