can i use muffs on 1976 40hp evinrude?

[hardwater fisherman]

i changed the exhaust cover gaskets on my motor. and i want to test my work. it is a 40604r 1976 40hp evinrude. i have used the muffs with my father on inboard motors. but i never tried it on any of my older outboards. the water bypass plate has 4 or 5 little holes in it. is this where i install the muffs? also someone told me that the muffs dont work on older outboards. thanks

 

[sutor623]

Re: can i use muffs on 1976 40hp evinrude?

Some outboards do not allow the muffs to seat over the water intake. If your muffs completely cover up the water intake on the lower leg then you will be fine.

 

[hardwater fisherman]

Re: can i use muffs on 1976 40hp evinrude?

i was able to use them. the water intake is just above the cavitation plate so the muffs where not centered over the intake. they worked well and i didnt run it that long.

 

[sutor623]

Re: can i use muffs on 1976 40hp evinrude?

They also sell square muffs that work better when the intake is right on the cav plate.

 

[hardwater fisherman]

Re: can i use muffs on 1976 40hp evinrude?

thanks i will look for a pair of square ones. the round ones did not make a complete seal.

 

[Fed]

Re: can i use muffs on 1976 40hp evinrude?

the water intake is just above the cavitation plate

I'd double check that?

 

[hardwater fisherman]

Re: can i use muffs on 1976 40hp evinrude?

it is the old style two piece gearcase and the intake sits above the cav plate.

 

[hardwater fisherman]

Re: can i use muffs on 1976 40hp evinrude?

this is an older 40 hp model. i think you will find alot of omc motors 1976 and older are like this. that is why when you see people running them in a barrel or tank they need to be deep down in there.

 

[BF]

Re: can i use muffs on 1976 40hp evinrude?

not sure about the 40hp, but my 25 hp of that vintage has it's main water pickup behind a screen in the front edge of the exhaust opening (fin like thing) that sticks down below the cav plate... it also has another pickup above the cav plate. Either way, I always prefer using a barrel or garbage can anyway. That way I can see how well the pump is doing, without adding the hose pressure into the mix.

 

[hardwater fisherman]

Re: can i use muffs on 1976 40hp evinrude?

yes mine has that as well but its pretty hard installing the muffs there.

 

[sutor623]

Re: can i use muffs on 1976 40hp evinrude?

We have put on the square muffs, and duct taped over the intake below the cav plate for motors like this. Works fine.

 

[hardwater fisherman]

Re: can i use muffs on 1976 40hp evinrude?

ok thanks