1.8L rebuild brake in process?

[ReelFishingSWFL]

Does anyone have any recommendations for breaking in my new 1.8 L rebuild motor. It’s a 2017 FSH 190. I’m doing the first start up tomorrow new bearing piston rings pretty much all the internals are new.. Just curious if I should do anything special before going wide open.

 

[Ronnie]

We bought 2021 Waverunners with 1.8L motors in 2021. I recall the manuals stating to increase the throttle slightly up a little past cruising speed before varying the speed between idle and cruising speed for an hour before going to WOT. The rationale, if memory serves me, is that a slow break in will allow the piston rings to settle properly and increase the engines life.

 

[FSH 210 Sport]

From your owners manual. In addition to what the manual says, my suggestion would be to run the engine at varying rpm’s within each steps’ rpm range staying at a given rpm no more than a couple of minutes at a given rpm. In step 4, go up to say 2000 rpm for a minute then back to idle for a min, then up to 2500 rpm, back to 2000 rpm, then up to 3000 rpm, back to 2500, up to 4000, back to 2500…. Just keep varying the rpm’s as you climb up to the top rpm in that section. After section 5 is complete, let’s call it section 6, I would do another hour to incrementally work up to max rpm. Like @Ronnie says, this allows the rings to seat, I’m pretty sure my car manuals have stated similar break in procedure up through 500 miles. And I wouldn’t go wide open for more than 10-15 seconds at the beginning of section 6, just a quick burst up to top speed then back down.

 

[ReelFishingSWFL]

From your owners manual. In addition to what the manual says, my suggestion would be to run the engine at varying rpm’s within each steps’ rpm range staying at a given rpm no more than a couple of minutes at a given rpm. In step 4, go up to say 2000 rpm for a minute then back to idle for a min, then up to 2500 rpm, back to 2000 rpm, then up to 3000 rpm, back to 2500, up to 4000, back to 2500…. Just keep varying the rpm’s as you climb up to the top rpm in that section. After section 5 is complete, let’s call it section 6, I would do another hour to incrementally work up to max rpm. Like @Ronnie says, this allows the rings to seat, I’m pretty sure my car manuals have stated similar break in procedure up through 500 miles. And I wouldn’t go wide open for more than 10-15 seconds at the beginning of section 6, just a quick burst up to top speed then back down.

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Thank you this is a very detailed reply.