User Tag List

Results 1 to 5 of 5
  1. #1
    Join Date
    Mar 2015
    Location
    Harrison, TN
    Posts
    30
    Thanks (Given)
    0
    Thanks (Received)
    3
    Likes (Given)
    2
    Likes (Received)
    4
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)

    Need a new lower unit opinions on SEI drive vs repairs please

    Hello All,

    I hope your all surviving the winter. I live in the Chattanooga area and while home off my ship for the month of December it was unusually warm and had my 18 out numerous times. The Tenn River is in my front yard and was calling my name so River (her name) my Golden Retriever and I went boating as the wife was not into it.

    Long story short can happen any time of year I hit an underwater log or stump submerged mid-channel and severely bent my skeg and beat up the prop some as well. I was due to sent the prop out over the winter to be tweaked, now it has to be repaired and tweaked.

    I am not sure if the skeg can be straightened enough without breaking it off to work for me. I have been watching lots of youtube videos on that. I know that new ones can be welded on but they are never as strong as original I hear. If you have at least an inch of material left you can buy stainless slip on replacement skegs online. Two things that are in the back of my mind about both of those options. Most of my experience is with high performance outboards at 100 mph and wondering if the same is true with a 18 Donzi. I have a 393 Ford stroker motor we figure making at least a solid 400 hp with an original 1993 OMC Cobra drive. The whole drive only has about 350 hrs total on it. Right now it runs upper 60's hoping for a solid 70 maybe a little more once I get the prop dialed in this year and add headers. If I put the slip on skeg it is obviously fatter and at higher speeds wonder how much it might slow you down or possibly disrupt the water flow at 60 plus and create handling or blowout problems? I have seen them on some bass boats and not sure if that is something to worry about? If I weld it on would worry if weaker making a turn at high speed and having it break off and ruin my day as well. Does anyone have an an opinion on either option before I ask my next question about drives.

    I have been looking at buying a whole new lower unit shell only my upper is fine and changing out all the guts to the new one. Or I have talked with SEI in Florida where they assemble them and for probably less money buy and complete new unit and just bolt it on. I have done research about them and read many mixed reviews more positive than negative. They have a killer no questions asked 3 year replacement warranty that is hard to beat. I spoke with a factory guy and asked about the strength of unit compared to the OEM factory OMC, He said their gear teeth were thicker than the original ones which made then stronger as well??? I would like to believe him.

    I do not abuse my drive as I don't come out of the hole fast usually or launch the boat on a regular basis wave jumping and power in back on which I know is hard on drives. I do put the peddle to the metal so to speak usually in a controlled conditions MOST of the time LOL to keep the drive in one piece. So does anyone here have an SEI drive Mercruiser or OMC replacement and have any options of them on a high performance boat? Good or bad would love to hear any or all opinions.

    Thanks Dave



  2. #2
    Join Date
    Apr 2001
    Location
    Western Pennsylvania
    Posts
    3,882
    Thanks (Given)
    48
    Thanks (Received)
    92
    Likes (Given)
    184
    Likes (Received)
    378
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    All I can say is when I purchased a 23ft stingray it had the SEI lower that was 3 + years old behind the 502MAG-415hp and survived. China is good at copping things!
    Checkmate 2002 Convincor 270 496 MAG-HO

    2003 Cougar 22MTR w/300xs SOLD
    90 21Skater w/300xs - sold
    98 STV Euroski w/280 - sold


    2006 Trailblazer SS 6.0l 395hp

  3. #3
    Join Date
    Dec 2001
    Posts
    9,503
    Thanks (Given)
    23
    Thanks (Received)
    270
    Likes (Given)
    191
    Likes (Received)
    1975
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    HeeHee Thicker gears ..... Calls for a redesign.....longer case... different gear count......Root and tip of gears.......I don't know.......If ya shaft an;t bent weld a skeg to it......I know a place going out of business.... that might have a lower unit ......Cobra drive ford motor...... not sure of cid......

  4. #4
    Join Date
    Mar 2015
    Location
    Harrison, TN
    Posts
    30
    Thanks (Given)
    0
    Thanks (Received)
    3
    Likes (Given)
    2
    Likes (Received)
    4
    Mentioned
    0 Post(s)
    Tagged
    0 Thread(s)
    Quote Originally Posted by Dave S View Post
    HeeHee Thicker gears ..... Calls for a redesign.....longer case... different gear count......Root and tip of gears.......I don't know.......If ya shaft an;t bent weld a skeg to it......I know a place going out of business.... that might have a lower unit ......Cobra drive ford motor...... not sure of cid......
    I might have mis-quoted Here is the wording from SEI email: The gears we use are actually a little stronger than OEM. We use a lower tooth count which increases the thickness of the tooth making it stronger.

    Also if you care to PM me or post the information of where and the name of the shop going out of business is I might check them out just in case. Your the 2nd person to tell me to weld it at the speeds I am going they thought would not be a problem. Anyone else with first hand information about SEI for future reference would still be appreciated Thanks Dave S from Dave F

  5. #5
    Join Date
    Jul 2005
    Location
    AZ
    Posts
    2,752
    Thanks (Given)
    327
    Thanks (Received)
    218
    Likes (Given)
    4895
    Likes (Received)
    2386
    Mentioned
    1 Post(s)
    Tagged
    0 Thread(s)
    Ive had sei on both my motors for over 12 years at least haven't had a problem with either..and I'm not easy on them.



    Michael
    LETS GO BRANDON.... LETS GO BRANDON

    Sometimes I talk to myself...then we both just laugh and laugh

    '84 Checkmate Convincor

  6. Thanks Fulltilt thanked for this post

Similar Threads

  1. Replies: 19
    Last Post: 09-15-2012, 12:35 PM
  2. Yamaha Jet Drive Lower Unit similarity
    By ZeeCapitan in forum Jet Boats, V-Drives and Stern Drives
    Replies: 8
    Last Post: 06-06-2009, 10:40 PM
  3. 86 2.4 lower unit ,do i have to have the pin on top of drive shaft?
    By camaro7081 in forum Technical Discussion
    Replies: 5
    Last Post: 12-28-2005, 05:30 PM
  4. lower unit repairs
    By bigmotor in forum Props, Setup, and Rigging
    Replies: 2
    Last Post: 07-28-2005, 10:57 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •