18hp Evinrude loss of power

[rude66]

I have a 1966 18hp Evinrude 2cyl (18602). I am curious if anyone knows of any solutions to try for my problem. The motor usually starts great but thats where the greatness stops. I am having alot of knocking and sputtering at low RPM. I have adjusted the lean/rich setting on the front of the motor but it seems like it dosent do anything. Also, when I give it some gas i have to pull the choke out to keep it from dying. Once the choke is out it runs alot better and I can get to where I need to go...just not in a hurry because when i give it full throttle it seems like it is throttling back on me. This gets worse as the motor gets warmed up. I have changed the plugs and the water pump is newer, I dont think overheating is the problem. Does it sound like a Carb rebuild is in order or is there some kind of adjustment on the motor that I dont know about? Or could my problem be unrelated to fuel?<br /><br />Thanks

 

[alcan]

Re: 18hp Evinrude loss of power

Hi Rude<br />When was the last time you gave it a full tune-up service. Sounds like it's time now. The first thing to do is get a repair manual for your motor. Then test for compression. If good,clean,adjust or replace points. Remove,clean carb and inspect fuel system. Sounds to me like you have crud in your carb. Was the vent on the tank open?

 

[rude66]

Re: 18hp Evinrude loss of power

I bought it 3 years ago and never have serviced it. Other then plug change, and oil. I would agree that it is about time. Im wondering on how easy it would be finding the parts and doing the service myself. The vent is open on the tank and the fuel hose is going the right direction. Also does anyone know where I can get the service manuals less expensive then from Evinrude. They want 100$ 1/4 the price of the motor.

 

[Chinewalker]

Re: 18hp Evinrude loss of power

Hi '66 Rude,<br /> As far as service parts - they are easily (and most of the time cheaply!) had at an OMC dealer or even NAPA. Points, coils, condensers, carb kits, fuel pumps, water pumps, all that stuff is readily available.<br /> For a manual, NAPA carries the SELOC line of manuals - decent aftermarket manuals. You'd want part #SE-67 and it'll run you under $40.00. Original OMC manuals turn up on eBay all the time. Your motor is quite similar to other 18hp models from 1960 to 1968, both Johnson and Evinrude, so that should broaden your search scope.<br /> I agree with Alcan - carb sounds junked up... It's a good, strong motor and certainly worth putting some time and money into...<br />- Scott

 

[alcan]

Re: 18hp Evinrude loss of power

Hi Rude<br />If the price of a manual seems to high at first, Try you public library. Most will have somthing. Once you use theirs you'll be buying your own. Well worth the money.