Prop Selection

[Duke01]

Hello all...I am a new owner of a 1978 V20 Steplift Cuddy with a 1980 200 HP Mercury outboard. The existing 3 blade prop (48-78120-18) is banged up a bit so I am looking for a replacement. Does it make sense to consider a stainless 3 blade, or 4 blade? Top speed according to the old owner was 43 mph.

I am from MI and plan on walleye fishing in Lake Erie and Lake Huron.

I would appreciate input from the group...obviously a lot of knowledge here.

Thanks, Duke

[THEFERMANATOR]

Your current prop crosses over to a entry level, 3 blade, 18 pitch aluminum prop. Most any 3 blade cheap stainless prop in a 17 pitch would be a good choice for that engine to start with. Anytime you change props, even to a prop of the same part number, you can change your wide open RPM's or top speed.

I've had good luck with Solas props in the past. For a good all around prop they do pretty good, so far all of them I've run have run smooth, and they're cheap. A 17 pitch in the 13 1/2" to 14" diameter and 3 blades would be a good all round prop.

Larger diameter props have there pros and cons, but the larger diameter normally gives decreased prop slippage so much so you have to step down in pitch to keep your wide open throttle rpm's up. 4 blades give reduced prop slippage, normally provide better cruise speeds at a given rpm, but you normally(but not always) lose some top end speed(but some boats see an increase because the prop just works better with the boat).

Propping is an artform mixxed with some guessing, and some voodoo to get what you're after. What is ideal for one person may not work for another in the same boat. All you can do is try props until you find the one that works the best, and hope you do it in as few tries as possible.

[phatdaddy]

Only thing I would add is, try working with a local merc dealer or prop shop. Most have a good idea where to start and will let u try some out before buying, like trying on shoes.

Also,let them recondition old one for a spare

Welcome to the cult, new guy buys lunch

[THEFERMANATOR]

Did a quick search, and I would say this prop would probably be a good starting point. Most with a 150-200 hp outboard say a 17 pitch is a good pitch for all around performance. Otherwise I would look at a michigan wheel Amita 16 pitch 4 blade in there stainless props with the exchangeable hub system. They hookup very well, cruise solid, and are very smooth.

https://www.google.com/search?q=1532...obile&ie=UTF-8

[THEFERMANATOR]

Originally Posted by phatdaddy

Only thing I would add is, try working with a local merc dealer or prop shop. Most have a good idea where to start and will let u try some out before buying, like trying on shoes.

Also,let them recondition old one for a spare

Welcome to the cult, new guy buys lunch

Most any good prop shop will also do this. Admiral c&b used to swap me out for no charge so long as I brought the prop back in new condition. I know general propeller in Sarasota also has some good exchange policies, they will also repitch the prop for you for free if it's close and only needs a minor tweek.

[Duke01]

Thanks guys, I truly appreciate the guidance. Step one will be starting the outboard in the spring. When I purchased the boat the motor had already been winterized. I will then follow-up with a prop purchase.

Lots of projects to do before walleye season (June, July, August...)

[Destroyer]

I have a 78 with a 200 Johnson on it. 43 seems a little slow. You might want to weigh your boat and compare it to the original specs. (allow for any gas in the tank) Waterlogged foam can add a considerable amount of weight and slow your boat accordingly.

As to the props, what TheFermanator said is good advice. Just remember if switching to a SS prop that SS flexes less than Alum, so normally you move down a pitch or two when switching. (So a 17P Alum becomes a 16P SS).

[THEFERMANATOR]

Originally Posted by Destroyer

I have a 78 with a 200 Johnson on it. 43 seems a little slow. You might want to weigh your boat and compare it to the original specs. (allow for any gas in the tank) Waterlogged foam can add a considerable amount of weight and slow your boat accordingly.

As to the props, what TheFermanator said is good advice. Just remember if switching to a SS prop that SS flexes less than Alum, so normally you move down a pitch or two when switching. (So a 17P Alum becomes a 16P SS).

His current prop is an OLD MERCURY 3 blade 18 pitch aluminum, I would expect a 2-5 mph increase in speed with most any decent stainless prop over an old tech aluminum. Aluminum has gotten better through the years, but his aint one of the better ones.

[Duke01]

Thanks Destroyer and Thefermanator...the existing prop has a bent blade and a another blade with a chip in it, so that might explain the reported max speed of 43 from the previous owner. I suspect that the speed was recorded from the dash speedometer. I am curious to see what the impact of a new prop will be and will follow-up in the summer after launch. I will note GPS speed measurements.

Regarding the weight, the brochures call out a weight of 1920 lbs, with an associated max hp of 200. Not sure how accurate that is (?). In 1989 and thereafter, the brochures noted a weight of 2300, with and an increase in max hp to 235 (if I remember correctly). Any idea which is more accurate?

Thanks, Duke

[Destroyer]

Originally Posted by Duke01

Thanks Destroyer and Thefermanator...the existing prop has a bent blade and a another blade with a chip in it, so that might explain the reported max speed of 43 from the previous owner. I suspect that the speed was recorded from the dash speedometer. I am curious to see what the impact of a new prop will be and will follow-up in the summer after launch. I will note GPS speed measurements.

Regarding the weight, the brochures call out a weight of 1920 lbs, with an associated max hp of 200. Not sure how accurate that is (?). In 1989 and thereafter, the brochures noted a weight of 2300, with and an increase in max hp to 235 (if I remember correctly). Any idea which is more accurate?

Thanks, Duke

Use the brochure that's the closest to your boat's year. Throughout the years Wellcraft was constantly modifying the hull, stringers, materials etc. so both of those brochures are probably correct. Added thickness of the transom for the extra HP, thicker stringers, larger gas tank, etc.... all of those things can and probably did change the weight.