1995 Prostar with Indmar 5.7L Engine Bogs Down After 20 min

[itsmetibbs]

First time Mastercraft owner here. I bought the boat from a gentleman who replaced a cracked block and never got it running right afterword. I bought it and found out he incorrectly installed the timing chain.. The chain was one link off causing all sorts of issues with the valves. I fixed the timing chain and reset my ignition timing and took it out this weekend. It was amazing.

This is my first time driving a direct drive boat, and my first time with a V8. I was amazed at the power and responsiveness. Regretfully, it only ran well for a short time. After about 20 minutes of towing tubers around, we killed the engine to switch riders. When I went to start it again, it wouldn't start. I pulled the cover and saw that we were getting fuel through the Electronic Fuel Injectors. We cranked on it for a bit, and waited, then cranked again, and waited, then cranked again.

After 5 minutes of intermittent waiting and cranking, I was just about to try and flag someone down for a tow when it started up. We kept the guys out on the tube, and started to tow them into the marina, but while towing them in, the engine wouldn’t rev above 2500 RPMs, but it sounded like the engine was running just fine, it simply lacked power.

I made a video trying to replicate the issues without any luck, but thought I'd post the video of it running normally at 3500 RPMs to see if anyone spotted anything.

https://youtu.be/h80EUg9i5UE

A friend of mine said he’s thinking it’s a fuel issue caused by the fuel pump. Any thoughts here?

[Cumminscj]

If you could see fuel spraying while trying to start then it is unlikely that the fuel pump is the cause of the no start. A clogged inlet screen on the pump tends to cause a lack of power like you are having, but not usually a complete no start. For the no start look at the spark side of things and evaluate. Could be a few things including the ignition module/pickup module or even just the coil getting old and weak. I had a coil on one that would arc to the manifold anytime the humidity got too high. So once you raised the hatch it would almost always restart and it drove me nuts looking for the issue. You can also try checking the timing. If the pickup coil is failing then you will likely get some weird results.