Which prop (3 or 4-blade) for a 18.5 ft Alicraft 18 Norwind with Mariner 90 2T

walleyehed

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IMG_0311[1].PNG Proper view of center of wake..there is no wake :))
Just a std old 150 on an old 19ft Lund.
 

Sea Rider

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Who's pictures are those original poster or Walleyead ? Seems that we?re still on the stage determining if OB sits at he sweet height. When an OB sits there, the middle wake produced at rear of lower leg is near flat even at plane.

With 1-2 up still under max 5500 wot range by 400/500 rpm.

Happy Boating
 

GreedyMuffin

Petty Officer 3rd Class
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Getting the prop tomorrow. I will perhaps go to the boat after school if the weather is nice.

Will take the picture of lower and higher plate as you wanted. I can measure it as well.

I honestly do not think it is the engine. I am wondering if I want to take the cheap comp. Set with me, to see.. Will also get the prop tomorrow.

I do not think the engine would start on first try so easily. (Fast idle up some, push the key + choke) if the PSI was low/bad.

Can perhaps film how the engine starts up after a few days without use.

So I'll check it out tomorrow, or the day after.

Thank you all again!
 

Texasmark

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Dec 20, 2005
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searider The engine is like your picture number two. I have checked it. It seems to be a decent height at least.

This is screenshotet from a video I had, so excuse the poor quality.

I can take a better picture from behind once I get the opportunity to test the boat again.

Again, thank you all for your help!

"On any "V" hull with no pad, lower eng. to level, boat on trailer. Lay a 2x4 or straight edge of some sort on bottom at keel, trim av plate to parallel. With it there, measure back from bottom point at keel to front of/L.E. of gearcase, for every 7" back you want av plate 1/2" higher. so if it's 16" back, av plate should be close to 1" above boat bottom."


My boat got some sort of keel in the front, but stops. (see picture in link, it is only google drive, no need for download or etc.)

With no pad? Can you explain a bit further to me? I understand everything until the marked area. Do you mean inches, or cm?

Link for google drive photo album: https://photos.google.com/share/AF1...?key=LXhrWlJHelFSNnZzRFQzZ3g0NUxVV0xfVHRzVmdB

Thank you all again! Sorry for any inconveniences I might have started due to my lack of English understanding.

If that's your wake, looks mighty good to me.
 

Texasmark

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Dec 20, 2005
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Proper view of center of wake..there is no wake :))
Just a std old 150 on an old 19ft Lund.

Looks like mine...in my Avatar, with 60 fewer ponies and no rooster...transom had a steep slope and I ran out of trim before I could get to blow out and the ****'s tail. I could however on my Ranger and 115 tower/Laser.
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,544
Proper view of center of wake..there is no wake :))
Just a std old 150 on an old 19ft Lund.

Looks like mine...in my Avatar, with 60 fewer ponies and no rooster...transom had a steep slope and I ran out of trim before I could get to blow out and the ****'s tail. I could however on my Ranger and 115 tower/Laser.
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,544
Looks like mine...in my Avatar, with 60 fewer ponies and no rooster...transom had a steep slope and I ran out of trim before I could get to blow out and the ****'s tail. I could however on my Ranger and 115 tower/Laser.

What the ?????????????? I punched the post button once and immediately this mess rolled by me. Somebody put a bug in the software as my postings are otherwise taking a long time to post and the "working" flag stays on forever.
 

GreedyMuffin

Petty Officer 3rd Class
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Jul 1, 2016
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I do not know what sort of prop the 17P is, but it looks to be in pretty good condition. Only a few small places lost a little bit of paint. No scratches or bents or anything like that. For 35 USD it was a steal!

EDIT: The "working" thingy after posting is there for me too. I just refresh the site via "F5" on the keyboard. :)
 
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GreedyMuffin

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I am quite dumb.. It is a E-chance prop 13 1/4 x 17P for Mercury. (Stands 60HP on it, but it the teeths are excatly the same as my 90HP props, and he had it on a 90HP)

Are those E. Chance propellers any good compared to other prop. manufactures like Stiletto, Mercury etc. I have no idea myself, thus asking. :)
 
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GreedyMuffin

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Going to test the compression tomorrow with a cheap "biltema" tester I had laying around. Probably a coiple of years old.
 

Sea Rider

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GreedyMuffin;n10381091[COLOR=#252C2F said:
][/COLOR]
Are those E. Chance propellers any good compared to other prop. manufactures like Stiletto, Mercury etc. I have no idea myself, thus asking. :)

E.Chance is a Taiwan based Company, manufacture standard alum, SS props for different OB brands, can't tell if better or worse comparing to other brands. Stiletto is a type of prop for racing, if not mistaken ? Can go for same diam/pitch prop as current one, say to a 16 pitch in any other brand of your prefference whether alum or SS to pull wot revs towards max 5500 rpm.

Happy Boating
 

GreedyMuffin

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Found a great deal on a 13 1/2 x 17 balistic. Are these cupped, will these be heavier to drive compared to a stock 17P alu

These are often much heavier than what the pitchs says due to cupping ans what not. :)
 
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Sea Rider

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Any prop you decide to buy will need to be tested on a wot spin as usually loaded, preferably on flat water cond. Ideal is for OB tu run at least middle range towars max range, which personally preffer. A cupped prop is better than a non one.

Happy Boating
 

walleyehed

Admiral
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Jun 29, 2003
Messages
6,767
Who's pictures are those original poster or Walleyead ? Seems that we?re still on the stage determining if OB sits at he sweet height. When an OB sits there, the middle wake produced at rear of lower leg is near flat even at plane.

With 1-2 up still under max 5500 wot range by 400/500 rpm.

Happy Boating

Actually, best efficiency is a bulge in center of wake which is present with a std alum prop if engine height is correct-for general boating applications.
 

GreedyMuffin

Petty Officer 3rd Class
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Jul 1, 2016
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Something is off..

The engine is not installed in center, going to change that.

Top speed is 28/29 knots with 1 person and all the props basically after more testing. The RPM was at 5400 with one. Ideal condition. Flat water, no wind etc.

I tested the engine while hot. The comp. is pretty even. Forgot to see the length between the lower plate and the over plate on the UW-house/gearhouse.

All in all, pretty disappointed.. Thinking about selling the engine/boat..
 

GreedyMuffin

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A 2004/2005 Mercury 125 HP two-stroke 2+2 engine in decent condition, a little rust on some bolts (as mine got) but nothing major.

Is that a bullet-proof engine? They still sell my 90HP it seems like, but no other OB any higher.

How much are these using under WOT? Mine uses 38/40L top, - 800 RPM: 30-32L, - 1800 RPM: 18-20L. (If the top is 5800) it is from a test I saw. Norwegian for Askeladden 505 or 515 I believe.

I think I got 18 knots at 3500. The engine is then using around 18-19L a hour.

Check the fotos of the wake(s) for both WOT and cruising: https://photos.google.com/share/AF1...&key=SUZGY1dHdHBjVWlUTjFYMUJBZnliQUVYSkJqNFZn
 

Sea Rider

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Last color pics says much more than black/white ones. Middle wake at speed is darn flat throughout the whole extension with no water hump at back which is fine, assume rear pic was shot when water cond were near flat, right ?

How's OB doing at close turns at speed on flat calm water cond ? any prop aeration ? if none lower leg height is correct. What's the max HP-OB transom rated for ? probably you're asking too much out of that under powered OB if that happens to be so, specially if boat it's a heavy one...

If with X prop OB runs at 5400 wot revs, with more load or passengers will achieve way less wot rpm. Can you test with 2 up to check how much wot rpm decreases.

Happy Boating
 

GreedyMuffin

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Can test with 3 + alot of gear tomorrow in "bad" weather (5-7 m/s wind and rain). Going to spend the weekend in a cabin just by the ocean.

The latest pictures are on the bottom of the album, you can see there that it was flat all around. Very calm!

The boat is only 500KG + engine, fuel and people. That that heavy..

Most were run with 70/75 Evinrude back in the day.

When i tested four guys + gear, the boat went on plane very easily. And that was with WOT rpm at 4900. So I do not think it is underpowered.

Going to take a look pn that 125 soon perhaps.

How much more are that engine drinking? If I can do 3800 and 20 knots, would the other engine use lomore at tge same speed but lower RPM?
 

Sea Rider

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Assumed was under powered as have not specified max HP, N? of passengers. Is there a tech plate that states so. Max boating fun is achieved when OB runs at max wot rpm range as usually loaded.

One thing is boating with a fixed weight and maximized prop running max wot range, other is adding more boaters to the equation. One adult can lessen wot revs by as much as 250-300 rpm.

My combo weights in total 500 Kg, that's boat, OB, fuel, water, beers and 2 adults up, with maximed prop OB achieves 5900 rpm, 100 more from max wot range. No way will add a third boater as will drop my nice max wot range towards middle, don't want to needlessly force my underpowered OB.

New 2 strokes OB's running wot guzzles around 12% (gallons per hour) of its HP, old ones around 10%, that's while medium loaded running at max wot rpm range on calm waters.

With 4 up and gear with current tested prop running at 4900 rpm is running already at the lugging side of min 5000 wot rpm for that 90.

Happy Boating
 
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