1972 Evinrude Lark 50 - Issues!

[oldnnew]

Hi, I have a 1988 17' Sea Raider with a 1972 Evinrude Lark 50 (50273c) that I am having a few issues with. Recent work I have done to the motor is rebuilt both carbs and fuel pump, new fuel lines, and new spark plugs. The motor starts fairly good. However, when I go to forward gear, it doesn't want to stay running at idle. If I blip the throttle it will get going and I can idle down *somewhat*, but eventually will just die off and stall. Midrange also appears to have a slight misfiring, but top end is generally smooth running, however, I can only go about 3/4 throttle. If I take it full throttle, it hesitates and slows down. No backfiring or anything, just loses a little RPM. I have also noticed that when I start it cold, 50% of the time it will run on one cylinder, but then after running a bit, the cylinder will come back to life. I checked compression, 160psi in each cylinder. I have ordered a service manual for it and I think the best place to start is to put everything back to factory spec settings (seems like all sorts of adjustments on this thing!). In addition to going to all factory settings, maybe a "link and sync" and decarbonation is in order. Maybe that will help. I was just wondering if anyone else had any similar experiences with this dinosaur that could lend some advice... Thanks!

 

[F_R]

Re: 1972 Evinrude Lark 50 - Issues!

Timer plate/spark advance sticky? You probably are correct in your adjustments suspicion. I would suggest you verify it is not getting water into a cylinder. I also wonder about the "rebuilding" of the carburetors. Are you sure the jets are all perfectly clean? Also, slowing down at full throttle might mean the timing is too far advanced. Have you or anyone else messed with it?

 

[bobnoxious61]

Hello All: This is my first time here. I'm glad to see I'm not the only person left with a 1972 Lark 50 Evinrude ELECTRIC SHIFT. This motor has been a challenge ever since buying it 6 or 7 years ago. My son and I have a routine in order to get it running every time, he doesn't mind because he can wakeboard when its going. So far, 2 starters,2 throttle cables,2 batteries,new spark plugs, and wires,solenoid,new gas, and treatment. Our starting routine includes charging the battery and a separate booster pack, remove the cover off the motor, my son on the choke at the motor, and me at the key.Pump the ball till its stiff, my solds the gas down all the way. First couple of tries is with the choke at the key. The starter reminds me of an old Chrysler. When you turn the key it only gives you a 1 to 2 second try, then you have to wa I t for it to stop spinning, then you keep trying till the battery dies then on to the booster pack and about 5 minutes later it gets closer and closer to starting. If I'm really lucky the Beast L'il Red fires up and you give it the gas to keep it going. What a feeling of utter joy every time it starts. Not always so lucky, because if it doesn't start its back to charging the batteries and starting again. Does this sound familiar to anyone? Ha ha. Bobnoxious61 Let me know no

 

[bobnoxious61]

Hello All: This is my first time here. I'm glad to see I'm not the only person left with a 1972 Lark 50 Evinrude ELECTRIC SHIFT. This motor has been a challenge ever since buying it 6 or 7 years ago. My son and I have a routine in order to get it running every time, he doesn't mind because he can wakeboard when its going. So far, 2 starters,2 throttle cables,2 batteries,new spark plugs, and wires,solenoid,new gas, and treatment. Our starting routine includes charging the battery and a separate booster pack, remove the cover off the motor, my son on the choke at the motor, and me at the key.Pump the ball till its stiff, my solds the gas down all the way. First couple of tries is with the choke at the key. The starter reminds me of an old Chrysler. When you turn the key it only gives you a 1 to 2 second try, then you have to wa I t for it to stop spinning, then you keep trying till the battery dies then on to the booster pack and about 5 minutes later it gets closer and closer to starting. If I'm really lucky the Beast L'il Red fires up and you give it the gas to keep it going. What a feeling of utter joy every time it starts. Not always so lucky, because if it doesn't start its back to charging the batteries and starting again. Does this sound familiar to anyone? Ha ha. Bobnoxious61 Let me know

 

[bobnoxious61]

I have also replaced the coils