73 MERC 500 Lower Unit

[crem1]

Any chance of getting the info on a 73 MERC 500 lower unit? Is it a pin or a stainless drve shaft and how interchangeable is it with other years?
Picture of two drive shafts, the one on the right has a pin on top of it

Thanks

 

[Laddies]

Re: 73 MERC 500 Lower Unit

One is for straight cut gears and the other for helical cut gear they don't interchange if you need part numbers go to the BAM Marine site

 

[crem1]

Re: 73 MERC 500 Lower Unit

Thanks Laddies. At least can I interchange a complete lower unit?

 

[Laddies]

Re: 73 MERC 500 Lower Unit

Yes if they both have spined shift shafts there were some made with square ones but the shafts will exchange

 

[crem1]

Re: 73 MERC 500 Lower Unit

Let me get this straight, the presence of the pin can be accommodated in any scenario?
Thanks again

 

[Laddies]

Re: 73 MERC 500 Lower Unit

The pin is a spring preload that holds the helical cut gears meshed properly when there is no torque on them when power is applied to type helical cut gears that the 50HP outboard uses they pull them selves together but when the throttle is released the spring preload of the pin holds them together.

 

[crem1]

Re: 73 MERC 500 Lower Unit

That was gtreat Laddies, how about in English now, simple terms, the lower unit with a driveshaft that has a pin on it can be used used on a power head that had a driveshaft with no pin on it.?
Thanks again

 

[Laddies]

Re: 73 MERC 500 Lower Unit

Yes.

 

[crem1]

Re: 73 MERC 500 Lower Unit

You always come through with the brains and knowledge
Thanks again
Alex