1.8L engines missing/vibrating

[Mike Byrd]

Here are 3 video links to my engines running in a 2014 212X. One is for the port engine, starboard, and both running. This is with the boat on the lift without water attached. This is a freshwater boat since new.

It appears each engine is missing out at idle based on what I am seeing with the engine rocking/vibrating and the noise all happening together. I changed plugs with a backup set (low hour used) I had to see if there was a change. I did not see any difference.

Is it possible the idle is just a little too low? I ran Seafoam through it a tank of fuel ago. When on throttle, the boat performs flawlessly. The only other thing is it seems like I can smell the exhaust more from the helm when idling around but it could just be a coincidence.

Does anyone have any ideas? Both engines are behaving similarly. The noise seems to have gotten worse this year. I checked my buddy's 2016 212x and his engines purr like a sewing machine compared to this.

 

[Sean R]

When it the last time you changes the spark plugs?

 

[Mike Byrd]

I pulled the original plugs after the first year and replaced them with a different type that Swatski recommended here on the forum. I put these low hour OEM plugs back in and ran the boat the day before these videos were taken to see if there was a difference. I did not see any. I figured I would see if anyone else had more ideas before buying another set.

 

[RobbieO]

Sounds like intermediate bearings.....

 

[David Martin]

The vibration and noise you are experiencing are the impellers rubbing against the SS liners in the jet drives. Your Starboard engine is worse than your Port. Now for the really bad news I just checked today and most Yamaha parts supply houses are 61 days out on that part and most others as well.

 

[Mike Byrd]

Is there any way to verify whether its the intermediate bearings versus the liners?

What causes the impellers to rub on those liners?

Are most people putting stainless back in or are there delrin replacements?

 

[David Martin]

I reach in access port plug grab the prop shaft and see if you can get any Play/movement in the bearings on the drive shaft. Most guys crawl under boat on trailer and can see a raised burnt mark where the rubbing occurs its usually a raised spot on the ss liner it comes from behind the ss liner in between where the aluminum housing touches the ss.

There is a great video on Youtube that is done from a Yamaha owner from this site. His noise is a perfect match to what you are hearing and seeing.

I might try the plastic liners hate to let it go 2 months ..........just doing my research now.

 

[Mike Byrd]

It looks like Yamaha went to plastic liners in 2019 in the 212x. There are a lot of common parts between my 2014 and the 2019, but several more are different than just the plastic liner and housing. Does anyone know if I can get by with just buying the new impeller housing and inserts or would I also need to swap out the transom plate and other different part numbers?

 

[David Martin]

It looks to be just the impeller housing is the only part that gets replaced......at lease on my 2013 Sx240 ho with the 1.8 engine. I show your and my part number as 6CR-R1312-00-00 impeller housing. It does get a little confusing on some sites ebay and others I am vary caucus right now looking up all the numbers...... hear is one site WSM - Your Hard Parts Source (wsmparts.com) this site list all the 66v numbers and the 6CR OEM number and they list our boats. Amazon has a housing that lists all the 66v numbers on their housing with plastic incents but it does not list our boats only jet skis I'm a little confused as well .........it seems this 155mm jet was used on ski and boat alike.

 

[Mike Byrd]

I finally got to my boat to start checking things. There is zero signs of any issues with the stainless liner or impeller. There is zero play up and down when grabbing the shaft through the clean out ports. Thanks to jetboaters.net member dan bebe who messaged me, I think I found an issue. He said he recently had something similar and it wasn't the impellers/liners but the engine coupling.

Here is a video of the starboard (worse) engine with the coupling cover removed. This should not be this loose.

Is there anything else I should check or does everyone think this is the cause?

dan bebe also said to move the engine forward to change it. It doesn't appear to be another way easier.

Has anyone upgraded the old style couplers to the new Yamaha quiet cruise couplers? I realize I would need both metal couplers and the rubber. Can these be installed in the boat?

Thanks
Mike

 

[David Martin]

Wow never thought about the coupler I new it was not the intermediate bearings because the noise go's away when boat is in the water.....the bearing would make noise in or out of water. Now the question is would the coupler go quiet in the water...........possibly because the impeller is under constant load.....no neutral on the shafts............the engine on the hose puts no load on the impellers and this could let the coupler vibrate as the engine fires under no load.

I just might have to drag out my old mechanics stethoscope for a listen, on the jets at the back of the boat and the cover housing over the couplers the stethoscope is a great tool for tracking down noises.

 

[Evil Sports]

How does it run in the water and while your up to speed? I think its sounds normal for one of these out of the water

 

[tdonoughue]

Check the parts breakout diagram on someplace like yamahasportsplaza.com or so. I am pretty sure there is supposed to be a piece of rubber in there that takes the play out but also dampens things.

 

[David Martin]

I can see the rubber coupler inside the metal coupler but not sure if the play is normal. It should lock to rotation side when water is present at lake/ocean. Running on a hose is a no load on impellers in my mind and I hope EVAL SPORTS is correct that the sound is normal for out of water noise.

 

[David Martin]

Wow I just check my coupler..........Why because I have no life(retired actually) wife visiting my daughter so no boating today!!!! Your rotation looks to be in the neighborhood of 1/8 inch to 1/4 inch........... my rotation play is around the thickness of a sheet of printer paper or less.

 

[Mike Byrd]

The member dan bebe who has been messaging me said it should be tight. He is a yamaha tech. He changes them all the time. I know mine are worn out so I am going to change these before doing anything else. Unfortunately, these are on back-order with no ETA from Yamaha so it will be a while.

 

[Mike Byrd]

My motors have the same vibrating/missing when at idle in the water as well.

 

[David Martin]

Sorry to hear about the back order seems to be a problem right now.

 

[RobbieO]

The member dan bebe who has been messaging me said it should be tight. He is a yamaha tech. He changes them all the time. I know mine are worn out so I am going to change these before doing anything else. Unfortunately, these are on back-order with no ETA from Yamaha so it will be a while.

Do you have to pull the engine back to remove it?

 

[Ronnie]

Have you ruled out a failed coil(s)?