Guests - If You want access to member only forums on FM. You will gain access only when you Sign-in or Sign-Up on Fishing Minnesota.

It's easy - LOOK UPPER right menu.

Sign in to follow this  
Followers 0
EyeNCrappieGuy

1980's 40 HP Evinrude Troubles

7 posts in this topic

Hey Gentlemen.

I have an older 40 HP Evinrude electric start tiller. It typically starts, trolls, and idles fine. My trouble comes when trying to run it wide open. It will sometimes only go about 1/2 throttle, even though you turn it wide open. After the throttle is half way open, and you continue turning, there is no noticeable difference in sound or speed. When happening, it won't even plane out. Even more mystifying is that one day it will run fine all day, and the next it will never make plane. Still other days it's mixed all day. This has been going on for a year or so and I'm ready to take care of it this spring!!

Does anybody have any ideas on what would cause and/or fix this type of a "high speed" trouble?

All I've done so far is replace the plugs and run some Amsoil fuel system cleaner through it.

Thanks in advance!

Share this post


Link to post
Share on other sites

Remove both of the spark plugs and describe what the tips look like. Is one clean and the other dirty? If one is clean that unit cylinder will be the problem. Without further information it could be a fuel pump, dirty carbs a cylinder with no fire, a blown head gasket or a bad cylinder. Another thing you can try is choking the motor at WOT and see if that kills the motor or improves the performance. If it improves the performance you have a fuel related issue. The best thing to do is do a spark test and a compression test. These tests will tend to narrow down what is going wrong. Most cases it is a fuel problem like a dirty carb or a blown fuel pump diaphram.

Share this post


Link to post
Share on other sites

OK, thanks!

One thing I forgot to mention, I don't have a choke (that I know of) but it does have an electric primer bulb....when it's acting up and I'm at WOT and keep pressing it repeatedly, I can reach "top speed" but typically as I stop jamming the primer, it coasts back to a fast troll.

So taking what you said, that would be pointing to some type of fuel system issue then. At least this is a starting point!

Share this post


Link to post
Share on other sites

I am a force chrysler guy and will leave it to someone who knows evinrudes. My answer is pretty generic and I agree you have a problem with the fuel system which is good. Carb rebuilds, fuel pumps and such are pennies on the dollars compared to replacing electrical components. I am sure someone here will be able to help you that has evinrude experience. I would get a service manual if it were me. I personally like Clymor and factory manuals. Check out a larger public library and you can probably sign one out for three weeks. Good luck

Share this post


Link to post
Share on other sites

Eurolarva found the problem. It's your carburators, they need rebuilt.

Your primer injects a squirt of gas past the carb to help cold starts, when you do this at WOT it means your jets are not allowing enough gas to go through or your floats won't allow much gas to come in.

Get 2 carb kits, follow instructions (if they have it, otherwise a good manual is a must), and it will solve your problem.

Bad jetting can also cause lean mixture on 1 or 2 cyls which can develop serious problem,s you have to fix this.

Share this post


Link to post
Share on other sites

Thanks for the help on this one guys! Really appreciate it.

Share this post


Link to post
Share on other sites

I've owned several OMC motors, including an '88 40 Johnson tiller, also a 60hp and that black "primer bulb" is actually an electric choke. Press and hold it for choke.

If you hit the choke and get higher RPMs I'm thinking a fuel delivery issue (fuel pump, hoses, etc) or dirty carbs, main jet particularily. Like other's have said...

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.
Sign in to follow this  
Followers 0



  • Posts

    • Rick G
      Thanks for the update , Don.  Some of the smaller bodies of water in our area capped over last night. I'm hoping there will be walkable ice somewhere by the weekend
    • Rick
      Hunting or fishing license holders can order discounted tickets to the Sunday, Dec. 11, Minnesota Wild hockey game vs. the St. Louis Blues, as the Wild and the Department of Natural Resources team up for this special ticket offer.   A limited number of tickets are available and will be reserved on a first-come, first-served basis. Ticket prices vary and the offer is available only through advance online purchase on the Wild webpage, to hunting or fishing license holders for 2016 or 2017. The discount is not available at the Xcel Energy Center box office. Buy fishing and hunting licenses at DNR license agents, online with a mobile or desktop device on the buy a license page, or by phone at 888-665-4236. Mobile buyers receive a text or email that serves as proof of a valid fish or game license to state conservation officers. Discuss below - to view set the hook here.
    • Rick
      The deadline for firearms wild turkey hunters to apply for early season spring hunting permits is Friday, Jan. 27, according to the Minnesota Department of Natural Resources. The spring season, which runs from Wednesday, April 12, to Wednesday, May 31, is divided into six time periods. Only people age 18 and older who want to hunt using a firearm during the first two time periods (A or B) need to apply for a spring turkey permit. Permits for the remaining time periods (C-F) can be purchased over-the-counter. Archery and youth turkey hunters can hunt the entire season without applying for the lottery. Permits for the last three time periods and youth licenses are sold starting March 1. Surplus adult licenses from the first two time periods, if available, are sold starting around mid-March. People applying for permit area 511, the Carlos Avery State Wildlife Management Area, are advised that the sanctuary portion of the WMA will be closed to turkey hunting except for the special hunt for hunters with disabilities. For turkey hunting, a person may only use shotguns 20 gauge or larger, including muzzleloading shotguns. Only fine shot size No. 4 and smaller diameter may be used, and red dot scopes and range finders are legal. Visit the turkey hunting page  for more information about turkey hunting. Discuss below - to view set the hook here.
    • Neighbor_guy
      We did some roadside scouting in the Chippewa national forest on Sunday. Put on a pile of miles driving the forest roads with the fresh dusting of snow and never cut a track. Kinda disappointing, but my daughter wasn't really up for it.    Season is still young. 
    • Neighbor_guy
      well we found a small amount of ice. But it was only about 1"thick. And only reached out a couple hundred yards at best. The swans were loving all the open water that's for sure.    Those that did come up to the GTG had a good time despite the lack of ice. Mostly hunting for grouse and rabbits. Plenty of both seen, but the shooting was less than stellar.