2006 SX 230 Motor swap question

[stevezer0]

Hey guys - bought a 2006 SX230 last year and after a few runs out on the lake was getting water in the oil. Changed the exhaust seal in hopes of correcting this issue, took the boat out on the lake to try it out.. ran great for an hour, we go to park for a bit and after that the engine never starts again.

Spent all last night checking all the lanyard, hatch switch, all checked out fine. Eventually started checking spark and compression, and now I see the engine is firing, but not making any compression at all. 0.

So that being said, I am in the market for an MR-1. I talked to a mechanic who luckily can get to me within a week, but I have need to find an engine.. couple things the guy from the service shop told me that I was surprised, he said the magneto, stator, and the bolts for these parts were not transferrable to another engine?

Any resources on anyone who knows of an MR-1 engine for sale, I am in KY and am in need of one.

Thanks,

 

[Brad_Ct]

I replaced one of my engines with one from a 2002 FX140 the other I bought from SBT. You need to know if you have high outputs engines or not.

Never heard that the magneto, stator and bolts are not transferable before, I know I used my old ones on the new engine.

 

[Ronnie]

I am all but certain that all parts from the 992 cc mr1 are interchangeable whether the engine is installed initially in a boat or a Waverunner. The same is true for the 1,052 cc (high output) engine.

money way to match the parts is via websites like yamaha sports plaza. See the pic below.

the fact that you mechanic thinks parts are not interchangeable would have me looking for a second opinion. I’ve found pwc shops to be great at working on these engines.

somerhing else to consider is what caused your original engine to fail. If the ecm failed and is leaving valves open or closed when they should. It be o would be concerned about causing the same failure on the replacement engine.

 

[stevezer0]

I replaced one of my engines with one from a 2002 FX140 the other I bought from SBT. You need to know if you have high outputs engines or not.

Never heard that the magneto, stator and bolts are not transferable before, I know I used my old ones on the new engine.

It is definitely an HO engine.

Weird about the guy telling the magneto and stator.

I've read such conflicting info on SBT - you've been happy with yours?

 

[stevezer0]

I am all but certain that all parts from the 992 cc mr1 are interchangeable whether the engine is installed initially in a boat or a Waverunner. The same is true for the 1,052 cc (high output) engine.

money way to match the parts is via websites like yamaha sports plaza. See the pic below.

the fact that you mechanic thinks parts are not interchangeable would have me looking for a second opinion. I’ve found pwc shops to be great at working on these engines.

somerhing else to consider is what caused your original engine to fail. If the ecm failed and is leaving valves open or closed when they should. It be o would be concerned about causing the same failure on the replacement engine.
View attachment 201188

yeah you are right, i need to find the original reason why i am having this problem. I was aware of the water in the oil and was actively trying to fix it, what really blows me away though is spent 2 good runs between 7 and 8k rpm with a smooth ride, no bangs, sudden stops or anything. I drove the boat to a stop, turned off the key and now I have an engine with no compression.

What is the way to check to see if I have a bad ECM, just having the YDS?

 

[Brad_Ct]

It is definitely an HO engine.

Weird about the guy telling the magneto and stator.

I've read such conflicting info on SBT - you've been happy with yours?

I don’t have many hours on the SBT engine but it runs great, only time will tell if it holds up.

I read a post somewhere that the person stated that most of the problems with their engines is that whoever is installing them never figured out why the first engine failed and that issue made the second fail. SBT has been around for quite awhile and i honestly don’t think that if they had a really high failure rate they would still be in business.

 

[stevezer0]

That’s a reasonable point.

Took the valve cover off today and timing chain did seem to be loose - my dad (old mopar guy) thinks it could’ve jumped time, but I’m not so sure.

What’s so puzzling about all this is that I drove the boat, parked it for 30 mins and it hasn’t started since and I have 0 compression in all cylinders. Baffling.

 

[Ronnie]

That’s a reasonable point.

Took the valve cover off today and timing chain did seem to be loose - my dad (old mopar guy) thinks it could’ve jumped time, but I’m not so sure.

What’s so puzzling about all this is that I drove the boat, parked it for 30 mins and it hasn’t started since and I have 0 compression in all cylinders. Baffling.

I don’t think a timing chain issue would cause all of your cylinders to read zero compression,that sounds all bad but it may be a lot less expensive to have the engine repaired than replaced. For context the timing chain and gaskets/seals are under $100 but it takes a shop, at least the one i go to, about 10 hours to do the job. Additionally, one of my pistons was worn, so the shop recommend that i replace all four. Cylinders are about $200 each, gaskets and seals are $100 plus about 10 hours of labor.

 

[stevezer0]

I don’t think a timing chain issue would cause all of your cylinders to read zero compression,that sounds all bad but it may be a lot less expensive to have the engine repaired than replaced. For context the timing chain and gaskets/seals are under $100 but it takes a shop, at least the one i go to, about 10 hours to do the job. Additionally, one of my pistons was worn, so the shop recommend that i replace all four. Cylinders are about $200 each, gaskets and seals are $100 plus about 10 hours of labor.

Yah man I’m at that point - gonna haul it over this weekend, found a guy who can at least get to it in less than 2 weeks, which is an anomaly at this point in the season. Hoping I can potentially get a rebuild - it cranks over, just no compression so hoping the internals aren’t grenaded.

 

[finnrigged]

If the boat had sat for a LONG time before the compressiontest run day it is possible or likely that the valves are stuck open on all cylinders. Corrosion and carbon on the upper valve stem from sitting dormant for as little as a year without the motor being turned over have been known to make the valve stick open once the cam lobe rotates around opening it up. I have a great rotating motor on one that sat for years but compression is 0 to crappy. It just needs a valve job. Hopefully yours is the same case.

Also, the flywheel may or may not be swappable. There are 2 different configurations to the crankshaft that dictate the flywheel to be used on the MR1 HO motor. The stator can be used on either though so he was wrong on that. Regarding the bolts... The bolts that you need to reuse when swapping are just fine. I would hit them all with a wire wheel on a bench grinder to clean the threads all off new again so that your new threadlock compound gives you the correct torque specs.