Distance from lower gear case to prop

[fishtilubleed]

Next little question how much clearance should there be between the lower case and the prop? what does the 3 blade thrust washer do?

 

[Chris1956]

So you are talking about a Johnnyrude thru the hub exhaust-style prop?

The thrust washer keeps the prop from hitting the gearcase.

The hub of the prop usually fits into the hub of the gearcase, with a tolerance of 1/8" of so.

Is that what you are asking?

 

[fishtilubleed]

Yes I found a SS prop a quick silver in the back with the correct spline but it has 1" of stand off to the gear case. I know its not correct but all we do is jug fish out of this boat. Not looking for speed or power just chase a few jugs down. I think it will cavitate from the exhaust and yes it is exhaust through prop set up.

 

[jimmbo]

has 1" of stand off to the gear case.

???
There is a lot more to prop fit age than just the spline count
Pics would be very helpful

 

[fishtilubleed]

 

[fishtilubleed]

That was a PITA

 

[saltchuckmatt]

That will destroy the prop shaft.

 

[Chris1956]

Clearly that is not correct. I have used Merc props on my Johnnyrude, and vise versa, so if the hub is the correct size and the driveshaft diameter and splines are the same, it will work. It doesn't look like your propshaft size is correct, however.

I had to grind down the inside of a thrust washer to make the Merc prop fit. There may be conversion kits avail. Modular props can use prop housings on either Merc or Johnnyrude motors.

 

[jimmbo]

No Comment...

 

[fishtilubleed]

IT goes over the prop shaft to the same place the factory prop went to but the overall length is shorter than the stock prop. It is a merc prop. I have a machine shop thought about making a sleeve that presses over the prop and then put about 3 tack welds on it.
Salt why do you say it will destroy the prop shaft? It will pull down with nut and spline washer.

 

[fishtilubleed]

Dayum jimmbo just no comment?

 

[fishtilubleed]

Took another look and the body of the props are the same length. The stock prop I cannot tell where it spaced out to in relation to the spline and treaded portion of the prop shaft. I have 3 merc props and they all 3 slide on to the same place. Makes me wonder if the prop shaft is not tweaked a little.