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oakcenter

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I recently inherited my Dad's 100HP Evinrude 1966 outboard. He purchased this new and always took great care of it. What type/brand of 2 stroke oil should I use?
Thank You
 
A motor just like that towed me around the lake in the late 60's early 70's-----Run with a good quality TCW-3 oil at 50:1 mix.-An excellent and rugged motor that you can maintain yourself.-----Just make sure no water gets into that lower unit !
 
Thanks for the quick reply. There's a lot of different brands out there. Is synthetic ok? What brand would you use if it were your engine? Thanks Again!
 
Any recognized brand of TCW-3 oil ----Esso / Shell / Johnson / BRP / Evinrude / Mercury.-----Even expensive oil is cheap compared to having to buy a new motor.
 
Engine was bogging now at middle to full throttle. Pulled the plugs and they are oil fouled. I'm using Autolite 353 plugs. Any suggestions on what to do or a better spark plug to use. Thanks
 
Fouled plugs are usually caused by something.-----Is the thermostat / vernatherm installed and working properly ??
 
I took the thermostat housing cover off and found that there's no vernatherm, valve, or spring. See attached picture. Why would this be removed? 20150901_100005.jpg
 
People take these things out because they do not know / understand how things work !!!!----And they will listen to the neighbor and not a mechanic !!!
 
oakcenter said:
Engine was bogging now at middle to full throttle. Pulled the plugs and they are oil fouled. I'm using Autolite 353 plugs. Any suggestions on what to do or a better spark plug to use. Thanks
Click to expand...
Recommended plugs are Champion J4C .... but Autolite353 are one of the listed equivalents

Refit a Vernatherm .... dunno why people not heard of them ??????

They get taken out because people believe they are only necessary in cold climates.
 
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Like anything else, an outboard has to run at the proper temp to be efficient and reliable. The thermostat/vernatherm is critical to maintain that operating temp. I would consider a J6C or Autolite 303 if you run at slower speeds often. Oils are better these days, I have an identical motor and run Amsoil pre mix 100:1 (fully synthetic), but mixed at 2 oz per gallon of non oxy 91 octane fuel (64:1). Check your spark action and it should easily arc 3/8" on this baby if all is correct. Thats just my advice, others may have something else for you......I have been an Amsoil user for 36 years and with 2 resorts in remote Ontario.......I have yet to experience a major powerhead failure with the "snakeoil", but really.....its made from old rotten animals......go ahead if you don't believe me, just smell it. In truth, petroleum based oils are nothing but rotten plants and animals too.......fossil fuel?????
 
With the new vernatherm installed it smokes a lot more than it use to. Before there wasn't much smoke. There is also more oily water coming out of these two holes when removed from the water(see attached pics) The only thing I've done differently is used NGK plugs instead of Autolites. Oil Leak.jpgOil Leak 2.jpg
 
I took the thermostat cover off to show the two springs. One on the left is the check valve spring and the one on the right is the vernatherm spring. The vernatherm spring is very rigid. Is it suppose to be very stiff? I've also included a link to a video of my engine running so you can see the smoke I'm taking about.

Thermostat Housing.jpg

 
It's an 80hp. The engine cover had been stripped so there was nothing identifying the hp. I found the model number and was able to identify it. My Dad always said it was a 100. Not sure why he stripped the cover, maybe to restore. I hadn't seen it for 30 years so was just taking his word. Any thoughts on my smoking issue in regards to putting in a new vernatherm?
 
In the first place your need to understand what you have there. A tough and reliable old motor, state of the art when it was new. Having said that, you must understand that was then and now is now. Back then, those motors were expected to be very inefficient, smoke, and make a mess. That's just the way it was. So don't be alarmed by the smoke and drainage. What you can do is make sure it is operating properly, and adjusted properly. Getting the thermostat working was part of that process. Then use it and enjoy it.

Hmmmmm, I'm wondering, are you running it on a boat on the lake, or are you running it in the yard on muffs or tub? If you are, well there is half your problem. It was designed to run on a boat on the lake.

If I am not mistaken, that one has a automotive-type distributor, right? As simple and reliable as any car of the day. But fouled plugs were common also, especially if not running and adjusted properly. Back to the basics, get it out on the lake (yes, with your new thermostat), and run the daylights out of it to burn off the accumulated oil and crud caused by running too cold. When done, you probably will find it smokes less, and is cleaner.

To answer your question, yes the strong spring goes over the vernatherm valve.

EDIT: Sorry, I had not yet watched your video when I wrote all that. At least my suspicions were correct, you are running it in a container---a pretty nice one, I might add. I'm not so sure that is all smoke. Sure looks like a lot of steam mixed in. Steam is normal, how much is too much, hard to say. The thermostat does force it to come up to 140 degrees before it opens, then it mixes with hot exhaust gasses. What is the outside air temp? Cold and wintery? You might want to actually check the powerhead temperatures.
 
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Thanks for all the good info. It was about 45 degrees when I was running it. I checked the powerhead temps with an infrared thermometer where the temperature switch is and the same spot on the other 3 cylinders. New vernatherm is installed. The temps would range from 125-135. Is it not getting hot enough? Currently I'm using NGK B7S plugs, but would like to try the Champion plugs OMC specifies. In a previous post timeguy suggested using Champion J6C. My shop manual lists J4J which my parts store said is J4C today. What would be the advantage of J4C or J6C?
 
Did you run with motor in a tub or on a hose with water supplied at PRESSURE ??-------Way back , when most Johnson / Evinrude shops just had to have J4J and J6J on hand the rule was --------J4J for motors with themostats and J6J for motors without thermostats.------As for the reason , A J6J has a longer path for heat to travel , so the plug materials inside the chamber stay warmer / hotter.
 
Personally, I think your motor is just fine. Take it for a ride and see. As for the spark plugs, understand that the plugs have to operate hot enough to prevent fouling at slow speeds and cool enough to prevent pre-ignition and catastrophic engine damage at wide open throttle. That's asking a lot. But the mfr specified plugs that come as close as possible to meeting the requirements. J4J was a special two-stroke plug, no longer made and replaced by J4C. Same heat range. A J6C is one step hotter. OK, but don't go any hotter than that. "hot" and "cold" refer to how hot the plug tip gets under combustion, not how hot the engine gets.
 
Sounds like you have a miss to me did you do a cylinder drop test to see if it was firing on all cylinders? While the engine is running at an idle pull a plug wire and quickly put it back on. The engine should respond the same on all cylinders. You normally notice the difference when you put the wire back on. Use a good pair of insulated pliers so you dont get zapped. I prefer the hand test for checking temps, just put your hand on the head and count slow to six. The heads should get hot enough you want to pull your hand away but dont have to. Yea that looks like steam to me as it quickly dissipates smoke would leave a cloud. I wouldnt hurt to do a decarb I imagine the pistons and rings are all crudded up from running too cold. Shine a light in the spark plug holes if you see alot of carbon on the top of the pistons do compression test. Then do a decarb and then check the compression again.
 
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