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Mercury Outboard Lower Unit Replacement, Aftermarket or OEM parts?



Mercury 200HP EFI lower unit

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My 2002 Mercury EFI 200HP outboard motor needs a new lower unit.  At the end of last season a seal failed filling the gear housing with saltwater and by the time it was obvious the damage was done.  I knew this season was going to start with an expensive repair but I wasn’t fully prepared for the cost.  Retail for a new OEM Lower Unit direct from Mercury $5200, factory remanufactured OEM lower units cost around $3,200 at the Mercury dealership, and both come with a one year warranty.  As much as I’d like to have a new or factory remanufactured parts installed it just isn’t in the budget this season.  My next considerations were used and rebuilt lower units.  Rebuilds sell online for around $2000 and used lower unit prices are all over the board.  I’ve seen a few used listed on ebay for as low as $500.  Of course most of the used lower units I’m finding have been removed from older motors. 


Just when I thought I researched all my options someone mentioned the idea of using an aftermarket lower unit.  I had not considered aftermarket parts as an option, in fact I didn’t even know it was an option. A friend on a fishing forum told me to take a look at SEI Marine Products.  They manufacture aftermarket lower units for Mercury, Johnson, Evinrude and Yamaha outboards (they also make Sterndrives).  A brand new SEI aftermarket lower unit (SE206 replaces Mercury 2.0, 2.4 & 2.5 Liter) for my Mercury EFI 200 HP is only $795 (plus $50 shipping) and it comes with a 3 year (fault-free) warranty.  I’m a big believer in the old adage “you get what you pay for” but I have talked with more than a few people who say this company is the real deal.  I searched the net up and down looking for SEI Lower unit reviews and or customer experiences. I visited the SEI support forum, and I called to speak with them directly. I didn’t find any dissatisfied customers on the web and I’ve been told by more than a few people since I started asking questions that SEI’s products are solid.  They have only been making the aftermarket lower unit for my Mercury motor for two years. One would expect that by now there would be plenty of chatter on the web if these were failing badly. 


I need to make sure that my lower unit can not be repaired.  I took it off and put it in the pickup.  One hour of labor later and my lower unit was officially condemned; it can’t be fixed or rebuilt due to rust damage.  While I had the Mercury mechanics ear I asked his opinion of aftermarket lower units.  I didn’t expect a Mercury dealer to have anything positive to say about their less expensive competitor and for the most part they didn’t, but I was surprised that they didn’t have too much negative to say either.  I made it clear I wasn’t going to buy a new OEM or factory remanufactured Mercury lower unit do to my budget constraints. We discussed my options with regards to buying a rebuilt or used lower unit. 

Having a full understanding of all my options along with the costs and risks associated with each choice it was time to make a decision.  While I think the SEI aftermarket lower unit price and warranty are outstanding, I worry about having trouble mid season.  In that scenario I’d have to ship the lower unit back to Florida and wait for it to be serviced.  I’d end up paying shipping both ways and I’d suffer downtime which is the absolute worst case with our short New England boating season.  Buying used or rebuilt online is pretty much the same scenario except I probably wouldn’t be dealing with a company or individual with any measurable reputation.  Buying a used lower unit locally (from the Mercury dealer) doesn’t have the shipping headaches or unknown reputation risks that come with an online purchase but it also doesn’t come with a three year warranty.  The warranty aside I still decided to buy a used Mercury lower unit from the local (trusted) Mercury Dealership in Hingham MA (Bill’s Outboard) for $600.  They are a family run business with plenty of experience and integrity.  I don’t expect this used lower unit to last the life of the powerhead so at some point in the future I may be revisiting the aftermarket verses OEM lower unit decision again.  By then SEI will have had more time in the marketplace with their aftermarket Mercury lower units and I think the reliability factor will be clearer. If in a year or two I still can’t find poor SEI lower unit reviews I think I will give one a try but for now I’m happy with my decision.