ICDEDPPL thanks for the links man, I’ll definitely get the fuel
coolers tested!

ICDEDPPL Man it’s there from about 70-90 sadly, I’ve gotten better at driving it and it’s a lot better for sure. But 100-120 rides like a dream. Haven’t been able to run it harder due to this issue sadly. Here’s a video of it at the shootout

Nortech Supercat with stage 3 Mercury 700s

Ryanw10 Yes, I even had the fuel tested at the station.

It could be completely unrelated, but when I first got it the same size I’m having most of my issues with, I burned the fuel pump up first trip out. It kept throwing the relay until I replaced it twice and blew the pump.

I ran across one of the previous owners of your boat in Havasu 2021 maybe 22? Nice guy owned a body shop I believe said he broke a rocker (or some of them?) on one of the engines. I don't recall if he said he had them all done at that time or not. Totally nonrelated to your current issues but said it always ran strong for him other than that. He also made the windshields for mine and yours before I bought it. Was telling me how he painted the edges on them to make it look like actual glass and not the plexiglass if you check it out. When I met him he had already sold it to someone and not sure where it went.

IF it turns out the coolers are ok I'd bet money it sat outside and filled those f-in tanks up with water and you are the lucky recipient.

I would not bother pressure testing the tanks that will be a dead end. By a few cases of filters and start the drain and fills!

I would also question the injectors on both engines since you don't know how long they have sat with watered fuel in them. This took out two sets of mine unfortunately.

Diamond Dave yes sir I think I got it from the guy right after him there in Havasu. He said the motors had been gone through and refreshed but no paperwork. I still rolled the dice. It’s funny you mention the windshields, I thought they were actual glass so I had a guy come out to tint them just to find out they weren’t lol they look damn good though!

so if you look at the fuel setup in the picture, being there’s not a return back to the tank, for the bigger gets filter to be getting water in it straight form the tanks it would have to be coming from there. I think my next step will be adding a loop in the vent hose, and then draining a couple time like you said. Even thought about adding another filter in line to help clean it out faster and give me some more run time If that makes sense? If I was just getting it in the secondary filter after the cooler I’d think more about that being the issue.

When I had everything drained and gone through in August, one of the things we did do was injectors thankfully.

Could be non-related but it could have sat with water fuel in it? What kind of pump are you using? Mine ate two of the Aeromotives. Fairly common they burn up on their own apparently. Shop I bought my Weldon replacement at in Havasu had an ungodly pile of dead ones and refused to sell more of them lol. Hopefully the Wedons last.

Diamond Dave man I went back with aeromotive sadly, I was in a crunch so it was the quickest fix. I’ll definitely go with Wedons if I have an issue again.

Mark didn't say anything about defective coolers with the 700s, just time catching up with them. The 700s that were in my 36 were built in October and December of 2010, and the failure happened in July of 2022. Getting more than a decade of use (including saltwater) out of them is commendable in my books. Both Bob and Josh have treated me great, and I can't say enough good things about all the work they've done for me since I picked up my 36 in 2020.

I definitely can't say for sure that's the issue that you're having, but I thought I'd share my very frustrating 700 water-in-fuel-issue experience with you in hopes that it helps you out possibly. It's the only issue I ever had with the motors in the 4 seasons I ran the boat with them - they're great motors!