Repowering 2010 21hp from 250 proxs 2s to 300 proxs 4s. What should I know?

[dbs1]

I'm told I'll need a complete kit for throttle, wiring, hotfoot. I've already got the smart craft gauges. What else besides different hubs for the props are needed? Fuel lines? Etc???

[dbs1]

I'm sure some have done this, yes?

[jbh3]

Post your question(s) below in the Merc 4 Stroke section for best results. Looks like Mercury engine orders are taking a LONG time between the order and dealer delivery.

[dbs1]

In my case my brother is replacing the 300 proxs off his Vexus with a 300r that luckily became available recently so I'll be using his former engine in the swap. I think Don Weed is going to give me a heads up on what is needed. Nothing is cheap!

[stevebrownfnr]

Just replaced my 2 stroke ProXS 250 on my 2012 20XS with a 2022 4 stroke. Same controls and hot foot. They dialed in demand linear on the G3 and that was all.

[21xTriton05]

I'd run the same prop and see where you're at before buying a new one.