Would you buy a used boat with a rebuilt motor?

[Nautique99]

How risky is this?  Anybody have experience with rebuilt motors?

[MDB1056]

Rebuilding is fine. No concerns. Understanding why it was rebuilt and good documentation of what all was done IMO is essential. Rebuilding is often the best solution as you're refreshing the original power plant in the boat, so everything goes back in as it was. Easy.  Unless you were unhappy with the original performance of the boat there's no reason you shouldn't be more than happy with a refreshed engine.  I had my 92 5.7 GM (Mercruiser) rebuilt after a head gasket failure and hydrolock. Came back looking like new. Reinstalled, connected, and it's been running like new for 450 hrs now.   Easiest way to be back on the water with fewest hassles.  

[swbca]

@MDB1056There used to be off-the-shelf rebuilt automotive engines for sale by volume rebuilders.   Is there possibly a rebuilt engine that would be a bolt in replacement for the what the 2004 Master Craft called the 350 HP EFI MCX Indmar engine ?

or are the internals in this Chevy engine unique for marine use ?

Or does anyone have a business selling rebuilt versions of this marine engine ? 

Better yet would it be possible to buy a Zero-Off compatible engine that is a direct replacement of this engine without modifying the boat except for the controls ?  ie. a do it your self upgrade for a skier with mechanical experience and a hoist.

 

Edited April 13, 2023 by swbca

[UWSkier]

I bought my 2001 with a fresh long-block 5.7 (Malibu Indmar Monsoon) that had about 100 hours on it.  I've had it since 2018 with zero issues.  Runs like a top.

[DW]

@Nautique99 The risk is who the rebuilder is, ranging from high school shop class project (if that exists in todays world) to a reputable shop or a DIY first timer.  Assuming a marine knowledgeable competent engine shop / person, no greater risk than a short block swap.

What is the issue?  Given the number of winterizing snafus, rebuild or non original engines are probably pretty common.
 

@swbca - the long block is a basic marine small block Chevy with (4 bolt main caps, marine cam, marine head gasket, brass core plugs, marine circ pump).

Edited April 13, 2023 by DW

[MDB1056]

@swbca - plenty in here can better address issues of repowering, but can include retrofitting items as you're performing major change. As to rebuilding, as @DW notes, know who you're dealing with if you're initiating the rebuild as you want it done right, or if buying a recent rebuild as I noted earlier, get the documentation on what was done, why,  by who, etc.  Good machine shops are harder and harder to come by these days so do your homework. There may well be marine crate suppliers, I honestly don't know as have never looked but would not be surprised if a Jasper or the likes had marine crate applications too. Others here would know more on that as well. 

In my case I got a bit lucky as the shop that did mine was a NAPA owned machine shop that had an outstanding reputation. I did the extraction, build a wood stand and strapped it to it, they came and picked it up, less than a week later brought it back right to my garage door. I have all the paperwork etc. and pics of all including reinstallation. Was actually a fun project.  Not hard at all on these older boats .       

    

[DW]

Michigan Motorz is a good source:

https://www.michiganmotorz.com/products/marine-engines/remanufactured-marine-engines

[BraceMaker]

2 hours ago, swbca said:

@MDB1056There used to be off-the-shelf rebuilt automotive engines for sale by volume rebuilders.   Is there possibly a rebuilt engine that would be a bolt in replacement for the what the 2004 Master Craft called the 350 HP EFI MCX Indmar engine ?

or are the internals in this Chevy engine unique for marine use ?

Or does anyone have a business selling rebuilt versions of this marine engine ? 

Better yet would it be possible to buy a Zero-Off compatible engine that is a direct replacement of this engine without modifying the boat except for the controls ?  ie. a do it your self upgrade for a skier with mechanical experience and a hoist.

The indmar MCX is a a Chevy 5.7 based engine, if you order a 4 bolt 5.7 block even if automotive and swap over the intake and exhaust manifold and the electric you're basically there.  A marine long block is going to have rust proof casting plugs (freeze plugs as some people call them) and they're all going to have 4 bolt lower ends although I'm sure you could get away with a 2 bolt.  And then typically your marine engines don't have crazy cams to avoid sucking water back off the exhaust riser at the beginning of the intake stroke.  

The internals really not that special just what's hung on it and those casting plugs.

 

I have no problems with a rebuilt but price is according.  Would I rather have a meticulously cared for boat with 1000 hours and a factory engine or a suspicious boat that had 400 hours on the factory engine and a rebuilt 100 hours ago?  The 1000 hour boat.  You had to work to destroy one of these engines in 400 hours.

[BrennanKMN]

As long as it is priced accordingly, has good documentation to backup the parts and work, and has an explanation as to why it was needed I'd consider it. 

However, I would probably try to find a non-rebuilt one first. 

 

Most of the rebuilt boats I have seen had sub 500 hours on them and are 20+ years old. I would generally assume it was a winterization failure from an inexperienced owner on a boat that didn't get much use to begin with. 

[Nautique99]

You guys bring up some great points.  Questions that I don't have answers to yet. 

 

I was looking at buying a used boat, and learned that the engine was completely rebuilt last fall.  The current owner said they blew the motor by overloading it - boat full of people and 5 full ballast bags - trying to pull a wakeboarder.  But I'm not sure what exactly went wrong in the motor, what parts had to be rebuilt, or why.  I know the work was done by a reputable engine shop, and I have the shop's contact information.  Appreciate all of your insight - I think I have to call the shop and get better information.  I know what to ask him now.  Thanks again all!

[Nautique99]

Btw, the boat is a 1997 Malibu Sunsetter LX with 1500 hours on it, before the engine rebuild.  Priced at $20,900  Located in Ohio.  (it's listed on Ski-It-Again in case anybody is interested in seeing the listing).  The price also seems high for a having a rebuilt motor.  I don't view that like a "new" motor.

[Mastercrafter]

Yes. 

[HMan66]

The seller of that boat should have all the information on the rebuild from the shop that did the work. Engines aren’t exempt from catastrophic failure no matter how well you take care of it. Parts fail, shit happens. 

[chrislandy]

12 hours ago, Nautique99 said:

Btw, the boat is a 1997 Malibu Sunsetter LX with 1500 hours on it, before the engine rebuild.  Priced at $20,900  Located in Ohio.  (it's listed on Ski-It-Again in case anybody is interested in seeing the listing).  The price also seems high for a having a rebuilt motor.  I don't view that like a "new" motor.

That does seem high, my 96 MC sold for slightly less than that at peak corona pricing (and that did have a brand new engine specialist marine in it with 150hrs on)

[LeonL]

@Nautique99. "blew the motor" is a very ambiguous term, most commonly applied to broken crank or rod, from which there us no recovery 

Edited April 14, 2023 by LeonL

[LeonL]

By the way, I can't see how an over load either by internal weight or towed load could result in an engine failure. Something else is behind the scene.  Just take a pass on this one.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

[BraceMaker]

42 minutes ago, LeonL said:

By the way, I can't see how an over load either by internal weight or towed load could result in an engine failure. Something else is behind the scene.  Just take a pass on this one.

 

Agreed boats are different than trucks you have a built in slipper clutch in the form of a prop.  More likely they had some sort of cooling system issue like a bad raw water impeller and then had the boat all loaded down and pushing it and the engine overheated.

 

Where as you can take an F150 put a 30 foot flatbed pintle hitch trailer on it load that up with a big bulldozer and then proceed to try to tow it through the mouintains and really destroy a truck.

[UWSkier]

3 hours ago, LeonL said:

By the way, I can't see how an over load either by internal weight or towed load could result in an engine failure. Something else is behind the scene.  Just take a pass on this one.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

If they had it slammed and listed for surfing, it's possible they oil starved the engine.  I'd look for something with the Diamond hull if shopping Malibu, personally.  The OG Sunsetter was on the SV23 "wake" hull, which can be an excellent ski hull if you put it on a crazy diet like @DW did with his Echelon.

[DW]

Another potential would be hydrolock if they shut the engine off while hot and still ballasted.  The boat would be sitting much lower and could possibly have sucked water back up the exhaust as the engine cooled.