Lower Unit test

[Perfidiajoe]

I would like to know the amount of Presure & vacume to put on a lower unit when testing. I will be testing a 3 liter 225 Merc. Thanks, Joe

 

[Motor Boater Bill]

Re: Lower Unit test

What I have heard is 15 psi pressure and less than that (I think 11 psi) for vacuum. I have also heard it recommended that you check pressure at 7 psi also, since old seals can seal up at a higher pressure but leak at lower.

 

[Perfidiajoe]

Re: Lower Unit test

Thanks motor boater bill, it was right there in the Merc book, I must have passed it 100 times & didn't remember. It is 10 to 15 PSI.

 

[jameservin]

Re: Lower Unit test

someone suggested to also hand turn propshaft while testing.

 

[Perfidiajoe]

Re: Lower Unit test

Thanks James, I've done that & moved the shift shaft around also, Joe