What Prop?

[1stgenbird]

I just bought a 1973 19ft Silverline yesterday with a Mercruiser 165hp. The 3-blade prop is a bit dinged so I want to get a replacement.

The numbers on the prop are 48-5842244 19p. I know the pitch is 19 but can I tell what prop I should get by those part numbers?

I have never owned a boat with a sterndrive so I am not familiar with then yet.

Thanks

 

[Oshkosh1]

Re: What Prop?

I run a 21P 14" Quicksilver prop on mine. I find the 19P I have good for towing tubes/boards etc...but the 21 and 23Ps better for just "cruising". These engines should operate WOT between 39-4200 RPM...depending on load/boat weight. Prop accordingly.

I think this probably will get more help in the "prop" forum...

 

[wellcraft-classic210]

Re: What Prop?

You may want to chack prices & consult PROP MD http://www.propmd.com/

I found they have great prices and can probably offer some good advice as well.

 

[1stgenbird]

Re: What Prop?

Just touching on this topic again.

After researching props over the past few days, I still have questions. The prop sites like propmd.com don't seem to list props for my year and model Mercruiser, 1973 MC-1 165hp.

iBoats seems to have the largest selection.

I see references to two-piece props. Are they interchangable with one piece? I'm not sure if I have a one or two piece prop on.

 

[steelespike]

Re: What Prop?

I think you are referring to props with separate hubs. Not an expert on these but one advantage is that once you have the hub you can try any prop that fits the hub at a slightly lower cost per prop. Brands don't interchange.
I feel it complicates the prop picture a little For instance I believe that at this moment there is a company fazing out to a different hub.
There was some discussion a while back that indicated some hubs are difficult to remove the hub to change props.
If your not likely to be fiddling with props once your settled as some do. I would buy a conventional prop.
If you can get us your present performance wot rpm and gps speed We can help evaluate your setup.
also it may be cost effective to have your prop repaired.Then you could get us accurate numbers to see if a prop change is needed.
Prop selection is pretty straight forward. If your dealing with props intended for your motor/drive the key number is the pitch.
The diameter will be correct for that particular prop. as you study the props you may notice that generally as pitch goes up diameter goes down.

 

[jestor68]

Re: What Prop?

The 14.5 X 19 pitch is pretty much a "standard" prop size you find on a lot of boats. Before buying a new one, you need to test run that prop(size) to insure that the motor turns up to the proper rpm at full throttle (4200-4600).

Most new props are of the replaceable (rubber) hub variety. They are a direct replacement for your older prop.

They come with the hub "kit" which includes the replaceable rubber hub and all the hardware needed for installation. You can remove all of the old hardware down to the thrust washer.

If your rpm's are in the proper range, I recommend the Solas Rubex 14.5 X 19 (same size as your old prop) for the best bang for the buck. It comes with the hub kit included in the price shown in the iboats prop section.

These props fit all years of Mercruiser Alpha 1 drives(4-3/4 gear case, 15 spline shaft).

The Solas Rubex is interchangeable with the Quicksilver Flo Torque system(for what that's worth).

 

[1stgenbird]

Re: What Prop?

I ended up ordering a Solex Rubex that arrived yesterday. I installed it today and the aft spacer included in the kit does not fit, not even close. I ended up using the old one. Nice looking prop, though and I like the idea of the two piece system.

 

[Bondo]

Re: What Prop?

I ended up ordering a Solex Rubex that arrived yesterday. I installed it today and the aft spacer included in the kit does not fit, not even close. I ended up using the old one. Nice looking prop, though and I like the idea of the two piece system.

Ayuh,.... Unless I'm mistaken, the aft bronze piece is what hooks the propshaft splines to the prop...

If so,... What/ Why didn't it fit,..??

 

[1stgenbird]

Re: What Prop?

Operator error. Once I started to tighten the prop nut to the correct torque, it began to pull the prop onto the shaft enough that the new aft spacer would engage the splines.

However, once I got it all torqued to the proper 55 ft lbs, the prop hits the anode. Not sure why since the new prop is the same pitch as the old one.

 

[1stgenbird]

Re: What Prop?

Operator error. Once I started to tighten the prop nut to the correct torque, it began to pull the prop onto the shaft enough that the new aft spacer would engage the splines.

However, once I got it all torqued to the proper 55 ft lbs, the prop hits the anode. Not sure why since the new prop is the same pitch as the old one.

I see that I can trim the anode so it's time to get out the grinder.