We really need help with this engine. It is a 1960 Evinrude Lark II 40hp outboard motor on a 1959 Duratech aluminum boat.
Problem: Will not get above approx 10mph and stalls at low speeds / idle. It starts ok and idles after start if we give it some gas otherwise it stalls.
What have we done so far:
- Replaced starter
- Replaced spark plugs (put in J4C's in place of J8C's that were in there), according to manual J4C is correct plugs
- Disassembled carburetor and fuel pump and cleaned best we could with carb cleaner, though it looked very clean already
- Put in brand new gas with 25:1 fuel ratio per motor specs
- Check both cylinders for compression (both are at 120psi) and both have spark
- Installed new battery
We have done all of this and it is still having the same problem it had before we did all of this.
Funny thing is we were running out of gas yesterday and as the motor was starving for fuel it got a spurt of power picked up maybe a few mph and then stalled out as it ran out of gas.
I'm thinking it may need adjustments on the carburetor but I have no idea how to adjust, that's my next attempt but am looking for any other suggestions based on the above actions taken, etc.
Thanks in advance for any tips.
Problem: Will not get above approx 10mph and stalls at low speeds / idle. It starts ok and idles after start if we give it some gas otherwise it stalls.
What have we done so far:
- Replaced starter
- Replaced spark plugs (put in J4C's in place of J8C's that were in there), according to manual J4C is correct plugs
- Disassembled carburetor and fuel pump and cleaned best we could with carb cleaner, though it looked very clean already
- Put in brand new gas with 25:1 fuel ratio per motor specs
- Check both cylinders for compression (both are at 120psi) and both have spark
- Installed new battery
We have done all of this and it is still having the same problem it had before we did all of this.
Funny thing is we were running out of gas yesterday and as the motor was starving for fuel it got a spurt of power picked up maybe a few mph and then stalled out as it ran out of gas.
I'm thinking it may need adjustments on the carburetor but I have no idea how to adjust, that's my next attempt but am looking for any other suggestions based on the above actions taken, etc.
Thanks in advance for any tips.
