Stringer Outdrive Swap

[KRH1326]

Hi Guys,

I have been offered the leg from a 1974 165 HP elecctric shift off of a straight 6.
My set up is 1976 235 HP e/s on a V-8.

I had come across some info awhile back about what could be swapped with what. I think it had to do with the upper ratio's. I just can't find it again, yet.

Does anyone know if this swap would work?

I am diving back into google search now, any replys would be greatly appreciated.

Thanks Fellas

 

[WizeOne]

Re: Stringer Outdrive Swap

I'm sure the ratios are different. That is a big enough issue. The real issue is whether that replacement leg is a high or low profile leg.

 

[KRH1326]

Re: Stringer Outdrive Swap

HI WizeOne,

How've you been?

It too is a lowprofile, like mine.
We have been measuring various parts and everything seems to be OK.
The trunions are same size and location, as are the ball gears.

It is the ratio's that are the hang up, I think. For the life of me, I wish my memory wasn't so bad.

At some point the number of teeth in the upper changes. I can't remember if it was the 4 cyls and 6 cyls were the same but different from the 8's; or if it were the 4's that was odd man out.

I fear that the 8's were the different ones.

Dimension wise they seem interchangable.

I have to go feed the kids, then I can get back to searching.

 

[Lyndy]

Re: Stringer Outdrive Swap

Hmmm, and I thought it was the lowers that were the same in that year series drives and it was the Uppers that changed in ratio. High or low not mattering. Oh well..

 

[zbnutcase]

Re: Stringer Outdrive Swap

Yes it will physically interchange with yours; since I quit working on those 10yrs ago I can't remember the ratio differences, sorry. 'nutcase

 

[KRH1326]

Re: Stringer Outdrive Swap

OK Guys,

This is NOT gospel, it is taken from charts in a Seloc manual:

1974 165 HP upper 21.19 lower 15.23 total .72 overall 1.39

1976 235 HP upper 21.16 lower 15.23 total .86 overall 1.16

I do not understand how the ratio numbers work and why they are in decimal format and not 1:1.5 or 10:1 format.

But seeing the uppers on both are different numbers, I think it's safe to assume that I couldn't use the upper. If the lowers are the same, I should be able to use the lower as a spare.

Would I be able to use the 165 HP leg ( including the lower ) with a rebuilt 21.16 upper? Meaning using the exhaust housing, pump parts, shafts, etc?

Hey Lyndy- I think you have the right of it about upper vs. lower.

I am not hung up on grabbing this leg "just to jury rig or to make a needed repair." I am just trying to figure if it is worth grabbing for a spare, should the mud hit the fan down the road.

Thanks

 

[Howard Sterndrive]

Re: Stringer Outdrive Swap

I should be able to use the lower as a spare.

yep

Would I be able to use the 165 HP leg ( including the lower ) with a rebuilt 21.16 upper?

yep, or a good used 21/16 upper.

 

[KRH1326]

Re: Stringer Outdrive Swap

COOL!! Thanks guys.

That is why Iboats rule, and the rest drool!

 

[bruceb58]

Re: Stringer Outdrive Swap

1976 235 HP upper 21.16 lower 15.23 total .86 overall 1.16

I do not understand how the ratio numbers work and why they are in decimal format and not 1:1.5 or 10:1 format.

The numbers 21.16 means there are 21 teeth on one gear and 16 on the other.

To get the total ratio you do 21/16 * 15/23 = 0.86

Overall = 1/0.86 = 1.16

Or the number you seem to want to see:

1:1.16

 

[KRH1326]

Re: Stringer Outdrive Swap

Hi Bruce, thanks for the explanation. And thanks to Howard Sterndrive, because once upon a time a few weeks or months ago, he too tried to explain it to me.

OK so if my overall is 1 : 1.16 , that means for every crank revolution, my prop turns 1.16 revolutions?

What is the total of .86 telling me? I guess I should be asking what Total and Overall mean. Aren't they synonyms?

I see you all laughing at me, ....STOP IT!!

 

[justchange]

Re: Stringer Outdrive Swap

I wanted to thank you all for this post. I now understand my stringer better.-------Thanks again.