Vintage Mark 55e Drifting Idle

[dbuffington]

Hi Folks!

Our Mercury Mark 55e (probably 1957), which we bought over the winter, is having idle issues...

- When cold, the motor starts easily, with no choke and with the idle lever set 3/4 full.

- The motor will not idle without stalling, cold or warm.

- As time passes, the minimum idle speed gets higher and higher.

- After about 90 minutes running, the motor will not run at anything less than 1/2 throttle. If it dies, it will not restart.

- There is a small, but steady stream of water coming from the tell tale.

Any suggestions?

Thanks!
Dave

 

[Yepblaze]

Re: Vintage Mark 55e Drifting Idle

Service the magneto, fuel pump, and carbs.

 

[dbuffington]

Re: Vintage Mark 55e Drifting Idle

Service the magneto, fuel pump, and carbs.

Thanks! The fuel pump and carbs were rebuilt over the winter. What do you suspect the magneto is doing?

Thanks again!
Dave