prop nut torque

[MACH1SCJ]

1990 evinrude 48spl ? Model E48ESLESA

Have what I belive to be a stock prop 15 pitch- my question is how tight should the prop nut be, I have not been able to find it in the book. There is the big taper washer at the gear end & what looks like a plastic or fiber washer at the nut end. The nut is a castle nut & held in place be a cotter pin. It was finger loose when I got it & I don't know if I should tighten it up more or not.

 

[Texasmark]

Re: prop nut torque

My Merc 90 says 55 ft lbs. If loose it's hard on your gear train every time you shift and can wear out your prop or splines....would take a long time but would get progressively worse.

Mark

 

[jestor68]

Re: prop nut torque

That is a minimum of 55 ft lbs for Mercury/Mercruiser.

 

[Texasmark]

Re: prop nut torque

That is a minimum of 55 ft lbs.

Not that it matters: "Place a block of wood between gear case and propeller and torque propeller nut to 55 lb.ft (75Nm)."

 

[jestor68]

Re: prop nut torque

Some manufacturers (OMC) specify 75 ft lbs; one specifies 85 ft lbs. Mercury only says a "minimum of 55 ft lbs".

If you want to stop at the "minimum" spec, so be it. We torque our Mercury/Mercruiser prop nuts at 65- 70 ft lbs.

We feel that the word minimum (the very least amount allowable) does matter.

 

[Texasmark]

Re: prop nut torque

Some manufacturers specify 75 ft lbs; one specifies 85 ft lbs. Mercury only says a "minimum of 55 ft lbs".

If you want to stop at the "minimum" spec, so be it. We torque our Mercury/Mercruiser prop nuts at 65- 70 ft lbs.

We feel that the word minimum (the very least amount allowable) does matter.

I'm quoting what's in MY service manual and I did say what engine it was for. I didn't say that was the rule of thumb for all engines. And again, I quoted from the book, note quotation marks! The word minimum was not used.

 

[jestor68]

Re: prop nut torque

The standard manual supplied by Mercury uses the term twice in paragraph 8 of the section on prop installation.

I edited my previous post ; (OMC), so that some useful information was provided for the OP in this thread.

 

[MACH1SCJ]

Re: prop nut torque

I finally found the spec. It is 120 in. lbs. then tighten to align the castle nut if needed.