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Thinking about buying an older boat with the mr1?

Jgorm

Jetboaters Captain
Messages
1,286
Reaction score
907
Points
207
Location
San Diego / Colorado river
Boat Make
Yamaha
Year
2004
Boat Model
AR
Boat Length
23
Please consider this after a little history. I bought a 2004 ar230. Test drove great, engines were super clean, oil looked fine so I didn't compression test like I planned. Day one it drive fine. Day two it struggled to start. While diagnosing that I found out I have bad compression on 2+3, and water in the oil.
I considered getting an sbt engine, even after all the terrible reviews. I called them up and they strongly advised me not to use their services. I was told stories where they find a cracked block and charge the customer $100 per week until they can supply a core that complies with their rules. Stories of adding over 2000 in additional costs, or charging customers for years. He advised me to buy one from Yamaha.

Yamaha doesn't sell the mr1. I called the dealer and they only deal with sbt!

I'm pretty handy with a good understanding of engine operation, but I've never built an engine. I know that the low compression is at least partially due to an exhaust valve. I have another thread called mr1 crank, no start, or something like that if you want to follow along.

I'm hopefully buying a used engine from a fx140 today and will cross my fingers. Unknown hours and a salt water ski.

If that fails it looks like I'll figure out how to rebuild mr1s.

If you're not handy with tools and tackling large projects, think twice about buying anything with the mr1. They call it the most advanced engine in a watercraft for a reason. 5 valve per cylinder dohc!

Stick with the 1.8l boats if this sounds intimidating.
 
Ugh that sucks bad!! Sorry. That guy you bought it from knew what he was selling you. Not sure how people like that sleep at night! He took something that was supposed to be fun for you and made it a nightmare. Not cool.
 
That's a bummer @Jgorm I think we'd all be a bit PO'd if we were in the same position. I'm up in South OC and have everything that you would need for pulling the engine. Let me know if I can help in any way.
 
Sorry, I just got an 08 and so far so good, but older engines are luck of the draw. Used working engine and your old one to rebuild might be a great plan. Best of luck.

Consider someone local, it might be something simple like valve job too.
 
@Jgorm That sucks!
But let's not forget the 1.8s breaking timing chains etc. Those 1.8s may be little simpler than the amazing MR-1s but still interference engines that self destruct upon TC failure.
We like calling our Yamaha engines bulletproof but there is no such thing.

--
 
I wouldn't go Straight to saying stay away from all MR1's.
There are thousands out there that have many years and hours of life left. I'm willing to bet you got a bad one on its last leg because the previous owner didn't do the basics to take care of it.
 
There have beeen thousands upon thousands of MR1 engines put into service. Many with hundreds upon hundreds of running hours as rentals. It has proven to be an extremely reliable marine engine with just basic maintenance.

Any engine, no matter how reliable, can fall victim to an owner that doesn't do simple maintenance. It sucks that it appears the previous owner did not take care of it and dumped it on you. But its a pretty far stretch to dog ALL MR1 engines because of it.
 
I think we really don't know the history though, and it could very well be that the engine took a dump without any fault of the current or prior owner.

We just don't know.

As a recent buyer of an old mr1 I'd like to think these are indeed bullet proof, but also Murphy's law comes into play. We don't know why it failed, but it may be through no fault of prior or current owner. Stuff happens. It is a 13 year old engine operated under marine use. Yds hours and print out would be interesting to see.

I'm still hoping it's 2 stuck valves and an easy repair.
 
I wouldn't go Straight to saying stay away from all MR1's.
There are thousands out there that have many years and hours of life left. I'm willing to bet you got a bad one on its last leg because the previous owner didn't do the basics to take care of it.

Agreed. I was thinking the opposite the other day glad I had an MR1 with no timing chain issue, or oil cooler, etc.
 
I love the mr1! I'm not knocking it at all. I had an 04 r1 that was an amazing machine. I'm planning on buying a fx140 too. I've read the reports of 2000+ hours.

My warning is that IF you have a problem, it might require calling junk yards, looking for used engines that are still working, or just to send the core to sbt for repair. If you don't work on engines, or have tons of spare cash to let the dealer charge the huge mark up, deal with multiple repairs from sbt quality parts, etc then you might want to pass.

You can't go buy a new engine, they don't exist. I think you can buy all the individual parts and build it your self.
 
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