Need help trying to find out why on starboard motor only I keep melting #5 piston 4 power heads all with the same result I lose # 5 .......any help would be great!!!

Just a rule of thumb that I've seen in the past. If #1 or #2 go then it's a water problem or lack of usually. If #5 or #6 go then it's a lean mixture. If you have an EFI the ECU could be messing up. I had one on a 2.5 that took out 2 different blocks. It could be a plugged fuel filter, water seperator or the fuel pump may be intermittant and drop pressure. Check your pressure to be sure. I've seen an EFI regulator go bad too. Tom

Did this help any? Tom

Thanks Tom we will find out soon I put bigger jets in for that jug !
and have a new module on order.

Flow test your jets and have your ECU checked. They can ritchen the mixture on the 2.5's can they do the same on the 2.4?

Jon

Also, make sure you have the hose in the water jacket are. I have had some 2.4’s need an extra hose in the water jacket because the water boils and moves to fast across the cylinder not allowing it to cool enough. Second, it does sound like the Injector could be acting up, though you usually see a loss in RPM when that is the case. In the F1 boats we pull the screens out to get better flow.