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Blown engine...Need some advice

Oh man, that looks like a piston hit! I hope I'm wrong! If I am right, the piston is no longer attached to the crank/rod, meaning at least a major rebuild. I have no idea how many labor hours that entails, but it probably ain't cheap. I really hope I'm wrong!!!!!!!
 
Scary !!! As in I have the same year boat with the same hours !!
 
Oh man, that looks like a piston hit! I hope I'm wrong! If I am right, the piston is no longer attached to the crank/rod, meaning at least a major rebuild. I have no idea how many labor hours that entails, but it probably ain't cheap. I really hope I'm wrong!!!!!!!
Yeah, the mechanic was saying by the time they do a rebuild and the comparable costs I'd be better with a new engine under warranty for 2 years.
 
Cost depends on which way you go new or used and who will do the work, you, Yamaha or a third party.

I think the least expensive way to go would be to find a used Waverunner with the same engine and replace it yourself. Your markets prices will probably be different but I have yet to see such a Pwc for less than $8k in mine. Just getting a used engine on line would be cheaper still but I have yet to see one on sale.

If you want a warranty consider reaching out to sbt, small block technologies, they will make you ship them a core but their engines are warranted for at least one year, two of you pay a small premium. You'll still need to do some wrenching on your end to remove and reinstall the engine. Pwc shops around me charge $100 per hour, I estimate 3 to 5 to remove it and the same to reinstall it however this is probably low and does not account for packing, drop off, pick up and or testing.

Check out Yamaha sports plazas site thy are base in Seattle you may be able to determine a ball park figure if you decide to go with new parts.

Good luck and please keep us posted as to what Yamaha says. I have a 2010 242 ls as well so I'm hoping the scope of the problem is limited.
 
If a mechanic told me I "blew a spark plug", I wouldn't use them....unless a spark plug actually blew out of the engine maybe.

Didn't someone on here have an engine rebuilt by a PWC shop a while back? That's probably the direction I would go if it were me.

Hope you can get back on the water fairly quick!
 
Very sorry to hear about this and like many, it makes me concerned. That said, there are countless 1.8L Yamaha engines out there and problems like this are very rare but do happen as they do with any manufacturer. Please keep us updated and also post your location. Most forum members are the hands-on type and I wouldn't be surprised if you got some volunteers to help you pull the engine and put it back in if that is what it is going to take. Best of luck.
 
Looks like a bad rod bearing let the piston travel too high and it struck the plug or wrist pin bearing etc but a timing chain would not let the piston travel any more than it usually does UNLESS the Piston broke a valve and that hit the plug , a timing chain can cause that scenario.
Going back and looking at the damage to the electrode it appears a stronger metal that just a piston hit that plug so I would be leaning toward a broken valve doing that caused by the chain breaking or slipping time
 
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Agree this looks like the result of a broken valve. Wish you luck and thanks for keeping us posted. I think @itsdgm had his engine rebuilt but I don't remember the details and whether there is a connection here.
 
This is probably a good time to pass along some pointers that I always follow, In no way am I implying that these caused the issue with this engine but any one of them could cause one for you.
Here are some things to think about with any 4 stroke engine used in a boat.
Always start the engines before you launch, run them a few seconds and then turn them off.
Always follow a strict warm up procedure.
After idling for about a minute I gradually increase my rpm's so that I get on plane and stay there at a moderate speed for another few minutes before increasing the speed of the boat.
After that I usually take care to kick it in the butt and ride hard all damn day.
After the boat is on the trailer, start the engines and let them run for 40 to 60 seconds. Do not rev the engines out of the water, nothing good can come of it .
When the first 1800 engines were put on the market I was informed that people were revving the engines out of the water and causing the flywheels to come loose from the crank shaft.
This created a major recall, just an example of what can occur with no load on the engines.
Fore stroke engines are a lot more complex than 2 stroke engines, remember the exhaust system has water in it, when the engine is off some of the exhaust valves are OPEN this allows for water vapor from the exhaust system to rise up the exhaust system and condense in the combustion chambers, Rust or corrosion can follow so starting the engine and warming it up slowly can save you from a stuck valve, if just one valve sticks open and the piston strikes it you have a major issue.
Also revving the engine out of the water can get a valve to float and do the same thing. I put over 650 hard hours on a 2010 supercharged 1800 engine with only one trip to the dealer for a new heat sensor, I have 315 hours on two 2014 1800 engines now with no issues so far. It works for me so I stick with it. It will probably work for you also.
 
Ok, this thread is keeping me up at night. So, what you guys are saying is I should sell my boat in 2019 before the warranty runs out?
 
Ok, this thread is keeping me up at night. So, what you guys are saying is I should sell my boat in 2019 before the warranty runs out?
No shit. I've got a 2010 with over 200 hours!!
 
I have a SBT rebuilt MR1 motor with about 3 years and 100 hours on it, and knock on wood it is still performing flawlessly. I have even had oil diagnosis checked a few times, and everything continues to look good. Out the door, including several hundred in unrelated extras, total bill from Yamaha dealer was $4700.
 
Here's the estimate from mechanic #1. Taking it to Yamaha tomorrow for a second opinion.


Technician Comments: There is a $250 core charge if the engine we have to return to the Remanufacturer is not


able to be repaired.

1 t 1 Premium Engine Package AR240 HO $3,495.00 $3,495.00

4 t 41-LFR6A 6668 SPARK PLUG 10/PACK $10.89 $43.56

1 t 1 AR 240 Starter $214.95 $214.95

1 t Core charge long block assembly. $250.00 $250.00

1 t HAZMAT-Engine & Drive Flhazmat Disposal Fee - Engine Oil & Gear Lube $6.00 $6.00 $4,009.51

16.00 Shop Labor Technician: <Not Assigned> $120.00 $1,920.00 $1,920.00

Shipping Charges $150.00

Shop Supplies $35.00

Job 3 (Estimate) Total $6,114.51
 
Couple of piddly things I'd question, why can't you use the old starter, and why a 10 pack of spark plugs (only need 4).
 
Couple of piddly things I'd question, why can't you use the old starter, and why a 10 pack of spark plugs (only need 4).


Technician Comments: Motor would not turn over. Found only 4 volts coming from starter. Cleaned up battery


terminals and still has 4 volts at starter. Pulled spark plugs and found #4 plug was beat

up pretty bad. Will need engine block replaced.
 
@Nashvegas i think we all feel for you here. It's really hard to diagnose and estimate damage and related cost here on a forum without seeing the engine in person.

But if it was me, I would take it to a shop that works on waverunners/pwc's. I truly believe that they will look at it from a repair perspective rather than a total engine replacement aspect which imho dealers tend to steer you to. However, like I stated earlier, it's hard to understand exactly how much damage your engine actually suffered.

Also, if you have moderate mechanical skills and of course a weekend, you could pull / re install the engine yourself and save a ton of $ in labor.
 
@Cobra Jet Steering LLC - you said no revving out of the water...what about when flushing the engines?

I was always taught to start engines, flush, turn off water and rev the engine and few times to clear out the water.

Am I doing this wrong?
 
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