Boat may be in the shop for the whole summer

[NautiqueJeff]

The gasket should look like this.

Also, here's a link to the correct thermostat at NP.

https://www.nautiqueparts.com/produc...-gasket-gm-tg/

[The NY Dad]

Thanks Jeff, and everyone else for the help. Thats what my old gasket looked like I was just wondering about that small hole on the left side of the gasket by the bolt hole. There is no opening in the housing or manifold that matches up with it, so I guess that gasket may be used on various models and one of them may have a passage that lines up with it.

I made a gasket, didn't put that hole in it installed a new thermostat. I decided to just run it for an hour on the fake a lake at idle and watch the temp. It ran at 164-172 for about 10 minutes the went up to about 189, I was just about to shut it down and the temp started coming back down and went back to normal range. It ran like that for about another 15 minutes and it started climbing again. This time it went to 192 and threw DTC EMWT 1415 stage 1 code ,so I shut it down.

After researching that code on the internet my son in law found that it is a common problem with 2015 PCM engines may not be a real problem and may need a reflash at the dealer, from what he found out it happens a lot after extended slow running, so as soon as we can do it, its going back in the water and run it, monitor the temp and see what happens.

If the problem comes back we found a dealer training manual on the axis wake boat forum that goes over what to check for various codes and I think how to check it ( have to read more). We will try that and see if we can troubleshoot all the sensors. If we trouble shoot it and come up with nothing I'm going to suggest we just run it and watch the temp when it gets to 185 shut it down for awhile, go for a swim eat lunch or something and let it cool. It would be a pain to run it like that, but it's better than putting it in the shop the whole summer, then we can put it in the shop around the end of October, its already been in the garage too much.

[Fast351]

Something else to check is the raw water pickup hose connections. Even a very small leak can cause the raw water pump not to pump water at idle. By running the boat on a fake-a-lake you're pressurizing the intake and might be masking a problem.

[The NY Dad]

Sorry I haven't been on to let you know how things worked out. We had a death in the family, and we were out of state for awhile. We put the boat into the shop while we were gone because we had gone as far as we could go with it. The stalling and not restarting problem was a bad electric shift / throttle control box. Overheating they flushed the whole system and checked it all over found no problems, They did download the latest software to the ECM which the dealer told me corrects some sensor problems they have had. They lake test it and had no problems so we shall see on the overheating if its fixed or not.