1956 Evinrude 15hp makes clank noise at idle

rookierobert

Recruit
Joined
Mar 21, 2007
Messages
3
i have a 1956 evinrude 15 horse that was not run for about 5 years. I replaced the plugs and impeller and it starts fairly easily. It does not idle at low but will stay running at just below the "start" rpm. any lower and it makes a clank noise and sometimes it dies sometimes it comes back. it has a 2 line tank (pressurized) and runs well at higher RPM. Any ideas on the low speed clank noise and what should the idle and high speed knobs be set to? Is there a proper setting for the shift linkage? I'm wondering if the clank is the lower unit engaging. When I reinstalled the lower unit after replacing the impeller I just inserted the rod and thightened the bolt. It shifts into for and rev nicely and runs while in gear. THanks.
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,195
Re: 1956 Evinrude 15hp makes clank noise at idle

If you are trying to describe a sneeze at idle, that just means it's too lean. Give the low speed knob a tweak to the left and see if it clears it up. Since it runs, don't worry about inital settings, it is close enough. Now just adjust each as necessary to run smoothest at slow and high speed.

The "clank" noise might be of concern. It shoudn't be clanking. That indicates something must be loose. Hope it isn't a bearing.
 

steelespike

Supreme Mariner
Joined
Apr 26, 2002
Messages
19,069
Re: 1956 Evinrude 15hp makes clank noise at idle

Most of those motors you have to remove the bolt and insert the rod then install the bolt.rod has a groove the bolt goes through.
Clank may be as simple as a latch rattling.Initial mixture settings are 3/4 turn out from gently seated.You may have to remove the knobs for the initial setting.Then adjust warm to best setting ending very slightly toward rich.Reinstall the knobs with the indicator at the midpoint.Idle speed should be about 550 rpm.
 
Top