Hi all, I've been toiling over my motor for the last 7 weeks and have had no luck in getting it back to working form. I'll detail as much as I can.
Engine is an Evinrude Lark 50hp from 1974 - 50472m - I have the owners manual and have read through it many times.
I dewinterized it and got it running, ran a little rough, but nothing insane. Got it out in the water and took it out 3 times. Noting that it idled rough and would take a while to warm up but once we were out it had no issues. I did accidentally adjust low speed needles which I'm assuming is the rough idle source, I don't know what the original setting was.
Went to sell it and had no spark. After a week of diagnosis and testing I found a faulty rectifier which likely caused the faulty powerpack, damaged (melting insulation) stator and cracked ignition coils. All with the added challenge of that it was already docked and far away from the launch.
I did a full replacement of all these components and got strong spark again.
After the full replacement of these components I was able to get the motor running but it would generally catch and stall immediately. I got it running the one time in which it maintained power on its own, I pushed the throttle linkage forward and it ran like a top (mind you in neutral) and shortly died after.
Since that point I have been unsuccessful to get any signs of life, not even so much as a cough.
I noticed the ignition coils I received already had splitting insulation and replaced them and confirmed full spark but no change in its ability to start.
I have tried multiple sets of plugs and can confirm they're all sparking, the current ones don't even have a stitch of carbon on them.
I arrived at the realization that I have a fuel problem since compression has remained strong.
Yesterday I set out to try to solve it and get some signs of life I did the following
- Now that lots of gas is getting to the plugs I'm going to re-dial back the low speed needles, probably flooding it at this point, but before wasn't getting anything
- I read that with a powerpack change, timing should be adjusted, however can I set/reset timing without the motor running? Would that be enough of a problem to cause ZERO response?
- Gas has been sitting since mid june, should I get fresh gas? Starter fluid hasn't done anything either to cause a sign of life
- I am going to test the spark with a gap tester and verify that it's sparking enough.
Any help is appreciated, I feel like I'm taking crazy pills at this point, I've spent weeks and $800 to still not have a working boat, which I'm sure many can empathize with. I know I must be close but my experience is limited.
Engine is an Evinrude Lark 50hp from 1974 - 50472m - I have the owners manual and have read through it many times.
I dewinterized it and got it running, ran a little rough, but nothing insane. Got it out in the water and took it out 3 times. Noting that it idled rough and would take a while to warm up but once we were out it had no issues. I did accidentally adjust low speed needles which I'm assuming is the rough idle source, I don't know what the original setting was.
Went to sell it and had no spark. After a week of diagnosis and testing I found a faulty rectifier which likely caused the faulty powerpack, damaged (melting insulation) stator and cracked ignition coils. All with the added challenge of that it was already docked and far away from the launch.
I did a full replacement of all these components and got strong spark again.
After the full replacement of these components I was able to get the motor running but it would generally catch and stall immediately. I got it running the one time in which it maintained power on its own, I pushed the throttle linkage forward and it ran like a top (mind you in neutral) and shortly died after.
Since that point I have been unsuccessful to get any signs of life, not even so much as a cough.
I noticed the ignition coils I received already had splitting insulation and replaced them and confirmed full spark but no change in its ability to start.
I have tried multiple sets of plugs and can confirm they're all sparking, the current ones don't even have a stitch of carbon on them.
I arrived at the realization that I have a fuel problem since compression has remained strong.
Yesterday I set out to try to solve it and get some signs of life I did the following
- Tested a different fuel line from the tank
- Sprayed liberal amounts of carb cleaner into the low speed needle throats and cleaned the needles
- Drained the bowls and sprayed cleaner through the whole system, trying to dislodge any float problems
- Verified that all internal fuel lines from the engine side were clear and free from obstruction and were not leaking. This includes fuel line to pump, pump to upper carb, upper carb to lower carb. There was a small leak from the upper carb but I used a new zip tie to snug it up. That leak was relatively new to me and occured the last time I worked on it because I was fiddling with something else and bumped it with my hand.
- Replaced the whole fuel pump since it was only 20 bucks on amazon, when I removed the old one it did leak some fuel from the diaphragm so potentially it may have had its own issues.
- boat seemed to get some start action when I toggled the throttle forward as well, but nothing that resembled a typical engine cough to start. Choke open/throttle open/closed didn't make a difference.
- lots of smoke/exhaust coming out even though it's not starting.
- lots of gas blooming on all these attempted starts
- also noted there's gas coming out of the choke leaf valves I'm assuming due to the low speed needles being wide open to make sure *something* was getting through
- Now that lots of gas is getting to the plugs I'm going to re-dial back the low speed needles, probably flooding it at this point, but before wasn't getting anything
- I read that with a powerpack change, timing should be adjusted, however can I set/reset timing without the motor running? Would that be enough of a problem to cause ZERO response?
- Gas has been sitting since mid june, should I get fresh gas? Starter fluid hasn't done anything either to cause a sign of life
- I am going to test the spark with a gap tester and verify that it's sparking enough.
Any help is appreciated, I feel like I'm taking crazy pills at this point, I've spent weeks and $800 to still not have a working boat, which I'm sure many can empathize with. I know I must be close but my experience is limited.
