Boat Maintenance - ACME 644R prop on '92 Barefoot Nautique

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ACME 644R prop on '92 Barefoot Nautique

Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Boat Maintenance
Forum Discription: Discuss maintenance of your Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=50679
Printed Date: January-15-2025 at 6:51pm

Topic: ACME 644R prop on '92 Barefoot Nautique

Posted By: MonsterSkier
Subject: ACME 644R prop on '92 Barefoot Nautique
Date Posted: June-13-2022 at 8:35am

Hey,

my 1992 Barefoot Nautique (V-Drive) with the 351 HO still has the, what i believe is the original 14x18 3-blade OJ prop.

I am looking for some more hole shot but also dont want to loose top speed. I have been reading in this forum about the Acme 328 4-blade (13x15.5 with .090" cup) beeing the right prop for my boat.

I was able to get a hand on an Acme 644R 4-blade prop (13.25x16 with .105" cup). Any concerns that the prop might handle poorly? Could it be too much for the drivetrain?

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98 Ski Nautique 196 (current)
08 Mastercraft ProStar 197 (current)
88 Ski Nautique 2001 (sold)
92 Barefoot Nautique (sold)
01 Ski Nautique 196 (sold)
93 Ski Centurion Tru Trac III (sold)

Replies:

Posted By: TRBenj
Date Posted: June-13-2022 at 9:43am

14x18 original prop would imply you have a 1.5:1 reduction and not a 1.21… but it would be best to confirm as that drastically changes the prop you’d want to run.

There are prop to rudder interference concerns on that hull as well- how much strut to prop clearance do you currently have?

Posted By: MonsterSkier
Date Posted: June-13-2022 at 10:31am

Tim, I‘ve got the 1:1 Velvet drive + the Walter V-Drive with a Ratio of 1.46-1.

I will have to measure the clearances later when I am back home.

-------------
98 Ski Nautique 196 (current)
08 Mastercraft ProStar 197 (current)
88 Ski Nautique 2001 (sold)
92 Barefoot Nautique (sold)
01 Ski Nautique 196 (sold)
93 Ski Centurion Tru Trac III (sold)

Posted By: MonsterSkier
Date Posted: June-13-2022 at 4:29pm

With the old prop I get:

1.38" clearance between the strut and the prop (shaft visible)

1.97" clearance between the tip of the blade and the hull

.98" clearance between the tip of the blade and the rudder

With the Acme 644R I get:

1.38" clearance between the strut and the prop

2.52" clearance between the tip of the blade and the hull

.00" clearance between the tip of the blade and the rudder

I could check if the shaft is fully inserted into the coupling flange. If it is, I could possibly shorten the shaft by about an inch if that's enough clearance between the blade and the rudder. I have about .4" left between the strut ending and the beginning of the cone.

Or are there any other concerns about the prop not being suited for my set up due to the reduction of 1.46:1?

Posted By: MonsterSkier
Date Posted: June-13-2022 at 4:40pm

Posted By: TRBenj
Date Posted: June-14-2022 at 9:23am

Sounds about right. You’ll want to shorten the shaft to run the 644. The only gap you need between the strut and prop is to get a puller in there… 3/8” would do it.

Posted By: MonsterSkier
Date Posted: June-28-2022 at 10:50am

The shaft has been shortened and I was able to go for a test run.

Hole shot felt pretty good but top speed isn't quite right yet.

GPS shows 45.4 mph at 5500 rpm. I am not 100% sure about the 5500 rpm since the tachometer actually started jumping above 4000 rpm but settled a few times at 5500 rpm (new to me problem since installing the D.U.I. Will have to check the wiring for corrosion).

I don't think the Acme 328 would perform any better due to the lower cup and overall dimensions. Would you stay with the current ACME 644R and avoid high rpms or try a different prop? An suggestions for a prop?

Posted By: TRBenj
Date Posted: June-28-2022 at 2:07pm

Get an accurate tach reading first, what you’re seeing is almost certainly wrong.

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