1971 60 hp evinrude high speed problem

Spent too much at dealer, still no good. When accelerating it goes to about half throttle then stays at that speed. It idles well. Motor has been sitting for about 5 yrs and now wanting to get back into boating. Should I try again to have it fixed or scrap it and look for another motor?

Re: 1971 60 hp evinrude high speed problem

It probably is running on only two of the three cylinders. Continuing to run it that way can cause serious damage if the fault is one clogged carburetor. (No fuel = no oil to that cylinder).

It can also be other problems such as no/low compression on that cylinder, or ignition problems...not unusual on that motor.

As you can see, it is impossible to trouble shoot it from a distance.

Re: 1971 60 hp evinrude high speed problem

Use an inductive timing light to look for lack of spark or a miss in one of your cylinders. If that indicates that all three cylinders are firing, I would suspect junk fouling a high speed orifice in one of the carbs. To determine if that is true, try removing the front cover from the air silencer and then run the motor. You may be able to actually see the lack of spray, or intermittant spray, into the throat of the offending carb.

If you can not run the engine in a barrel, don't do these tests on a hose. You will need to advance the throttle a bit and need some resistence on the prop to prevent "overreving." I usually do them while underway with some help from someone else to drive the boat. Once caution, however, is to be careful of running an engine that is not getting sufficient fuel to a cylinder, as that lack of fuel also means a lack of lubrication.

Given the length of time that your motor has not been run, my guess is that it is in need of a carburetor rebuild, which should deal with any fouling of high and low speed jets/orifices.