remanufactured powerhead break in procedure

[wvmedic]

I need some help making sense of the break in procedure. OBR's website says to do a 10 hour break in. I get that, there are 4 parts that is confusing me.

This is for a 1995 90 hp, my model is E90TLEO

It reads in one part to retorque the heads at 10 hours after cool down, in another section addressing OMC specifically. It advises to re torque the heads at 1 hour of operation, after cool down.

The next 2 things that are confusing to me are. It says to install a .002 larger main jet, I can not find a larger main jet. The other is to retard maximum timing 2 degrees with motor running greater than 4500 RPM. In their break in procedure you are not supposed to operate the boat at a consistent speed between 3000 and 4000 RPM.

So which is correct?

Thank you, Jeff

I know I ask a lot of questions folks and I apologize for that. I would be a contributor myself but, I barley know what I'm doing.

I do very much appreciate the help I do get.

 

[jimmbo]

The Evinrude Owners Manual went:
If the Engine has the VRO and it is Functioning, put a 50:1 Premix in the Fuel Tank for the First 10 hrs.
If the VRO has been removed, 24:1 for the first 10hrs, after which, 50:1 is the Ratio

First Hour
Run the motor, in gear at a fast Idle for 5 - 1- minutes. For the Remainder of that hour do not operate above 3000-3500 rpm. On an easy planing hull, it would be preferred to put the boat on Plane with Full power, and immediately reduce the Throttle to maintain 3000-3500 rpm.
Second Hour
Put the Boat on Plane, and reduce the Power to about 4300 rpm, at intervals increase to Full Throttle for Periods of 1 to 2 minutes, returning to about 4300 for a brief Period.
Avoid continuous Full Throttle for the next few hours, varying the Speed

 

[saltchuckmatt]

My uncle, former Evinrude dealer always said to vary the throttle as well. Do not keep it at one speed for more that 60 seconds.

 

[jimmbo]

Some longer periods at a constant Speed are part of the Break In Process. More Throttle, Loads the Rings, causing abrasion which removes High Spots. backing down to a Lower Rpm, for a few minutes, unloads the Rings, and a Polishing of the recently abraded Metal, occurs.
Some People have the Idea that if you will mainly be running it a WOT, or at 3/4 Throttle, that is what speed you break it in at. I suspect they are Breaking in a Replacement Powerhead every couple of Years. However, Baby it too much and the Rings will never seat correctly.

 

[saltchuckmatt]

Two different theories.... My uncle was a true motorhead and outboard guy. Learned a lot from him. I've always stuck to his rule and my outboards go a long time. Either way, good oily mix and no full speed until hour down with your hours.

Or, buy an E-tec and their already broke in when you get them...wait, they don't have new ones!

 

[wvmedic]

Thank you folks for the comments.
I am going to follow the 10 hour break in and re torque the heads at 10 hours.
As for the VRO, I am deleting it. I pulled the powerhead and there seemed to be a good bit of excess 2 stroke oil in the exhaust to me. The VRO might be okay and I have a rebuild kit for it. But, for my peace of mind. I'm pulling it and replacing it with a 88 spcl setup.

I will mix 25:1 for break in and mix 50:1 in the tank to know for sure it is getting the proper mix.

I might rebuild the VRO pump and sell it.

Thank you, Jeff

 

[racerone]

Retorque head bolts after first cool down.

 

[wvmedic]

Retorque head bolts after first cool down.

Copy that, thank you.

Jeff