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HP:

HP

Serial#

Sierra Prop Nut

9.9 (4-stroke Bigfoot) G760300- UP 18-3703
15 (4-stroke Bigfoot) G590000- UP 18-3703
18 5837437- UP 18-3703
20 6443973- UP 18-3703
25 6416713- UP 18-3703
35 Fits most applications. 18-3704
40 Fits most applications. 18-3704
50 Fits most applications. 18-3704
60 Fits most applications. 18-3704
65 2503991-3293183 18-3700
70 Fits most applications. 18-3704
70 A996142- UP 18-3700
75 6432901- UP 18-3700
80 2559001- UP 18-3700
85 3493913-4831998 18-3700
90 4845301- UP 18-3700
100 2484633-2836018 18-3700
100 B209468- UP 18-3700
115 2836019- UP 18-3700
125 2536210-2839368 18-3700
135 (inline) 2839369-3293233 18-3700
140 (inline) 3293234- UP 18-3700
150 (inline) 3502806- UP 18-3700
V-6 (135-300) -18-3700

HP

Serial#

Sierra Prop Nut

Refine Parts List
HP:
Price: $9.99
Save: $2.50
(20% Off $12.49)
Part # 18-3700
2nd Day Air for $2 More Eligible
GLM 21242 replacement parts
Price: $1.99
Save: $1.00
(33% Off $2.99)
Part # 18-3703
2nd Day Air for $2 More Eligible
Propeller Lock Nut - Sierra
Price: $9.74
Save: $7.65
(43% Off $17.39)
Part # 18-3704
2nd Day Air for $2 More Eligible
Sierra
Average Customer Review for Propeller Lock Nut - 18-3700 - Sierra
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Based On 2 Reviews | Write Review
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Nut
by Charles from Casper, Wyoming on June 30, 2012
The nut you sent was the wrong size. Needed to be a 1" NOT a 1-1/16" so the washer was wrong also Propeller looks OK Haven't tried it yet.
(1 of 1 people found this review helpful)
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WRONG SIZE
by BOB from Industry, Pennsylvania on July 23, 2011
I WENT THROUGH THE WEB SITE PROCESS TO ORDER THE PROP I NEEDED AND IT AUTOMATICLY OFFERED ME THE OPTION OF BUYING THE PROP NUT AND OTHER ACCESSORIES THAT GO WITH THE PROP. EVERYTHING ELSE WORKED BEAUTIFULY BUT THE PROP NUT WAS TOO LARGE. SINCE IT COULDN'T BE RETURNED IF OPENED I JUST USED THE OLD NUT AND TOSSED THE NEW ONE.
(3 of 4 people found this review helpful)
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Average Customer Review for Propeller Lock Nut - 18-3703 - Sierra
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Based On 8 Reviews | Write Review
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lock nut
by David from Columbia, South Carolina on August 02, 2016
Good product, works as advertised.
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Full StarFull StarFull StarFull StarFull Star
Locknut
by James from Pasco, Washington on July 05, 2016
Good item. Works as planned.
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Full StarFull StarFull StarFull StarFull Star
Prop lock nut
by Jeffrey from Rosemount, Minnesota on June 19, 2015
A must have when replacing a prop
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Wrong Size
by Marcus from Milford, Ohio on May 12, 2013
This was "suggested" when I ordered my prop, of course it's the wrong size so they got me for a few bucks for something I cannot use.
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Perfect fit
by Stephen from Wilmington, Illinois on June 14, 2012
I purchased this nut along with a new propeller and it fit and looks great.
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wrong nut
by Ron from Edgewater, Maryland on June 25, 2011
the prop nut that came up when I ordered the prop was the wrong nut for the prop.
(1 of 1 people found this review helpful)
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Mercury Prop Nuts
by Randall from Bangor, Maine on August 17, 2010
Great Product and Fast Shipment!!
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Review for Propeller Nut for Mercury/Mariner 11-88228, GLM 21242 - Sierra
by a Customer on October 21, 2008
Good prop nut.
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Average Customer Review for Sierra 18-3704 Propeller Lock Nut
Full StarFull StarFull StarFull StarFull Star
Based On 2 Reviews | Write Review
Full StarFull StarFull StarFull StarFull Star
Good to go
by Johnson from Millbrook, Alabama on March 01, 2015
Machine work, materials and fit were top drawer.
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Full StarFull StarFull StarFull StarFull Star
Great ser.
by Mike from Hopkinsville, Kentucky on August 16, 2013
Great
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Q:
How do i replace item?
A:
Identify the OEM number and see if it cross references with this part. If you need some assistance give us a call at 1-800-914-1123.


Q:
How do i replace item #2 speedometer tube? Does it just screw into the housing?
A:
This is a prop nut for the propeller not for speedometer pitot tube. Those tubes just install on the stern of your boat with a basic hole pattern and screw it in. If further assistance is needed call us at 1-800-914-1123.


Q:
What is the thread size?
A:
Sierra can only match it up by engine application. There are no specs on this.


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