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  1. #1

    Default What is the top of the lower unit called? where do i get a new one?

    Hi everyone

    I found a problem with my Mercuray outboard. As you can see in the picture below, the top piece of the lower unit (the lid?), where the impeller rests, has take a lot of damage:

    - How important is this piece? Will water get in my gears or schould the seal around the shaft hold? Only the top part has taken damage, the seal is underneath the piece(from this angle) and free of damage.
    - What is this piece called?
    - Is it possible to replace it, and where can i buy a new/used replacement?


    Click image for larger version. 

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    Thank you

  2. #2
    Join Date
    Sep 2010
    Posts
    17,405

    Default Re: What is the top of the lower unit called? where do i get a new one?

    Do you have a model # , horsepower or year ??

  3. #3
    Join Date
    May 2007
    Posts
    9,205

    Default Re: What is the top of the lower unit called? where do i get a new one?

    That looks nasty. There are a pair of seals where the drive shaft goes into that (unit) and I can't even see any definition that they are there.

    Depending on what model you have it may be challenging to find an new unit. You do need to post up whatever details you have on the motor (model, year, horsepower, picture of the cowl, whatever).
    Graham

    A "professional" is someone who gets paid for their work - it doesn't necessarily mean they are good at it :)

  4. #4
    Join Date
    Sep 2003
    Location
    New Tripoli, PA, USA!
    Posts
    16,194

    Default Re: What is the top of the lower unit called? where do i get a new one?

    Graham:

    Nice to see you posting again.

    Jeff

  5. #5

    Default Re: What is the top of the lower unit called? where do i get a new one?

    Quote Originally Posted by racerone View Post
    Do you have a model # , horsepower or year ??
    Thank you for your respons.

    I have a serial number: 9543323 - but I cant find anything on it.
    It is aMercuray 2 stroke engine with 4hp.
    I dont know what year it is from.

    I schould have includede this in the original post Sorry.

  6. #6

    Default Re: What is the top of the lower unit called? where do i get a new one?

    Hi

    Thank you for your reply

    It is a Mercury 2 stroke engine, 8cc with 4 hp. I havent been able to find anything on the serial number sofar: 9543323

    There was no indication of a seal on the top part of the unit. The drive shaft went stright into the waterpump, through the impeller and then through this unit. Underneath the unit there is a oil seal which seems intact. There was a gasket between the unit and the "gearbox" which broke and also needs replacing.

    Here are two more pictures of the unit. I really hope it helps?

    Click image for larger version. 

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    Ps: what the limit on picture size on this forum?

  7. #7
    Join Date
    May 2007
    Posts
    9,205

    Default Re: What is the top of the lower unit called? where do i get a new one?

    Here's a link (on this site) of the parts diagram for your motor. http://www.marineengine.com/parts/me...ng-drive-shaft

    Some of the parts you may require may no longer be available. There is a chance you could find a complete lower unit from a salvage place such as Twin City Outboards, they have "tons" of recycled parts (but they are not cheap) http://www.twincityoutboard.com/

    ***edit*** just noticed that this site has two gear housings in stock, brand new - but at 200 bucks might be more than the motor is worth...

    (hello Jeff - yes been quite busy with a number of endeavours for a while. Spending a little more time at home now behind the keyboard )
    Last edited by galamb; 02-13-2019 at 12:38 AM.
    Graham

    A "professional" is someone who gets paid for their work - it doesn't necessarily mean they are good at it :)

  8. #8
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    Jan 2010
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    Posts
    995

    Default Re: What is the top of the lower unit called? where do i get a new one?

    Quote Originally Posted by Platinium View Post
    Serial number: 9543323 - but I cant find anything on it.
    It is aMercuray 2 stroke engine with 4hp.
    I dont know what year it is from.
    Your engine year looks to be an 1988 model year.
    4-H.P - Serial Number Range 9506611 - 9548011 = 1988

  9. #9

    Default Re: What is the top of the lower unit called? where do i get a new one?

    Quote Originally Posted by boat_tech View Post
    Your engine year looks to be an 1988 model year.
    4-H.P - Serial Number Range 9506611 - 9548011 = 1988
    Thank you very much! Feels good to know a bit more about the engine!

  10. #10

    Default Re: What is the top of the lower unit called? where do i get a new one?

    Quote Originally Posted by galamb View Post
    Here's a link (on this site) of the parts diagram for your motor. http://www.marineengine.com/parts/me...ng-drive-shaft

    Some of the parts you may require may no longer be available. There is a chance you could find a complete lower unit from a salvage place such as Twin City Outboards, they have "tons" of recycled parts (but they are not cheap) http://www.twincityoutboard.com/

    ***edit*** just noticed that this site has two gear housings in stock, brand new - but at 200 bucks might be more than the motor is worth...

    (hello Jeff - yes been quite busy with a number of endeavours for a while. Spending a little more time at home now behind the keyboard )
    Thank you very much for your help. I was thinking a salvage place might be the best bet.

  11. #11
    Join Date
    Nov 2011
    Location
    tennessee
    Posts
    3,527

    Default Re: What is the top of the lower unit called? where do i get a new one?

    The info posted is incorrect...your motor is a Mercury branded Tohatsu from the early 2000's year. The link posted is incorrect also as are the parts listed. You need part number 369650171 about $28, the seal part #369602230 about $8 plus the gaskets and impeller....plenty of parts online to repair.
    Pappys Sales and Service
    Owner and Factory Certified Technician
    Former racer KDBA (Kentucky Drag Boat Association)

  12. #12
    Join Date
    Jan 2010
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    995

    Default Re: What is the top of the lower unit called? where do i get a new one?

    Nice catch there faztbullet... Makes me wonder how many I may have gotten incorrect over the years trying to help out online finding Mercury years and parts..

    In actually looking over the actual parts list now pointed out by faztbullet the part photoed by Platinium matches what you'd find on the Tohatsu parts guide too which you'd be better off looking at to continue ordering available part in stock, etc. with less issues....,https://www.boats.net/catalog/tohats...se-drive-shaft

    Looking over the Related Fitment of part number 369650171 in the link above says it fits the years between 2002 - 2017 for Tohatsus.

    That noticed using the latest Merc part number 46-826053t is a match too but says No Longer Available at least on this site but other sites suggests it may still be available as long as it's ordered from the Mercury factory for more $ too it seems.
    http://www.marineengine.com/newparts...+Base+Assembly
    https://www.mercruiserparts.com/826053t-housing-w-p

    ^ That mentioned always search part numbers here on this site too because they are really good at finding other Parts/Numbers/Brands that cross reference to others that fit too much like the main part in question here..,http://www.marineengine.com/newparts...num=OMC5040177

    Unless otherwise noted from faztbullet, or others on the actual year of your engine from Tohatsu...? Here's a link to an 2003 4-H.P 2 stroke that may work for you...https://www.boats.net/catalog/tohats...stroke-tohatsu
    Or here's a main list of years of Tohatsu, https://www.boats.net/catalog/tohatsu

    Here's some other parts guides from Mercury that ought to work as they match up serial number wise and lower unit images of the Tohatsus,
    http://www.marineengine.com/parts/me...ru-9589153-bel
    https://www.mercruiserparts.com/4-5-...-japan-9477830

    My apologies for any confusion on my part...Good luck.

  13. #13

    Default Re: What is the top of the lower unit called? where do i get a new one?

    Quote Originally Posted by faztbullet View Post
    The info posted is incorrect...your motor is a Mercury branded Tohatsu from the early 2000's year. The link posted is incorrect also as are the parts listed. You need part number 369650171 about $28, the seal part #369602230 about $8 plus the gaskets and impeller....plenty of parts online to repair.
    Thank you so much for this reply. A local mechanic had helped me out with identifying the motor as an "original" Tohatsu, but we still had trouble find the part numbers! This helps a lot and answers my post.

    The piece is called a Water Pump Base (Sometimes water pump housing base).
    And i can get a new one online.

    Thanks alot

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