1958 Lark 35 hp loud bang

[kfa4303]

Re: 1958 Lark 35 hp loud bang

Here are some great link that can help you rebuild the ignition and give that beautiful old motor and overall tune up. You should be able to get any routine parts you may need right here at iboats.

http://www.duckworksmagazine.com/04/s/columns/max/24/index.cfm

http://www.outboard-boat-motor-repa...on 3 HP 1952-1967 Ignition System Tune-up.htm

http://www.outboard-boat-motor-repa...hnson 5.5 HP 1954-1964 Carburetor Tune-UP.htm

http://www.marineengine.com/parts/v...ntage-evinrude-johnson/377518/37751800001.htm

 

[ceelonium]

Re: 1958 Lark 35 hp loud bang

I noticed that my gap adjustment screws are fairly loose. They have a lot of play in them. Is this normal?

 

[Chinewalker]

Re: 1958 Lark 35 hp loud bang

Yes, the offset screws are not not meant to be tight. The friction on the points center screw keeps the offset screw from moving more than is allowed within the oval hole.

 

[ceelonium]

Re: 1958 Lark 35 hp loud bang

so the gap between the points actually changes as the shaft turns?

 

[kfa4303]

Re: 1958 Lark 35 hp loud bang

yes. there is a oblong cam on the crank shaft that rubs against the rocker arms of the points such that as on arm rides the lobe on the cam, the points are opened to their maximum gap of .020" (set by using a feeler gauge), while simultaneously the other set of points is fully closed, allowing for alternate firing of the cylinders. You can think of them sort of like castanets. Here's a couple good links.

http://www.duckworksmagazine.com/03/r/columns/max/07/index.htm

http://www.outboard-boat-motor-repa...on 3 HP 1952-1967 Ignition System Tune-up.htm

 

[1946Zephyr]

Re: 1958 Lark 35 hp loud bang

What I would do, is pull the entire magplate off and clean it up. Totally go through it and clean and regap the points. The tips of those points look pretty dirty. The faces of the coil need to be lined up perfectly, with the bosses they are mounted on. I use a utility knife blade and hold the magplate up towards the light. to see that there is no light shining through anywhere on the coil face and machined boss. This here will get the coil adjustment about as perfect as it gets. Frank Robb sells coil mounting rings that make the job a lot easier and quicker, but the average boater doesn't have one of those.

I like the color scheme on that motor. That model year looks better in white.

 

[nwcove]

Re: 1958 Lark 35 hp loud bang

so the gap between the points actually changes as the shaft turns?

yes, and when the points open for each respective coil, thats when the plug fires.

i did notice in one of the pics, that the ground wire for one coil has been chaffing on the flywheel, also the green wires look as tho they could become an issue if you dont re-route them away from any moving parts.

 

[nwcove]

Re: 1958 Lark 35 hp loud bang



heres roughly how the wires should be routed/tucked away. notice that they are well back or under and away from anything that moves.

 

[ceelonium]

Re: 1958 Lark 35 hp loud bang

Thanks for all the great input and the links, which I will be studying thoroughly before getting my hands dirty. I have a manual for this motor, but the pics are very faded and lacking in detail - so the links are a much needed relief from eye squinting at an old faded manual.

I have ordered the Sierra Carb kit 18-7024 and will also get the points, etc cleaned up as good as I can.

biggest challenge will be tucking those wires neatly away.

@ 1946Zephyr: The color scheme is nice indeed, I wouldn't have it any other way. I do want to try to replace the round plastic emblems on the side - however - it looks like they are fastened to the cowl with rivets, which will become tricky I'm sure.

I get a lot of people stopping me whenever I have the boat out. She really is an attention grabber.

 

[kfa4303]

Re: 1958 Lark 35 hp loud bang

Here's a pic of what your magneto should look like when it's all done.

 

[ceelonium]

Re: 1958 Lark 35 hp loud bang

Ok so I have the carb taken apart - cleaned up with toothbrush, cotton swabs, toothpicks - and parts soaking in pb blaster.

One Concern I have is with the intake manifold. The housing which the carb bolts on to. I took a look inside and see more fire retardant. I can't believe this stuff got all the way in there.

Should I be worried that this stuff got into the cylinders? How exactly does the intake manifold work? I don't see an air filter per say. Is there not one on outboards?

Thanks

 

[nwcove]

Re: 1958 Lark 35 hp loud bang

no air filter on most ob's.....most just have a silencer on the carb(s), more or less a muffler to keep noise down. if you sprayed the engine with an extinguisher while it was running.....the chems definitely got into the workings of the engine!

 

[ceelonium]

Re: 1958 Lark 35 hp loud bang

best I can recall - Engine went "bang" as I was turning her over to get her started. I don't think she ever started though during that attempt. I had the cowl door open, and I am guessing as I was holding the choke and trying to start her (key-start ignition) the fumes mixed with some air and a spark ignited a pocket of volatile vapor. It was a pretty loud bang. Scared the bejivers out of me. Looking back though; I should have just thrown my shirt over the carb, instead of going all firefighter style on her.

The fact that these motors don't have much of an air filter, other than what's on the front of the carb, plus the silencer, I am surprised the same principle doesn't apply here as it does with car engines for example.

 

[Chinewalker]

Re: 1958 Lark 35 hp loud bang

They went hot and cold on silencers. Some motors have them, some don't. If designed properly, a silencer can also have a performance benefit as it can "bounce" the standing wave that is produced in front of the carb mouth while running. Bouncing it back into the carb can give a minute boost to the charge. As for a filtration system, why would you need one? Not much dust kicked up over the water...

 

[ceelonium]

Re: 1958 Lark 35 hp loud bang

Ok so I rebuilt the carb, changed the spark plugs and used fresh gas/oil, slapped everything back together; put her in a barrell - low and behold she started up on the first try. I am astounded at that. Really!!

no having to fiddle with the carb adjustments (although I will later on the lake)... no unsuccessful first-attempts, etc etc

nope she just started right on up. Gears seem to be fine. Water is coming out of the little pee hole as it did before.

Of course it wasn't all just a simple stroll down 58' Evinrude lane, that is, without its hiccups; such as accidentally stripping out the lower spark plug threads and having to retap. The top ones were retapped by a previous owner: go figure.

Overall I did nothing to the magneto whatsoever, except tighten and very slightly readjust a component here or there. Everything sitting on that plate looked (as I mentioned very early on) brand-spanking new, so no need to replace anything - and cudos to the previous owner.



My first car ever was a 64 Chevy II (Nova) with a straight six in it. One of the simplest engines to work and learn on. I hope in coming years I will be able to say the same about the Evinrude outboard.