still need help 1961 40hp lark III Evirude

[john69lemans]

I am having problems with the motor not giong full power it runs well but will not open up on the water. I am also having problems with it keeping in time. twice I broke the key that hold the flywheel on. I thought it was the choke I have disconnected it . I have replaced the points and coils and rebuilt the carburator. Could it be the spark advance? If so how do I check it ? What is the over speed switch and the safty switch? Could this cause my problems? or any other sugestions! please help John

 

[tashasdaddy]

Re: still need help 1961 40hp lark III Evirude

did you replace the woodruff key with a original equipment key, and torque the flywheel to the recommended torque?

 

[F_R]

Re: still need help 1961 40hp lark III Evirude

The spark advance and timing is fixed and is not adjustable.

The vacuum cut-out switch prevents the motor from "running away" or revving out of control in neutral. The safety switch serves two purposes. One, it limits the operation of the vacuum cut-out switch to slow throttle settings, and two, it prevents operation of the electric starter at higher than slow throttle settings.

The flywheel and crankshaft tapers MUST be clean and dry before installing the flywheel. The nut MUST be tightened to 100-105 ft/lbs, using a torque wrench. No more and no less. 100-105 ft/lbs. You must use the correct key. If you don't follow these instructions, the key will shear and it may damage the flywheel and crankshaft beyond repair. Maybe yours already has. "Stuff" happens when you don't go by the book and use the right tools.

 

[john69lemans]

Re: still need help 1961 40hp lark III Evirude

thank you. How do I check to see if it is broken? I will go by the book and put back together I may not of torched it right. Does anyone have any clue why the motor will not go to full power? When i shake the shifter lever it acts like it wants to open up but dont. I have tryed to manualy shift but it does not help. Mabee a wire? any help would be great John

 

[tashasdaddy]

Re: still need help 1961 40hp lark III Evirude

you did not answer my question? if you don't answer we don't have enough info to help you. there could be a lot of reason, that's why we ask. to narrow it down. called trouble shooting.

 

[F_R]

Re: still need help 1961 40hp lark III Evirude

Aside from the flywheel question, your motor probably won't go full speed because it is not running on both cylinders. There are many possible reasons ranging from a bad spark plug wire to a blown piston. That is why a troubleshooting procedure is important, which starts with checking for spark (must jump a 1/4" gap) and a compression test.

 

[Evinrude Boater]

Re: still need help 1961 40hp lark III Evirude

thank you. How do I check to see if it is broken? I will go by the book and put back together I may not of torched it right. Does anyone have any clue why the motor will not go to full power? When i shake the shifter lever it acts like it wants to open up but dont. I have tryed to manualy shift but it does not help. Mabee a wire? any help would be great John

Slow down Johnnie. Take the flywheel off, the key will either be in one piece on the crankshaft or in two pieces with half in the crankshaft and the other half in the flywheel. If you've broken two already you should be pro at taking the flywheel off. Not so good at reassembly.
You need a 1/2" drive torque wrench to get the nut tight enough with all the arm that you have.
Replacing components to see if it works is what car dealers do. We troubleshoot to determine the problem.
Shaking the shift lever just doesn't make sense. You push the throttle lever down to make it go faster. At what point does the motor not go any faster? Half throttle? Three quarters? It could be as simple as dirt in the high speed jet restricting the flow of gas. What do the spark plugs look like? What fuel mix ratio are you using? What are the compression readings? When was the water pump last serviced?

 

[Willyclay]

Re: still need help 1961 40hp lark III Evirude

If this is a remote control motor, any chance the shift and throttle cables have been reversed to give the symptoms described? The flywheel key issue is something else. Good luck!

 

[john69lemans]

Re: still need help 1961 40hp lark III Evirude

I used the right key but did not torque it correct I am having problems finding another key any help or part number would be great. Or does any one know the size I can get them from a store here but they go by size.
The cylinders both have spark I will try and get a compression test done. I am running 50-1 fuel I rebuilt the carburator but i got some dirt if the filter at the fuil pump maybe it got some to the jet I will check. I have not done any thing to the watter pump but the water sems to be working wright.

 

[tashasdaddy]

Re: still need help 1961 40hp lark III Evirude

the key is a dealer item. hardware store will not hold up. as it is not hardened enough. you should be running 24:1 fuel/oil mix, not 50:1.

 

[Evinrude Boater]

Re: still need help 1961 40hp lark III Evirude

I have not done any thing to the watter pump but the water sems to be working wright.

I was just thinking that maybe the motor is overheating enough that the pistons are binding. The fuel ratio should make it run any different, just less lubrication and more wear. They changed to 50:1 in 1964.
If you've got good compression and spark then fuel is your next item to confirm.

 

[freddyray21]

Re: still need help 1961 40hp lark III Evirude

if you are shaking the shift lever and it wants to run a bit faster then my guess is the lock out on the gear shift is not adjusted right. At the top of the gear shift mechanism is a lock out that will keep the spark advance mechanism and throttle from moving too far forward in neutral or reverse. In forward it should flip out of the way so the throttle will open all the way.

 

[john69lemans]

Re: still need help 1961 40hp lark III Evirude

I took off the fly wheel again. I looked closer the spark plug wires has some scuf marks. I dont know if this could be the problem I ordered them today and a new key. it will be a few days befor I will know if that was the problem. How do I check to see if the spark advance is working right? Some-one else said they thought it was the problem?

 

[Evinrude Boater]

Re: still need help 1961 40hp lark III Evirude

How do I check to see if the spark advance is working right? Some-one else said they thought it was the problem?

When you get your manual go to the section that explains Link & Sync and go through that process. It's a bit much to explain here without photos.

 

[byacey]

Re: still need help 1961 40hp lark III Evirude

Is your switch located in the remote control housing? If so, any chance one of the magneto wires going to the ignition switch might be shorting against the shift/throttle cables?

First thing is to check for proper spark on both cylinders as previously mentioned. If it's a healthy spark on both cylinders the problem is either skinned / leaky wires from the magnetos or a wobbly armature plate disabling one of the cylinders as the timing is advanced.