Logo
FULL SITE MENU

1965 40 hp Evinrude Lark VII Wiring Configuration & Motor Testing

well----Same parts used on 2 , 3 , 4 , 5.5 , 6 , 7.5 , 10 , 18 , 25 , 28 , 33 , 40 HP models from about 1950 to 1984.----I would be surprised if you local motor shop did not have the parts in stock.
 
Parts have been ordered and arrive tomorrow.
Pulled the flywheel this evening and examined the existing parts. A couple of problems were discovered. We adjusted the points which were barely opening and are now set to .020 in. as the crankshaft rotates into position. Also, the spark plug on the lower cylinder had no gap at all, which may have been a main culprit. Planning on purchasing new plugs, gapping them to 0.030 in. and reassembling to test the motor. If everything works smoothly and runs far better than "Day 1" it's my plan to use the existing parts. If it still runs rough, I will disassemble again and install all new. With one spark plug that had no gap and points nowhere close to 0.20, how likely do you think it is that that was causing most of my trouble? I'll of course update this after tomorrow's activities.

Photos of existing parts:
IMG_20210629_191923444_HDR.jpg IMG_20210629_191933230_HDR.jpg IMG_20210629_191940565_HDR.jpg IMG_20210629_191955663_HDR.jpg IMG_20210629_192007735_HDR.jpg
 
The oiler wick is missing.------The bracket for the wick is there under the one coil.------Keeps rubbing blocks for points lubricated.---What sparkplugs ( J4C ? ) were in there.----Clean points and test for spark.----Spark if good can jump a gap of 1/4" with ease.
 
Last edited:
Champion Spark plugs L4J equivalent as recommended by the Clymer manual.
I mentioned the J4C to the guy at Napa and he told me the reach on the J4C was 3/8" versus the other (L4J) was 1/2". Is one preferable to the other?

When I showed them the picture of the coil with the oiler wick bracket, they didn't know how to look such a thing up. Any suggestion on obtaining the oiler wick?
 
Last edited:
Nope----L series plugs are too long.----Just not right !!-----You just need to go to a boat shop with a grey haired chap.----These NAPA places are very experienced with boat stuff.-----The oiler wick comes in the package for new factory breaker points.
 
Points and plugs adjusted and boat is running like a dream. Sounds great, idles properly and starts with gusto. The oiler wick came in and I need to pull it back apart and install it, but it's nice to see the adjustments were so effective.

How about running lights wiring? Where do the leads from the running lights connect in the electrical system? Here's a wiring diagram and a picture of the electrical box, but I can't figure where I should connect them in the system.

Electrical_JunctionBox_20200812_183837.jpg
Electrical_Selectric_Merged.jpg
 
Outside connection. Right again. Thank you.

Here we go again with the motor. For 2 days it ran smooth and idled smoothly. We burned 2 tanks of 100% gas, 90-octane mixed 50:1. Today I took my wife and daughter out skiing like the day before. I noticed the motor ran a bit rougher and new sounds developed at idle and at speed. Here's another video with the current sounds at idle, accelerating and back to idle.

https://youtu.be/aNFrtDQFx8g

Pulled the flywheel 3 days prior. Gapped the points to 0.20 and replaced the spark plugs and gapped them to 0.30. Ran like a dream for 2 days. New sounds are developing as it runs roughly as you'll hear.

I have all of the new parts that I could install if you think that might be the issue: coils, points (w/oiler wicks), and condensers.
 
Last edited:
For anyone who has made it this far in this thread, the story ends well. Since my last post, I removed and replaced all of the electronics suggested by Racerone: coils, condensers, points and spark plugs. I even found the "grey haired chap," Fred, at our local Sportsfisherman's boat shop who agreed the L4J were the wrong plugs. The boat fired right up but still had chugging issues and idling problems.

I moved on to the carburetor and obtained a carb tune-up kit and a new float from Fred. Having never worked on a carburetor I was nervous, but it went swimmingly well. Not wanting to leave anything to chance, I replaced the old metal Johnson fuel tank and the fuel line with the squeeze ball. When I tested it on land it fired right up. When we launched it at the boat ramp...thank you JESUS it ran like a dream.

On smooth water, FIREFLY, our 1958 15.5' Lyman Runabout powered by the 1965 Evinrude Lark VII 40 hp is topping out at 29.5 mph and the needle might even have touched 30 once or twice. With 2 adults and 3 teenagers last night, FIREFLY cruised comfortably at 24 mph out onto Lake Michigan. She's running so well and my kids and nieces are loving every minute of it, just like I did back in 1985. HUGE thanks to Racerone for all of your incredibly timely and accurate responses.

DSC_6193_cropped.jpg

Carburetor_6up.jpg
 
I have worked on many of them.----These are simple , reliable and rugged motors that do not have a $2000 ECU or other sensors.-----Easy to maintain by the average person.----Parts and used parts are everywhere.-----Brother had a 1965 model with standard shift.
 
Hi, i just finished reading your thread, I am so glad it worked out well in the end. I just purchased what I believe is a 1970 Evinrude 40 hp lark X, it was dark, late and I was too excited. I purchased it and brought it home without really inspecting as the seller was very convincing that it was working perfectly 2 years ago. Upon inspecting it I find out that its electric shift and it didnt come with controls (didnt even know there was such a thing as electric shiftso I assumed it was like my 15hp and had manual shift). The boat that I purchased had evinrude controls left over by the PO and the plugs look identical to the harness that came with the boat. Im hoping my engine restoration will end as well as yours but its now 3am and Im hoping to start my own thread. I just spent the last few hours going over the motor and thinking I had been fooled by the seller... Im hoping for a favorable outcome like yours, I was about to start looking for another motor but reading your thread has given me some hope that it may still run. Thanks for posting all your hard work!
 
Back
Top