3.7 ? ? ? ? ?

[mlb31384]

Default 3.7 lower noise what could it be ?
well i have the all so hated 3.7 lx 180hp and i have a noise in the lower end of the motor. any suggestions before winter so i know what kind of project im getting into.
this is what i do know
motor starts and runs fine, there is good compression on all cylinders, i have put about 65 hrs on this motor while its had this noise, motor has plenty of power to plain a 20ft boat and go 35mph w 6 adults, the noise is NOT a rod knock, i have good oil pressure, i was told a wrist pin or rod bearing but idk how to tell the difference.
also please dont tell me to run away or junk out my boat i am mechanically inclined just slightly inexperienced in diagnosing. i recently put a head gasket on this motor and that took 3 hrs start to finish and an oil change. im thinking if i have to pull the motor i could have it out in about the same amount of time maybe less.
i purchased this boat from a guy that said it had the noise in it all last year when he bought it and all the way until the headgasket went out on him about 2 months ago. it overheated because a hose was loose and leaked all the coolant out
Thank you for your help

 

[Bifflefan]

Re: 3.7 ? ? ? ? ?

Rod knock and rod bearing are the same thing.
If youve put that many hous on it with the knock and it still runs, more than likely its a wrist pin.
It may run for ever like that (probably not tho).
It needs a new piston and wrist pin. Not to hard of a fix, if thats all. you can do just the one if and i say IF the rest is in excellent shape. only pulling it out and removing the head and pan will tell.

 

[mlb31384]

Re: 3.7 ? ? ? ? ?

ok that doesnt sound like that bad of a job plus taking the head off while out of the boat will be a breeze .

 

[mkast]

Re: 3.7 ? ? ? ? ?

You might expect to find a little more after tear down and inspection.