1986 Evinrude 150 hp Throttle questions

[3899]

Hello, working on my winter projects, got me to checking the throttles and linkage. I'm wondering as I'm watching the operation of the carbs, when I'm at full throttle, should the carbs be completely open? The arms are going as far as they're supposed to, but the three throttle plates are only going to 3/4 open. I can manually get them to go 100%, and can see how to adjust it to make it happen, but is this the standard amount? The boat is an 18' Ranger, and the most I could muster out of her last year was 48 MPH. Although it ran great, I just thought maybe it should be more. I am replacing all the hard as a rock fuel hoses, and cleaned a very dirty fuel filter, so I'm confident it will start and run good. Just want it to give me all it can. I didn't pay any attention to wide open rpm's, so not sure if I was topped out or not. Also one other question, the rocker arms that the linkages attatch to, don't return fully back to the base idle stop points, so it wants to idle a little fast after putting back into neutral. I can pull it back and it stays on the stops. Is there supposed to be more spring tension on the arms to return them to the adjustment stops?
Thanks for any input.
Jeff

 

[boobie]

Re: 1986 Evinrude 150 hp Throttle questions

You should get an OEM Factory Service as all the sync & link procedures are in them. Also a lot of other good info if you're going to do a lot of work yourself. Your throttle may not be returning to idle due to a sticky timer base.

 

[3899]

Re: 1986 Evinrude 150 hp Throttle questions

Alright. Thanks I'll check that. Don't think I need to adjust on it too much...just was curious about the amount the throttles were supposed to open. Thanks again!

 

[boobie]

Re: 1986 Evinrude 150 hp Throttle questions

If sync & linked properly the throttle plates should be pararell with the bore of the carb or flat at WOT.

 

[emdsapmgr]

Re: 1986 Evinrude 150 hp Throttle questions

Something's not sync'd properly if the carbs only open 3/4. It's a simple adjustment issue. If you plan to perform the sync and link procedure on this engine, you may want acquire an original factory manual to use as reference. Check out this website: outboardbooks.com. With age, the original factory grease under the timer base can dry out, causing it's normal movement to be stiff. You may want to pull the timer base off and clean the old grease off the powerhead and the timer base. Re-lube with some white lithium grease-it's really slippery in all temperatures. Will really make a difference.