Sierra
Mercruiser Gen II Lower Gearcase Assembly Exploded View
Mercruiser Lower Gearcase Assembly Exploded View Diagram and Parts
Fits Generation II
Figure #DescriptionO.E.M. #Sierra #
1Gear Housing1623-815822A30
2Sleeve23-816573
3Coupling816597A1 18-3151
4O-Rings25-21836 18-7420
5Face Seal26-816575A2 18-2599
5AScrew, 10-32 X 5/810-806290NSS
5BStar Washer13-69432NSS
6Water Pump Body817275A1 18-3147**
7Impeller47-43026-2 18-3056
8Gasket27-817277 18-2563
9Face Plate817276 18-3122
10Gasket27-43033-1 18-2564
11Seal Carrier821759A2 18-2354
12O-Rings25-90011 18-7174
13Seal26-16977 18-2013
14Seal26-89238 18-2014
15Cover Nut824519 18-2346
16 & 17Bearing, Upper Driveshaft (1.50-1.65 Ratio)31-36387A1 18-1143
16 & 17Bearing, Upper Driveshaft (1:47-1:62 Ratio)31-33138A1 18-1193
18Shim(s)15-42637A1 18-2294
19Drive Shaft (1:47-1:62 Ratio)45-853648 18-2331
19Drive Shaft (1.50-1.65 Ratio)45-816919 18-2261
19Drive Shaft (1.84-1.98 Ratio)45-816472 *
20Impeller Drive Key28-43037 18-3293
21Shift Shaft815919A1 18-2320
22Speedometer Pickup Fitting^NSS
23Sleeve23-67370
24Seal26-89236 18-2009
25Shift Rod Bushing Assembly23-815921A21 18-2353
26O-Rings25-36318 18-7440
27Retaining Ring53-29641 18-4295
28Dowel Pin17-43044
29Seal26-45577 18-2944
30Gasket12-19183 18-2945
31Plug22-67892A1 18-2375
32Pin17-37972-1
33Pinion Bearing31-42647A1 18-1117
34Pinion Gear43-828072A2 18-2206>
35Washer12-92721 18-2343
36Nut11-35921 18-3719
37Shift Crank76865 18-2130
38Shift Spool Assembly818349A1 18-2286
38A38A.Cotter Pin & SleeveNSS 1
39RetainerNSS 1
40WashersNSS 1
41SpringNSS 1
42Shift SpoolNSS 1
43Clutch ShaftNSS 1
44Shim(S)15-47397A1 18-2285
45 & 46Set, Cone & Race31-35928A1 18-1159
47Forward Gear, Inner Bearing31-30895 18-1157
47A47A.Retaining Clip, Inner Bearing NSS
48Forward Gear43-828072A2 18-2206>
49Cross Pin Spring24-30893 18-2348
50Cross Pin17-30632 18-2357
51Sliding Clutch52-824112 18-2202
52Propeller Shaft44-824110 18-2166
53Reverse Gear43-828072A2 18-2206>
54Thrust Ring681001 18-2342
55Ball Bearing30-88957A1 18-1155
56O-Ring25-31534 18-7159
57Roller Bearing31-30956 18-1158
58Bearing Carrier818763A10 18-2376<
59Seal26-14077 18-2002
60Seal26-12224 18-2076
61Tab Washer14-18323 18-2298
62Cover Nut79448 18-3751
63Thrust Hub13171 18-4220
64Continuity Washer13-42351-1NSS
65Splined Washer12-31211A2 18-3714
66Tab Washer14-31210 18-3200
67Propeller Nut11-52707 18-3700
68Carrier Anode806105A1 18-6093
Seal Kit (Not Pictured)26-816575A3 18-2646-1
1Pieces not sold separately, must be purchased as 18-2286. Kit consists of figure numbers 38a- 43
2Also available in bulk pack of 10 pieces
*Must use 18-1143
#Must use 18-1193
**For Water Pump Kit use 18-3147 Mercruiser # 817275T4
^Comes with #25
**hsng. kit # 18-3147 only= 817275T4
>Gears sold as set only
<Includes inner brg. & seals
Average Customer Review for Propeller Lock Nut - 18-3700 - Sierra
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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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Good seal
by Timothy from Canfield, Ohio on August 06, 2012
correct fit, good quality, fast shipment
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Average Customer Review for Water Coupling Assembly - 18-3151 - Sierra
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Great experience
by John from Plains, Georgia on July 09, 2014
Fast shipping. Easy selection. Was able to get the boat back on the water quickly.
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Average Customer Review for Sierra 18-3147 Water Pump Kit
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water pump was as described it worked great.
by Gerome from Robards, Kentucky on August 07, 2015
water pump was as described it worked great.
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Great Service fast ship
by David from Nantucket, Massachusetts on July 31, 2012
Ordered and recieved parts hassle free super fast shipper. I actually just placed my second order with more to come in the future. Thanks for all your help
(0 of 1 people found this review helpful)
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Water pump kit
by Lamont from Woodriver, Illinois on May 29, 2012
Very fast service and shipping, as always! Iboats is always the first place that I go for parts.
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Average Customer Review for Sierra 18-2375 - Drain Plug W/Magnet
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Perfect replacement
by Tom from Mentor, Ohio on August 08, 2016
Easy to find the right part on the web site. Exact replacement. My motor is a 79 so it is a real relief to have a source for parts.
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magnet
by Victor from Underwood, Iowa on June 15, 2015
just what I needed and the magnet is a nice feature
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Fix as expected for my Mariner 20hp
by Nick from Des Plaines, Illinois on June 05, 2015
nylon washer and fit as expected for my Mariner 20hp
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Essential Parts
by Darryl from Decatur, Illinois on November 30, 2014
An excellent replacement to worn OEM parts. After years of routine service on my lower unit, the OEM parts became worn and hard to take off and put back on. This part assembly was a perfect fit for my Merc 225 EFI.
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lower unit drain plug
by Bob from Carthage, Missouri on August 08, 2014
Exact replacement for original. Works great
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Mercury lower unit plugs
by David from Harrison Township, Michigan on October 27, 2013
lived up to my expectations
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magnet plug
by Willie from Moweaqua, Illinois on September 19, 2013
would recommend using these plug so u know. if u have a problem in lower unit
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wrong size
by David from Attalla, Alabama on August 24, 2013
wrong size
(0 of 1 people found this review helpful)
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oem fit
by Stewart from Winnipeg, Manitoba on June 24, 2013
mercury outboard
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rgschmidt
by Reuben from Emelle, Alabama on March 24, 2013
Just like original. Great!
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Heavy duty - just like the OEM
by Nick from Andover, Minnesota on August 24, 2012
Was as stout as the original, and has nice clean threads.
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Cory
by Cory from Katy, Texas on June 15, 2012
High quality product, excellent replacement for original part
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Mercury Drain Plug - Magnetic
by Michael from Mars Hill, North Carolina on January 05, 2012
Exactly as described. Fit perfectly.
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Review for Sierra 18-2375 Drain Plug w/Magnet
by a Customer on September 04, 2009
(0 of 2 people found this review helpful)
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Review for Sierra 18-2375 Drain Plug w/Magnet
by a Customer on July 20, 2009
Shipping and handling is totally ridiculous $11.00 What were they thinking?
(5 of 5 people found this review helpful)
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Perfect
by Timothy from Lakeland, Florida on May 22, 2016
Exactly what I needed
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Average Customer Review for Sierra Omc & Merc. Seal - 18-2002 - Sierra
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POOR
by Jarold from Henderson, Nevada on October 30, 2014
DID NOT RECIEVE MY PRODUCT!!!!!!!!!!!!!
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Product performs as expected.
by William from Orangevale, California on September 20, 2014
Product performs as expected and was delivered in two days!
(1 of 1 people found this review helpful)
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drive shaft seals
by Victor from Interlachen, Florida on August 31, 2013
right on time,good servis
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seals
by Daniel from Bloomington, Texas on December 02, 2011
Alway very nice products and fast shipping
(1 of 1 people found this review helpful)
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Perfect fit
by Michael from Hyattsville, Maryland on September 30, 2015
Perfect, great price, bought a bunch
(1 of 1 people found this review helpful)
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Average Customer Review for Sierra 18-3056 Water Pump Impeller
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Good fast delivery
by Doug from Sheboygan Falls, Wisconsin on August 08, 2016
Hey - I got the right parts, at a fair price in just a couple days and the process for finding them online was no big deal. What more can you ask for?
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Very satified
by Henry from Hoschton, Georgia on June 28, 2016
Could not have been better!
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Impeller worked great!
by Brian from Harrisburg, South Dakota on June 02, 2015
The impeller worked great... wish it would come as a full kit however, with gaskets and all.
(2 of 2 people found this review helpful)
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good produce as advertised
by Bruce from Killeen, Texas on April 04, 2015
Good packaging, fast shipping, fast turnover. New in package as advertised, Good quality at great price.
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Geat Product
by Jon from Fair Oaks, California on May 07, 2014
Exactly what I needed to replace my old impeller
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Impeller order
by Richard from Sneads Ferry, North Carolina on February 16, 2013
Product was delivered just in a nick of time. Arrived several days before due date. It was the right part and of very good quality and packaged properly. Thanks for the quick shipment. I have ordered parts from you before and am impressed with your return policy. I consider it the best in the industry.
(0 of 1 people found this review helpful)
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Water Pump Impeller - Sierra
by Benjamin from Dacula, Georgia on September 27, 2012
ok
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Water Pump Impeller
by James from Warrenton, Oregon on June 12, 2012
Great price and fast service!
(4 of 4 people found this review helpful)
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Average Customer Review for Sierra 18-4220 Propeller Thrust Washer
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Perfect fit
by Michael from Hyattsville, Maryland on September 30, 2015
Perfect fit
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Washer
by Harvey from Kearney, Nebraska on February 26, 2015
Fit perfect
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Average Customer Review for Sierra 18-2945-9 Drain Screw Gasket
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Good quality
by Norm from Massena, New York on September 15, 2015
exactly what I needed
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Good product.
by Dean from Honolulu, Hawaii on October 21, 2011
Satisfied with quality of the product.
(0 of 2 people found this review helpful)
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Review for Drain Screw Gasket for Johnson/Evinrude 307552, Volvo Penta, Mercruiser 12-1918
by a Customer on July 20, 2009
I wish the gentlemen that took my order would have told me that the plugs came with the gaskets? Oh well now I have have spares.
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outdrive tab
by Cory from Katy, Texas on June 15, 2012
High quality replacement part, excellent fitment into housing
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Average Customer Review for Water Pump Impeller Key - 18-3293 - Sierra
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never got item
by Tom from Fridley, Minnesota on October 05, 2012
I think I deleted your respond message. Never got the item ordered. Again my address: 6340 Quincy St NE Mpls., MN 55432 Tom
(0 of 3 people found this review helpful)
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no merchandise received
by Tom from Fridley, Minnesota on September 24, 2012
I never received the first one. I wrote you guys my right address and I still never got the second order. Please check my emails again. Bet you I wrote : 6340 Quincy ST NE Fridley, MN 55432 Thank you.
(0 of 3 people found this review helpful)
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Review for Sierra 18-3293 Impeller Key
by a Customer on March 20, 2009
(4 of 7 people found this review helpful)
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Average Customer Review for Sierra 18-2354 Carrier Seal
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plastic seal
by Cory from Katy, Texas on June 15, 2012
Excellent product, fits the housing perfectly. Decided to rebuild my outdrive and damaged this part when dismantling. high quality and direct replacement for the original.
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Average Customer Review for Sierra 18-2353 Shift Rod Bushing Assembly
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Shift Rod Bushing Assembly - Sierra
by Benjamin from Dacula, Georgia on September 27, 2012
ok
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Average Customer Review for O-Ring - 18-7159-9 - Sierra
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Nice
by Enio from Rockville, Maryland on June 13, 2013
Very good
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Average Customer Review for Ball Bearing - 18-1155 - Sierra
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It Works!
by Chris from Glen Cove, New York on August 10, 2014
Good product, made well, and at a fair price. And now my boat works!
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Average Customer Review for O-Ring - 18-7174-9 - Sierra
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Spot on
by David from Ballston Spa, New York on May 04, 2016
Perfect fit
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Average Customer Review for Sierra 18-2646-1 Lower Unit Seal Kit
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Does not appear to be whole package i viewed. did not send me diagram or schematic
by Steven from Huntsville, Alabama on June 17, 2016
Does not appear to be all seals needed
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Lower Unit Seal Kit.
by Robert from Belleville, Illinois on August 25, 2015
The seal for the gear shift shaft appears to be the same outside diameter as the Mercruiser part, but when you press it into the gearshift bushing, it cracks the plastic bushing housing. Then you have to buy a new bushing housing to replace the old. When checked with a micrometer, the seal in the kit is just slightly larger than the Mercruiser part. In addition the new seal is metal, while the Mercruiser part was encased in rubber, giving it a little more "give" when pressed in place.
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Seal kit Ordering procedure.
by Dennis from Spokane, Washington on June 11, 2013
Your Product is good. What happened to Parts Finder? It was a very useful tool for me. I asked for a part and it asked what it was for, make, model, year, serial number, horse power, etc. I had to go to another parts place online to get parts for my Evenrude. I needed coils and points. I couldn't figure out your complicated ordering process. Looking forward to doing business with you again, if I can figure out how to order parts. Thank you. PS I'm not the only person who feels this way.
(1 of 1 people found this review helpful)
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Average Customer Review for Sierra Mercury Seal - 18-2013 - Sierra
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Perfect fit
by Edward from Sugar Land, Texas on September 03, 2013
Perfect fit. Came just in time for the work/
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Average Customer Review for Face Seal & Tool - 18-2599 - Sierra
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Face Seal and tool
by Jay from Mount Arlington, New Jersey on July 02, 2016
The parts were good and worked fine. I called for help before ordering and Travis(?) was extremely helpful in getting the right part.the only problem was shipping. I ordered Jun 1, given ship Jun 3 with deliver of Jun 9. I called on Jun 8 and nothing had shipped. I was told it would ship today. Shipped on Jun 9 rec Jun 15. UNACCEPTABLE service
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Quality
by Lindsey from Woodruff, South Carolina on June 09, 2012
I only needed the tool which is essentially a depth spacer. This proved to be exactly what I needed.
(2 of 2 people found this review helpful)
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Perfect Fit
by Quinton from Weeki Wachee, Florida on July 12, 2016
Worked great
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Brass Washer
by Joseph from Monroe, New York on August 03, 2015
All good!😊
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great
by Michael from Prairie du Chien, Wisconsin on April 07, 2015
As expected
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Prop Parts
by Bruce from Medford, New Jersey on September 04, 2014
Quick Delivery
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Brass Prop Castle Washer
by Deanna from Lexington, Kentucky on June 27, 2014
High quality product
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Nice
by John from Callaway, Florida on September 27, 2013
This is a nice part however I did not need it
(0 of 1 people found this review helpful)
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olman
by Kenneth from jefferson, Georgia on June 29, 2013
fit perfict
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Q:
Need propeller shaft seal MERCURY pn. 26-98283 1983 25HP?
A:
Unfortunately we do not have a cross reference with that, you will need to contact Mercury.


Q:
Where is the 2nd seal behind this seal backwards? Do I order 2 of these?
A:
Typically these require two seals, but we will need your engine information to verify.


Q:
Will this fit my 115 mercury outboard?
A:
We will need to know the serial number and year in order to confirm.


Q:
It fit to my 150 hp force. 1990.?
A:
No this will not. It fits certain Mercury/Mariner motors. You have a retainer part number 819217.


Q:
Fit 90 hp merc?


Q:
Does this key fit a 7.5 mercury?
A:
Yes, this is a universal style made to fit most small engine types, and it will work for a general 7.5 horsepower Mercury engine.


Q:
Is this the bearing the shifter housing in type2 lower unit?
A:
This particular one is on the prop shaft. It is part #57 in this exploded view: http://www.iboats.com/Mercruiser-Gen-II-Lower-Gearcase-Assembly-Exploded-View/dm/view_id.272971


Q:
Can you tell me the thread size or dimensions on this plug? I need to be sure I use the correct gear lube adapter to refill gear lube grease on my outboard.?
A:
3/8", 16 pitch thread.


Q:
Does this replace the lower unit drain plug on an 85 HP force engine? The original needs to be removed with allen key?
A:
We can only match up by knowing year and serial/model number. Call us at the number at the top of the page with that info and we can take a look.


Q:
Will this plug fit a 75 Hp '1998 model two cycle?
A:
It should fit but match make sure to match it to the engine serial number.


Q:
Is this the gasket for the screw where the gear oil goes in the lower unit?
A:
That is right. It is designated for the drain area where the oil enters the lower unit.


Q:
I have an early 2000's Mercruiser Bravo drive mated to the 6.2 MPI engine. I just purchased this boat, it has a Mercury propeller and the/a hub shock absorber with 9 equally spaced recesses for a tab lock washer to mate with. The current washer has 6 symmetric tabs and is obviously not right, as only one or 2 of the tabs line up, and don't allow the locknut to be torqued. What is the correct lock washer? Thanks.?


Q:
Is this clip for a alpha one gen 2 lower unit?
A:
Yes these are for the Mercruiser Gen II outdrive.


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:
Does this fit a 2006 mercury optimax 225?
A:
We would need serial number to cross reference OEM number. If you can provide that contact us at the number at the top of the page.


Q:
My new prop is a 1/4 inch to far up the prop shaft. The old prop had no spacer, does this washer make the new prop fit right or do I have the wrong prop?
A:
These tab washers are for keeping prop nut secure. These do not act as spacers or anything. You will need to contact us with your motor and prop number you have for us to look into a possible issue. Call us at the number at the top of the page.


Q:
Is fit for my Mercury 75hp 4 strokes motor?
A:
We will need to know the serial number in order to match up the part.


Q:
Two gaskets?
A:
Yes this comes in a package of two.


Q:
Will this fit on my 2000 Alpha 1 Gen II SN OL465337?
A:
Yes this will work for your outdrive.


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Question & Answer Guidelines
This product ships in 1 to 3 business days.
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Most products and orders leave our warehouse in 1 business day. However, select items may take more processing time. Alaska and Hawaii orders please add 1 additional warehouse processing day.
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Your Price: $9.99
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Part # 18-3700 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • CHRYSLER FORCE F7000
  • HONDA 90301-ZW1-003
  • MERCURY MARINE 11-52707
  • PLEASURECRAFT R017066
Gear Housing/Shift Shaft Oil Seal - Sierra
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Part # 18-2009 2nd Day Air for $2 More Eligible
Shaft Size - 0.375"
Outer Diameter - 0.750"
Width - 0.250"

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  • MERCURY MARINE 26-89236 1
  • MERCURY MARINE 26-89236
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Replaces OEM part #
  • MERCURY MARINE 52-66063
  • MERCURY MARINE 52-853594T
For: Mercruiser 888 S/N 3784375 & UP, and Mercruiser #1 Units S/N 3469428 & UP
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  • HONDA 91053-ZW1-003
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  • MERCURY MARINE 31-30956T
  • MERCURY MARINE 31-30956
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Dimensions ( in )
I.D. .862
Width .139

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  • MERCURY MARINE 25-21836
  • MERCURY MARINE 25-25439
GLM 12041 replacement parts
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Part # 18-3151 2nd Day Air for $2 More Eligible
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  • MERCURY MARINE 816597
  • Sierra warrants its Water Coupling Assemblys and other engine parts to be free of defects in workmanship and materials for the life of the vessel on which they were originally installed.

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Part # 18-3147 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • MERCURY MARINE 817275T4
  • MERCURY MARINE 817275K05
For: Gen ll-Lower s/n D469859 and Up

Contains:
  • (1) 18-2354 Carrier Seal
  • (1) 18-3056 Impeller
  • (1) 18-3122 Impeller Plate
  • (1) 18-3293 Impeller Key
  • (2) 18-7420 O-Ring
  • (1) 18-2944 Seal Ring Gasket
  • (1) 18-2599 Face Seal and Tool
  • (1) 18-2564 Water Pump Base to Face Plate Gasket
  • (1) 18-2566 Face Plate to Water Pump Cover Gasket
Your Price: $4.58
Save: $2.41
(34% Off $6.99)
Part # 18-2375 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • MERCURY MARINE 10-14834A1
  • MERCURY MARINE 22-67892A1
For: Mercury/Force and Mercruiser Alpha MR/Gen II lower units
Not to be used on #1/R lower units
Your Price: $6.40
Save: $3.59
(35% Off $9.99)
Part # 18-3122 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • HONDA 19231-ZW1-003
    For: 75-90 HP MERCURY MARINE 817276
  • MERCURY MARINE 817276 1
For Alpha l - Generation 2 S/N D494569 & Above
Your Price: $438.72
Save: $164.04
(27% Off $602.76)
Part # 18-2331
Hurry! Only 1 left in stock
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Replaces OEM part #
  • MERCURY MARINE 45-853648
For: Mercruiser Gen II (1998 & up), (0L100040 & up) with gear Ratios 1.47, 1.62, 1.81 & 1.94.
Your Price: $7.99
Save: $2.50
(23% Off $10.49)
Part # 18-2002 2nd Day Air for $2 More Eligible
Shaft Size - 1.188"
Outer Diameter - 1.692"
Width - 0.250"


Replaces OEM part #
  • HONDA 91252-ZW1-003
  • OMC 320862
  • MERCURY MARINE 26-76868
Your Price: $17.98
Part # 18-3200-9 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • CHRYSLER FORCE F697140
  • HONDA 90508-ZW1-003 For: 75-90 HP
  • MERCURY MARINE 14-31210
  • MERCURY MARINE 14-816629
  • PLEASURECRAFT R096117
Package of 10
Your Price: $14.52
Save: $10.97
(43% Off $25.49)
Part # 18-3056 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • MERCURY MARINE 47-43026-2
  • MERCURY MARINE 47-43026-T2
  • MERCURY MARINE 47-43026-2
  • MERCURY MARINE 47-43026-T2
  • MERCURY MARINE 47-43026 1
  • MERCURY MARINE 47-43026 4
  • MERCURY MARINE 47-43026B2
  • CHRYSLER FORCE 47-430262
  • HONDA 19210-ZW1-003
    For: 75-90 HP
For Alpha l-Generation 2 S/N D494569 & Above
Your Price: $13.99
Save: $3.00
(17% Off $16.99)
Part # 18-2076 2nd Day Air for $2 More Eligible
No Reviews  |  Write Review  |  Ask Question
Shaft Size - 1.188"
Outer Diameter - 1.690"
Width - 0.360"

Replaces OEM part #
  • MERCURY MARINE 26-12224
Your Price: $396.86
Save: $255.53
(39% Off $652.39)
Part # 18-2261 2nd Day Air for $2 More Eligible
Hurry! Only 1 left in stock
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Replaces OEM part #
  • MERCURY MARINE 45-816919
For: All Mercruiser Alpha I Generation II Drives (with new style 18-3056 Impeller)Serial #D494569 & above.
Your Price: $21.99
Save: $6.29
(22% Off $28.28)
Part # 18-4220 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • MERCURY MARINE 12-835467 1
  • MERCURY MARINE 13171
  • MERCURY MARINE 77987
  • PLEASURECRAFT RO096116
For: Mercury / Mariner- V-6 Outboards & Mercruiser Sterndrives
Your Price: $1.88
Save: $0.90
(32% Off $2.78)
Part # 18-2945-9 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • OMC 307552
  • MERCURY MARINE 12-19183
  • MERCURY MARINE 12-19183 2
  • MERCURY MARINE 12-20260
  • MERCURY MARINE 12-20260B
  • MERCURY MARINE 12-19183B
  • MERCURY MARINE F8077
  • MERCURY MARINE F50556
  • MERCURY MARINE F8186
  • MERCURY MARINE 12-191833
Package of 2
Used in most lower units and sea water pumps
Used with 18-2244 Seal Ring Gasket
Your Price: $45.88
Save: $22.80
(33% Off $68.68)
Part # 18-2320 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • MERCURY MARINE 815919A1
For: Mercruiser Gen II
Your Price: $54.76
Save: $28.00
(33% Off $82.76)
Part # 18-2130 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • MERCURY MARINE 76865
For :All Mercruiser #1 Units R/MR/Alpha
Your Price: $498.29 (Out of stock)
Save: $93.40
(15% Off $591.69)
Part # 18-2206-1
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Replaces OEM part #
  • MERCURY MARINE 43-17064A2
  • MERCURY MARINE 43-17064A3
  • MERCURY MARINE 43-42934
For: Mecruiser 1996 & older serial number F679999 & lower.
Uses our 18-1173 forward bearing with 3.500 O.D.
(Out Of Stock)
Low Price Guarantee
Your Price: $33.63
Save: $19.35
(36% Off $52.98)
Part # 18-1193 2nd Day Air for $2 More Eligible
Hurry! Only 1 left in stock
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Replaces OEM part #
  • MERCURY MARINE 31-33138A1
For: Mercruiser Gen II (1998-up)
Your Price: $124.44
Save: $74.48
(37% Off $198.92)
Part # 18-2376 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • MERCURY MARINE 818763A10
For: Mercruiser Alpha Gen II & MR Units Housings with casting #73020C1
Your Price: $12.92
Save: $7.51
(36% Off $20.43)
Part # 18-2298 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • MERCURY MARINE 14-18323
Your Price: $4.00
Save: $1.98
(33% Off $5.98)
Part # 18-2944-9 2nd Day Air for $2 More Eligible
No Reviews  |  Write Review  |  Ask Question
Replaces OEM part #
  • MERCURY MARINE 26-45577
Package of 2
Your Price: $2.61
Save: $0.38
(12% Off $2.99)
Part # 18-3293 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • MERCURY MARINE 28-43037
  • MERCURY MARINE 28-43037
Also large O/B's
Your Price: $4.09
Save: $2.89
(41% Off $6.98)
Part # 18-2563-9 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • HONDA 19232-ZWI-003
  • MERCURY MARINE 27-43034-1
  • For Mercury/Mariner 70 / 75 / 80 / 90 / 100 / 115

  • Pkg. of 2
Your Price: $361.31
Save: $278.35
(43% Off $639.66)
Part # 18-2166 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • MERCURY MARINE 44-824110
  • MERCURY MARINE 44-66060-3
  • MERCURY MARINE 44-66060
For: All Mercruiser #1 & MR/ALPHA Units S/N 2791957 & above. Also for 165 (6 cyl.) S/N 2763442 & above.
Mercruiser Carrier Seals
Your Price: $21.86
Save: $7.13
(24% Off $28.99)
Part # 18-2354 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • MERCURY MARINE 807929A1
  • MERCURY MARINE 821759A4
  • MERCURY MARINE 821759A1
  • MERCURY MARINE 821759A3
  • MERCURY MARINE 815922A1
  • MERCURY MARINE 815922A5
  • MERCURY MARINE 821759A2
  • MERCURY MARINE 807929A2
Your Price: $4.68
Save: $2.30
(32% Off $6.98)
Part # 18-2564-9 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • HONDA 19234-ZW1-003
  • MERCURY MARINE 27-43033-1
For: Mercury/Mariner 70 / 75 / 80 / 90 / 100 / 115; Mercruiser Alpha I - Generation 2
Package of 2
Your Price: $33.26
Save: $14.23
(29% Off $47.49)
Part # 18-1117 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • OMC 387817
  • MERCURY MARINE 31-42647A1
Spring Clip - Sierra
Your Price: $1.63
Save: $1.35
(45% Off $2.98)
Part # 18-4295-9 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • MERCURY MARINE 53-29641
Package of 2
For: Mercruiser Gen II
Your Price: $18.51
Save: $7.17
(27% Off $25.68)
Part # 18-2353 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • MERCURY MARINE 23-815921A21
  • MERCURY MARINE 23-815921A17
  • MERCURY MARINE 23-815921A10
  • MERCURY MARINE 23-815921A8
  • MERCURY MARINE 23-815921A6
  • MERCURY MARINE 815921A2
Your Price: $13.08
Save: $6.37
(32% Off $19.45)
Part # 18-1157 2nd Day Air for $2 More Eligible
No Reviews  |  Write Review  |  Ask Question
Replaces OEM part #
  • HONDA 91057-ZW1-003
  • MERCURY MARINE 31-30895T
  • MERCURY MARINE 31-30895
Your Price: $28.10
Save: $23.89
(45% Off $51.99)
Part # 18-6093 2nd Day Air for $2 More Eligible
Hurry! Only 1 left in stock
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  • Zinc Anode
  • Replaces OEM part # MERCURY MARINE 806105A1
  • MERCURY MARINE 806105Q 1
  • MERCURY MARINE 806105T1

For: Mercruiser Alpha One (Gen II) (1991& UP)
GLM 11050 replacement parts
Your Price: $3.18
Save: $2.27
(41% Off $5.45)
Part # 18-2348-9 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • MERCURY MARINE 24-30893
Package of 2
For: Mercruiser 1/MC-1/R/MR/Alpha Mercruiser/Gen II lower S/N D469859 - F679999
Your Price: $60.96
Save: $49.20
(44% Off $110.16)
Part # 18-2286 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • MERCURY MARINE 818349 1
  • MERCURY MARINE 19755A2
Your Price: $13.41
Save: $6.54
(32% Off $19.95)
Part # 18-7159-9 2nd Day Air for $2 More Eligible
Dimensions ( in )
I.D. 3.855
Width .210

Replaces OEM part #
  • MERCURY MARINE 25-31534
Your Price: $31.68
Save: $17.31
(35% Off $48.99)
Part # 18-1155 2nd Day Air for $2 More Eligible
Hurry! Only 1 left in stock
Replaces OEM part #
  • MERCURY MARINE 30-88957A1
  • MERCURY MARINE 30-88957T
Your Price: $2.98
Save: $1.00
(25% Off $3.98)
Part # 18-2343-9 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • MERCURY MARINE 12-92721
Package of 2
For: Mercruiser MR/Alpha/Gen II
Your Price: $7.14
Save: $16.88
(70% Off $24.02)
Part # 18-2294 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • MERCURY MARINE 15-42637A-1
Lower Drive Shaft Bearing Shims
Contains: (1) each .002, .003, .005, .010, & .020 shims
Your Price: $2.93
Save: $2.02
(40% Off $4.95)
Part # 18-3719 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • MERCURY MARINE 11-35921
  • MERCURY MARINE 11-F694188
  • MERCURY MARINE 11-47411
  • MERCURY MARINE 11-826375
  • OMC 314730

Size: 5/8" - 18
Your Price: $4.05
Save: $5.90
(59% Off $9.95)
Part # 18-7174-9 2nd Day Air for $2 More Eligible
Hurry! Only 1 left in stock
Dimensions ( in )
I.D. .620
Width .100

Replaces OEM part #
  • OMC 326649
  • OMC 910582
  • MERCURY MARINE 25-45711
Your Price: $3.92
Save: $2.14
(35% Off $6.06)
Part # 18-2346 2nd Day Air for $2 More Eligible
Hurry! Only 1 left in stock
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Replaces OEM part #
  • MERCURY MARINE 824519
For: Mercruiser MR Alpha & Gen II
Your Price: $33.43
Save: $10.23
(23% Off $43.66)
Part # 18-1143 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • MERCURY MARINE 31-36387A1
Mariner 70 - 125 HP 4 Cylinder Gearcase Assembly Exploded View-Cross Pin - Sierra
Your Price: $1.91
Save: $1.58
(45% Off $3.49)
Part # 18-2357 2nd Day Air for $2 More Eligible
Hurry! Only 1 left in stock
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Replaces OEM part #
  • MERCURY MARINE 17-30632
Your Price: $31.94
Save: $42.05
(56% Off $73.99)
Part # 18-2646-1 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • MERCURY MARINE 26-816575A1
  • MERCURY MARINE 26-816575A3
For: Mercruiser Alpha Gen II
Kit Contains:
    ( 1 ) 18-2599 Face Seal and Tool - replaces O.E.# 26-818575A2
    ( 1 ) 18-2564 Water Pump Base to Face Plate Gasket - replaces O.E.# 27-43033-1
    ( 1 ) 18-2566 Face Plate to Water Pump Cover Gasket - replaces O.E.# 27-817277
    ( 1 ) 18-2945 Sealing Washer - replaces O.E.# 12-19183
    ( 1 ) 18-2944 Seal - replaces O.E.# 26-45577
    ( 1 ) 18-2002 Oil Seal - replaces O.E.# 26-76868
    ( 1 ) 18-2013 Oil Seal - replaces O.E.# 26-16977
    ( 1 ) 18-2014 Oil Seal - replaces O.E.# 26-89238
    ( 1 ) 18-2054 Oil Seal - replaces O.E.# 26-81646-1
    ( 1 ) 18-2076 Oil Seal - replaces O.E.# 26-12224
    ( 1 ) 18-2077 Oil Seal - replaces O.E.# 26-14077
    ( 1 ) 18-7159 Oil Ring - replaces O.E.# 25-31534
    ( 2 ) 18-7168 O-Ring - replaces O.E.# 25-48171
    ( 1 ) 18-7176 O-Ring - replaces O.E.# 25-90011
    ( 2 ) 18-7420 O-Ring - replaces O.E.# 25-21836
    ( 2 ) 18-7440-1 O-Ring - replaces O.E.# 25-36318
    ( 2 ) 18-2056 Oil Seal - replaces O.E.# 26-66302
    ( 1 ) 18-7413 O-Ring - replaces O.E.# 25-62702
Your Price: $8.39
Save: $6.10
(42% Off $14.49)
Part # 18-2013 2nd Day Air for $2 More Eligible
Shaft Size - 0.875"
Outer Diameter - 1.250"
Width - 0.188"

Replaces OEM part #
  • MERCURY MARINE 26-16977
Your Price: $5.25
Save: $1.74
(24% Off $6.99)
Part # 18-2599 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • MERCURY MARINE 26-816575A2
For: Mercruiser Alpha I Generation II
Your Price: $11.29
Save: $6.83
(37% Off $18.12)
Part # 18-2285 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • MERCURY MARINE 15-47397A1
Kit Contains: (1) each .002, .003, .005, .010, & .020 shims
Your Price: $9.32
Save: $6.67
(41% Off $15.99)
Part # 18-2014 2nd Day Air for $2 More Eligible
No Reviews  |  Write Review  |  Ask Question
Shaft Size - 0.875"
Outer Diameter - 1.500"
Width - 0.312"

Replaces OEM part #
  • MERCURY MARINE 26-89238
Your Price: $6.98
Save: $1.25
(15% Off $8.23)
Part # 18-3714 2nd Day Air for $2 More Eligible
Fits: Alpha/Bravo I (without Flo-Torq II Hub)
Replaces OEM part #
  • MERCURY MARINE 12-31211A2
  • MERCURY MARINE 12-31211A3

NOTE: Fits above product with rubber hub propellers (non-Flo-Torq II)

Your Price: $16.46
Save: $7.53
(31% Off $23.99)
Part # 18-3751 2nd Day Air for $2 More Eligible
Replaces OEM part #
  • MERCURY MARINE 79448
Your Price: $52.20
Save: $26.23
(33% Off $78.43)
Part # 18-1159 2nd Day Air for $2 More Eligible
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Replaces OEM part #
  • MERCURY MARINE 31-35928T1
  • MERCURY MARINE 31-35928A1