Rebuild Break-In Proceedures

[Todd Humphreys]

The wrench that rebuilt my Johnny 75hp (1982) said he wanted me to run my motor at a constant 3800 to 4000 rpms until I burn 50 gallons of 25:1 mix. Then bring it back to him for a first service. This seems contrary to what I have read here on this site. Any comments are appreciated.

 

[Dhadley]

Re: Rebuild Break-In Proceedures

Is he going to warranty the motor? If so I'd do exactly like he suggests.

 

[Todd Humphreys]

Re: Rebuild Break-In Proceedures

Warranty yes, but 50 gal of double mix sounds a little excessive on that motor. Thats all the gas I run in six to eight months. I guess that will be a longer warranty.

 

[Dhadley]

Re: Rebuild Break-In Proceedures

I couldn't agree more about excessive. To be honest I'd be really concerned about gummimg up (coking) the rings. But, the bottom line is that if you dont follow his instructions he has a way out of any responsibility. Trust me, I've seen it happen.<br /><br />I might suggest you discuss it with him so hes aware of your (legitimate) concerns.

 

[sgtcuh60]

Re: Rebuild Break-In Proceedures

I HAVE A 98 50Hp Evinrude The Owners Manuel says 50:1 GAS MIXTURE. :First 10 minutes run engine at fast Idle only :Next 50 minutes below 3500 RPM :Second Hr. Plane boat reduce throttle to 3/4 Position Verify water pump operation and Change Engine Speed Every 15 Minutes : Next Eight hrs. verify water pump operation change engine speed every 15 Minutes do not exceed engines RPM ? Refer To Maintenance Section After First 20 Hrs. return To Dealer For Inspections and Adjustments.<br />Note My Max RPms According to Owners Manuel Is 4500 To 5500RPM @ WOT

 

[Dhadley]

Re: Rebuild Break-In Proceedures

One thing that comes to mind about the situation is that he likes to build the motors with very, very tight tolerences. Therefore the extended break-in period on double oil. Personally I dont like a real tight skirt to wall tolerence on a 2 stroke outboard. But maybe he does....