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Yamaha Engine Behavior

Yes you get it in a tube. 3m 4200 is what I would use. You can get it at home depot or lowes.
I ordered this earlier today. Hopefully it will work. If not, I can try to get the 3M stuff that you mentioned.

 
I do not know for sure but I think it was last year. The last owner is a local guy that I know and he had the boat for 2 years. He put about 30 hours on it last year and had not used it this year. He did not change the plugs this season so I assume it was done last year.
Well, spark plugs and oil are cheap and things you can do if you want to keep the engines performing. Don't "assume" it's even ever been done. At least to start your own maintenance base-line.

Edit: added "spark" to these plugs because clean-out plugs are discussed as well
 
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Yes you get it in a tube. 3m 4200 is what I would use. You can get it at home depot or lowes.
I changed my plugs every season. We only put like 10 hours on it last season, i still changed the plugs.
 
A bit late to the party, but a few comments:
1) That twig was probably your issue--maybe your whole issue. Something like that exactly is what will cause cavitation. That is the type of thing for which you can look while on the water when you pull the cleanout plug. Reach back to the impeller and see if there is stuff like that in there trapped somewhere. I have had equal success at just running like that for a few minutes; sometimes it clears itself with a good high speed run (though it shakes a bit).
2) I make it a practice to always pull out the plugs when I come off the water. Lay them on the wet storage area and leave the wet storage sitting open (that way you cannot start the boat without going back there and putting them in--which only an idiot would do; ask me how I know).
3) I use gasket lube from my pool around the circumference of my cleanout plugs. You can get it on Amazon about $5 for a little tube that will last you plenty. Put some on 2-3x per season.
4) I agree you need a rebuild on the plugs now, though. They should go in and come out easily.
5) Yes, filling the gaps will help with cavitation. Basically any gap (including the ones circled) is suspect. You want it is smooth as possible from the outside of the boat into the impeller. I used just regular silicone caulk from the hardware store on mine. 4200 is fine, of course, but much stronger stuff (which is good, until you need to take something off--then it is more difficult...). The regular silicone caulk you can get in a squeeze tube or in the regular caulk tube.
6) Absolutely agree on the anode...
 
7) Another reason to change the plugs: If you leave them in for more than 2 seasons or so, regardless of hours on the engine, they can start to corrode into the block and become reaaaaallly difficult to get out. So regular changes are recommended. Right now I am at every other season, but I used to do it every season.
 
A bit late to the party, but a few comments:
1) That twig was probably your issue--maybe your whole issue. Something like that exactly is what will cause cavitation. That is the type of thing for which you can look while on the water when you pull the cleanout plug. Reach back to the impeller and see if there is stuff like that in there trapped somewhere. I have had equal success at just running like that for a few minutes; sometimes it clears itself with a good high speed run (though it shakes a bit).
2) I make it a practice to always pull out the plugs when I come off the water. Lay them on the wet storage area and leave the wet storage sitting open (that way you cannot start the boat without going back there and putting them in--which only an idiot would do; ask me how I know).
3) I use gasket lube from my pool around the circumference of my cleanout plugs. You can get it on Amazon about $5 for a little tube that will last you plenty. Put some on 2-3x per season.
4) I agree you need a rebuild on the plugs now, though. They should go in and come out easily.
5) Yes, filling the gaps will help with cavitation. Basically any gap (including the ones circled) is suspect. You want it is smooth as possible from the outside of the boat into the impeller. I used just regular silicone caulk from the hardware store on mine. 4200 is fine, of course, but much stronger stuff (which is good, until you need to take something off--then it is more difficult...). The regular silicone caulk you can get in a squeeze tube or in the regular caulk tube.
6) Absolutely agree on the anode...
@tdonoughue what is the gasket lube you use? I'm about to rebuild plugs, I have some wd-40 silicone I keep on the boat, but if there's something better that's still cheap I'm all ears.
 
Ok, so I am trying to find the rebuild kits so that I can have it done and use my boat again next weekend. So far I have had no luck because of shipping windows. I am still searching though.

I have the Yamaha spray silicone coming Wednesday so my plan is to try to clean out the clean out port walls and the plug(s). I am still not able to get the right side out though. I pulled as hard as I could and the right one felt like it budged a little but I do not know if that is the plug moving or the "T" handle moving somehow. Either way, I need to get it out. If I cannot get them rebuilt by this weekend, I am hoping that I can get it out and clean the port well enough and put silicone on it so that I can get them in/out for next weekend.

The stick that I found in the left impeller was not visible from the cleanout port. It was only visible from underneath and there was never any vibration that I could tell when we were driving the boat.

I ordered the marine silicon I mentioned above and I plan to run a bead of that all around the black metal plate on the bottom of the boat, as talked about above.

I hear what you guys are saying about the spark plugs. If I can find a good video for doing it on the engines in my boat and it is not very difficult to do, then I may at least check the plugs to see if they are black/charred. I am willing to change them as long as I am able to do it. This would definitely be a first, so I will be super careful and make sure that I have a good reference to watch.
 
On the spark plug topic, what spark plugs should I use for this boat? And do they need to be gapped/adjusted?
 
Ok, so I am trying to find the rebuild kits so that I can have it done and use my boat again next weekend. So far I have had no luck because of shipping windows. I am still searching though.

I have the Yamaha spray silicone coming Wednesday so my plan is to try to clean out the clean out port walls and the plug(s). I am still not able to get the right side out though. I pulled as hard as I could and the right one felt like it budged a little but I do not know if that is the plug moving or the "T" handle moving somehow. Either way, I need to get it out. If I cannot get them rebuilt by this weekend, I am hoping that I can get it out and clean the port well enough and put silicone on it so that I can get them in/out for next weekend.

The stick that I found in the left impeller was not visible from the cleanout port. It was only visible from underneath and there was never any vibration that I could tell when we were driving the boat.

I ordered the marine silicon I mentioned above and I plan to run a bead of that all around the black metal plate on the bottom of the boat, as talked about above.

I hear what you guys are saying about the spark plugs. If I can find a good video for doing it on the engines in my boat and it is not very difficult to do, then I may at least check the plugs to see if they are black/charred. I am willing to change them as long as I am able to do it. This would definitely be a first, so I will be super careful and make sure that I have a good reference to watch.
@djtech2k go to jetboatpilot.com, or give them a call. That's where I ordered my rebuilds, customer service is great and they can confirm and get them out quickly. They had them to me in two days, as long as they had them in stock.
 
On the plug: to get it out, you may need to wrap a short section of line around the T handle and around a 2x4. Put the end of the 2x4 over by the edge of wet storage or up by the cup holder and lift the other end of the 2x4 to get leverage. That is the easiest way I have seen. Others have used a floor jack to pull the thing out...

Meanwhile, if the silicone spray is what you have, better to use that now and get something on the plugs to be able to use the boat. You can order the other stuff and put it on when it comes in. Be aware that even with that you may not be able to get the stuck plug back in--swelling may be too much... Clean out the hole and the circumference of the plug and hopefully you can get it back in.

On the plugs, check the FAQ, where I think we have collected several of the ones for the several boats. I think yours is the same as mine, but I don't want to tell you wrong. NGK plugs are pre-gapped and ship with a cardboard protector on them. It is probably a good idea to check the gap, but a) I have never found one wrong yet (so I have stopped), and b) some say that moving the electrode to regap the plug weakens it and causes issues. So I just throw them in. I am probably a bad owner or something, but I have had no issue doing it that way for years.
 
Yes, you may need some more leverage on the stuck clean-out plug.

My manual lists NGK CR9EB. But most stores/web sites use part #6955. Pull one out to confirm.
 
Owner's manual is available at yamaha.com. That is your best source if there is some question or it is not listed on the FAQ.
 
Below are some notes I have taken regarding part numbers and links. Prices were from the off season. You should also be able to source the plugs at a local auto parts store...

replacing them requires a ratchet, I believe a 3-6 inch extension, a 10MM socket and a spark plug socket (can pick up at local auto parts store). Each plug will take you 1-2 minutes. Some suggest costing the threads on the plug with anti-seize. Don’t over torque when you replace.

process is remove retaining bolt (believe this is 10MM),pull boot out, remove old plug, thread new plug and reverse the process.


2012 SX210 Oil Change Kit
LUB-WTRCG-KT-00
$27.99 From Yahama x2

OEM Filter ~$15
YAMAHA 5GH-13440-20-00

K&N

Plugs NGK CR9EB x8
 
And lightly wipe some silicone grease on the plug insulator so the coil insulation is happy and not sticking.
 
I took the boat out yesterday. I noticed that the RPM's do briefly shoot up if I hit the throttle hard and then they fall into where I would expect them to be. I think both engines were doing this yesterday. I only felt the hesitation and surge 1 time on the left engine yesterday. It was in the first 5 mins and after that not again.

The left is at lower RPM but I think part of the problem is that it seems like the throttle seems to back down when I take my hand off of it, especially on the right engine. So if I move it to half throttle say, the right engine backs down when I take my hand off. I have to keep my hand on it to keep the throttle where I put it. When at full throttle, I have to keep pushing the right forward so it stays wide open. It does not back down a ton, but a few hundred rpm at least.

With 5 adults yesterday, I would say we maxed out at around 36-37mph. The conditions were mixed, like calm vs wake water and wind vs no wind.
 
A bit late to the party, but a few comments:
1) That twig was probably your issue--maybe your whole issue. Something like that exactly is what will cause cavitation. That is the type of thing for which you can look while on the water when you pull the cleanout plug. Reach back to the impeller and see if there is stuff like that in there trapped somewhere. I have had equal success at just running like that for a few minutes; sometimes it clears itself with a good high speed run (though it shakes a bit).
2) I make it a practice to always pull out the plugs when I come off the water. Lay them on the wet storage area and leave the wet storage sitting open (that way you cannot start the boat without going back there and putting them in--which only an idiot would do; ask me how I know).
3) I use gasket lube from my pool around the circumference of my cleanout plugs. You can get it on Amazon about $5 for a little tube that will last you plenty. Put some on 2-3x per season.
4) I agree you need a rebuild on the plugs now, though. They should go in and come out easily.
5) Yes, filling the gaps will help with cavitation. Basically any gap (including the ones circled) is suspect. You want it is smooth as possible from the outside of the boat into the impeller. I used just regular silicone caulk from the hardware store on mine. 4200 is fine, of course, but much stronger stuff (which is good, until you need to take something off--then it is more difficult...). The regular silicone caulk you can get in a squeeze tube or in the regular caulk tube.
6) Absolutely agree on the anode...

Everything he said.
 
@djtech2k , that certainly sounds like you are in the right neighborhood now. So a few more things, then:
a) The jump in RPM at hard throttle then settling down is likely cavitation (which is not good for your impellers). Basically, the impeller is spinning faster than the water can get in and get moving. As soon as it 'bites', you see the RPM's settle--that is the pump fully engaging.
b) The throttle falling off by itself--that is a very known issue. Search through the FAQ for throttle drop. There is a way to disassemble and squeeze something tighter in the throttle box there to help that. I have some throttle drop the same way, but it has not been bad enough for me to do the fix...
c) Your total speed with 5 adults on a 210SX might be a bit on the low side, but certainly within range. You may pick up some more speed with smoothed out intakes (did you do that part yet?). Basically anything (like those intake grate bolts) that causes inconsistency in the flow into the intake will rob speed and encourage cavitation. Get that all smooth and you may find not only do you have better out of the hole performance, but also better top speed.
d) You can check the throttle adjustment in the engine compartment (basically, some of the cables get out of adjustment so they don't push the engine all the way to full when the throttle is at full)--that is also where you fix any mismatch between the max on both engines (when they don't slide backward, that is). Pretty sure there is an FAQ on that, too. On my 240AR (same year), I usually max out at about 47 (though I have made it up to 52 once, probably with a tailwind, etc.).
 
@djtech2k , that certainly sounds like you are in the right neighborhood now. So a few more things, then:
a) The jump in RPM at hard throttle then settling down is likely cavitation (which is not good for your impellers). Basically, the impeller is spinning faster than the water can get in and get moving. As soon as it 'bites', you see the RPM's settle--that is the pump fully engaging.
b) The throttle falling off by itself--that is a very known issue. Search through the FAQ for throttle drop. There is a way to disassemble and squeeze something tighter in the throttle box there to help that. I have some throttle drop the same way, but it has not been bad enough for me to do the fix...
c) Your total speed with 5 adults on a 210SX might be a bit on the low side, but certainly within range. You may pick up some more speed with smoothed out intakes (did you do that part yet?). Basically anything (like those intake grate bolts) that causes inconsistency in the flow into the intake will rob speed and encourage cavitation. Get that all smooth and you may find not only do you have better out of the hole performance, but also better top speed.
d) You can check the throttle adjustment in the engine compartment (basically, some of the cables get out of adjustment so they don't push the engine all the way to full when the throttle is at full)--that is also where you fix any mismatch between the max on both engines (when they don't slide backward, that is). Pretty sure there is an FAQ on that, too. On my 240AR (same year), I usually max out at about 47 (though I have made it up to 52 once, probably with a tailwind, etc.).

Are you talking about the water intake area on the bottom of the boat? On mine, the metal has some stuff on it and the "finish" (not sure what it is) is partially on and off. Inside of the grates, there is that "channel" in the fiberglass that leads to the impellers. That are has all sort of stuff on there, mostly these little round crusty things. I can barely get any of my arm into that area. So is the grates and that channel in the fiberglass what you are talking about? If so, I'm not sure how I would get that smooth. Like I said, the finish on the grates is worn or half on/off. Unless the grates come off, I cannot reach inside that channel in the fiberglass. That is all not to mention that its under the boat lol. If I am in the right area, how would I get that smooth or whatever?

I thought it behaved better yesterday than the first time. The rpm's did jump but only seemed to happen when I get the throttle more aggressively. It did happen on both engines this times, at least I noticed it once at least.
 
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