spacemonkey77
Seaman
- Joined
- Nov 16, 2015
- Messages
- 62
OK so you guys helped me out on here quite a bit a while back. I certainly appreciate that. I have a 1979 25 hp Evinrude model 25904r. It’s a 2 stroke pull start. Previously I was having an issue with the engine running rough at idle but then smoothing out after it warmed up. I thought it was a temperature issue because I was only noticing it during cold weather. However since then the problem has resurfaced even in the warmer weather.
The thermostat is brand new. The coil packs and powerpack are both new! The carburetor has been rebuilt and cleaned a number of times, And I’m fairly certain it’s still clean. It has brand new gas at 50 to 1 mix! Compression was 120 psi each cylinder when I checked about five months ago.I will recheck it again
when I first crank up the motor it runs real rough and it even bumps fairly hard sometimes! It feels like it has no power and even sounds different than normal idle! What’s strange about it is that once I put it in gear and throttle the engine up it will hesitate and surge and then kicks in and runs fine! When it’s first cranked it’s almost like it may be running on one cylinder, possibly! But then the second kicks in and I have no more issues after that until the next cold start. It’s almost like something may be stuck and then when I apply power it un sticks and runs normal! Even when dropping back to idle! I have checked the spark in the past and done a cylinder drop test and everything seemed fine!
could this be the reed valves? Maybe something electrical? I would think if it were electrical in the problem would persist once returning to Idol , but maybe I’m wrong!
Thanks again for your help!
The thermostat is brand new. The coil packs and powerpack are both new! The carburetor has been rebuilt and cleaned a number of times, And I’m fairly certain it’s still clean. It has brand new gas at 50 to 1 mix! Compression was 120 psi each cylinder when I checked about five months ago.I will recheck it again
when I first crank up the motor it runs real rough and it even bumps fairly hard sometimes! It feels like it has no power and even sounds different than normal idle! What’s strange about it is that once I put it in gear and throttle the engine up it will hesitate and surge and then kicks in and runs fine! When it’s first cranked it’s almost like it may be running on one cylinder, possibly! But then the second kicks in and I have no more issues after that until the next cold start. It’s almost like something may be stuck and then when I apply power it un sticks and runs normal! Even when dropping back to idle! I have checked the spark in the past and done a cylinder drop test and everything seemed fine!
could this be the reed valves? Maybe something electrical? I would think if it were electrical in the problem would persist once returning to Idol , but maybe I’m wrong!
Thanks again for your help!
Last edited:
