Hey guys I recently bought a boat with the 700 SCI engines and NXT drives and trannys I was wondering what oil to run in the trannys and drives mercury just calls out high performance gear lube also how do I drain the antifreeze in the engines to replace that?

I run mercury synthetic gear lube for the trans. & drive, I'll buy a 5 gal. pale at a time, part #8m0078016.
I would like to know how to change the antifreeze as well and how not to smash my hands aligning the spline into the trans. when putting the drive back on?

Is the fill for the tranny right on top of the transmission? Also do you fill the outdrive until oil starts coming out the fill hole?

The fill is top dead center of trans. Fill the drive from the lower plug until it comes out the upper plug.

need to see pics of the new boat

The previous owner ran Amsoil dominator 15w-50 in the engines and Amsoil severe gear 75w-110 in the trannys and outdrives is that ok to stick with?

I know amsoil has good if not excellent products, but my previous boat was identical in power and drives as a friends and we drove them pretty close in the same way, except his is a 312 fastech with all amsoil product and mine was a 353 fastech with all merc product and he has gone through several drives and I never had one fail while I owned it for the 900+ hours we put on them. I don't know what the reason is but I have always used merc products and it seems to just work for me. Where are the pics of the new boat

Amsoil recommends 20-50 motorcycle for NXT drives.

Hi folks. I've also just bought a boat with a 700SCI and NXT drive and trans. Is there instructions available online somewhere that show how to change drive and trans fluids? Would be super appreciative for any assistance here.

I've bought the factory service manuals for the nxt drive and the 700 sci. I've looked for videos as well buy no luck. And I would also like to know an easy way to put the drive back in place. The manual is no help here.
The coolant in the closed loop system is rated for 5 years. I don't remember if there is a coolant plug on the lower portion of the block but could pull a knock sensor to drain the coolant.

The trans fills from the large plug on top of the tranny. There should be a black hose from the bottom of the trans to drain tranny fluid.