2012 AR210 port motor overheating alarm

[Tuanhenryvu]

Glad to join the forum and thanks in advance for any help provided.

I purchased a used 2012 AR210 last week and during pre-purchase inspection, everything was fine. Previous owner had the spring start up service done to include Recharge Battery, Check all Cables, Change Spark Plugs, Put on Flush to burn off fogging oil and check for leaks. No issues.

2 days later I take it out to the river and 5 minutes in the water the port motor shows overheat and alarm goes off. I take it home, put it on the hose (good pressure) and same thing happens. The pee holes for both motors did not show signs of water coming out, both in the river and at home on the hose.

I've read a lot of posts and here is where I'm at currently.

1. I checked the clean out ports and water intake, no trash or debris.
2. I bought the YDS 1.33 version but wont get it for a few days.
3. I ordered a new thermostat but have not received it yet.
4. I bought a new set of NGK CR9EB spark plugs and will replace those in a couple days. What is the correct gap setting? Manual says .028-.031, but I've seen posts where people say .031-.035, which one is it?
5. I'm going to research the correct Yamaha replacement temperature sensor and if the items above don't fix the issues, Ill try replacing the temperature sensor.

Beyond these items listed, is there anything else I should consider troubleshooting before sending the boat to the shop for 3 weeks before it can be diagnosed? I hope the YDS will tell me what needs to be fixed.
Anyone have a YDS and wouldn't mind attaching a picture of where the cable plugs into the motor? I suspect it's the ECU?
I'm not new to boats but this is my first jet boat and the learning curve is steep.

Again, Thanks in advance for the help.

 

[David Martin]

THE Pee holes are a good indicator of a blockage somewhere. I new to Yamaha jet but I have lived in Florida for the last 6 years and have seen and helped my neighbors fix many outboards not pee/streaming water so far it always been a stuck thermostat. With your thermostats housing OFF look into passages for a build up of debris calcium ect.......... I feel you are starting at the proper place THERMOSTATS.

On a side note my water temp exiting my exhaust and a through hull fitting (next to my jet drive) is 135 to 140 degrees with a vary vary good amount of water exiting both these ports.............if you have a low amount of water coming out these ports, due to some kind of blockage it will be hotter than the temps mine is putting out. Get yourself a infrared temp gun they come in handy. I have never got a temp on the block,exhaust,heads over 140 on my temp gun after running 3 hours around Charlotte bay in Florida.

Good luck and hope the helps

 

[Tuanhenryvu]

THE Pee holes are a good indicator of a blockage somewhere. I new to Yamaha jet but I have lived in Florida for the last 6 years and have seen and helped my neighbors fix many outboards not pee/streaming water so far it always been a stuck thermostat. With your thermostats housing OFF look into passages for a build up of debris calcium ect.......... I feel you are starting at the proper place THERMOSTATS.

On a side note my water temp exiting my exhaust and a through hull fitting (next to my jet drive) is 135 to 140 degrees with a vary vary good amount of water exiting both these ports.............if you have a low amount of water coming out these ports, due to some kind of blockage it will be hotter than the temps mine is putting out. Get yourself a infrared temp gun they come in handy. I have never got a temp on the block,exhaust,heads over 140 on my temp gun after running 3 hours around Charlotte bay in Florida.

Good luck and hope the helps

Thanks David. I talked to the previous owner and he has never changed the thermostats so even if that’s not the root cause it’s probably best to change them anyway.

 

[BrentEB]

Thanks David. I talked to the previous owner and he has never changed the thermostats so even if that’s not the root cause it’s probably best to change them anyway.

It's a good idea to pull & check the thermostats anyway - some debris could restrict flow.

 

[WREKS]

Welcome @Tuanhenryvu What is your general location? Did you test it on the water? If the deal is not totally sealed, I would back out. Overheating motors often require removing the engine, then removing the cylinder head, then cleaning out the cylinder water jackets to remedy the problem. Most of the time, flushing will not help. YDS may have some record of overheating. There may be an access cover to get to the connecters for YDS in the engine bay.

 

[Tuanhenryvu]

Welcome @Tuanhenryvu What is your general location? Did you test it on the water? If the deal is not totally sealed, I would back out. Overheating motors often require removing the engine, then removing the cylinder head, then cleaning out the cylinder water jackets to remedy the problem. Most of the time, flushing will not help. YDS may have some record of overheating. There may be an access cover to get to the connecters for YDS in the engine bay.

Wreks,
I purchased the bought after a sea and land trial. Im Hoping your wrong and I don’t need to rip the engine apart to fix it. I’m in Williamsburg, VA.

 

[Tuanhenryvu]

It's a good idea to pull & check the thermostats anyway - some debris could restrict flow.

Brent,

I’m going to change plugs, replace thermostats and hook up YDS first.Hoping it’s a simple fix but if it’s more serious as WREKS suggested I’m not sure what I’ll do.

 

[WREKS]

When you remove the thermostat, before you clean it up or toss it, please post a picture of it. If it is covered with white/ brown jelly like substance, that can indicate bio-fouling in the cylinder water jackets.

The cooling systems have to be dried out to prevent a microbial build up that needs water to survive. A wet cooling system after flushing provides just that. I have been running the motors about 1½ minutes without water from time to time after an outing to dry out the cooling systems. That prevents overheating. I hope that is not the case with you. Once the build up occurs, I have not been able to flush it out.

 

[Tuanhenryvu]

When you remove the thermostat, before you clean it up or toss it, please post a picture of it. If it is covered with white/ brown jelly like substance, that can indicate bio-fouling in the cylinder water jackets.

The cooling systems have to be dried out to prevent a microbial build up that needs water to survive. A wet cooling system after flushing provides just that. I have been running the motors about 1½ minutes without water from time to time after an outing to dry out the cooling systems. That prevents overheating. I hope that is not the case with you. Once the build up occurs, I have not been able to flush it out.

Thank you Wreks. I’ll post a picture of the condition once I’m done. I’m also going to change the plugs as well. Looking at the diagram it appears these motors have 3 temperature sensors. I need to research they more. I appreciate the insight.

 

[Dfred]

(This is 2009 AR210, should be same for 2012)
The YDS plug is the square head/3-prong grey one. It is tucked up in the cable bundle under the back edge of the engine compartment, and almost hidden behind the vent ductwork on the starboard/right engine. There may be a plug cap dangling from it.
The pic above is the port/left side #1 engine.
The pic below is the starboard/right side #2.
- Lay some cardboard/padding on top of the engine to get comfortable reaching out over there with both hands to disconnect the feed and connect the YDS USB cable.
- Read up on the instructions to get the windows computer COM port setting correct for COM1
- To access the engine diagnostics- start YDS, and simply bump the starter key on, No need to run the engine while connected to get the reports and sensor tests from the ECM. You can run the engine and get live diagnostics also.

 

[WREKS]

@Tuanhenryvu The thermostat may be ok. Here is how to check

 

[WREKS]

@Tuanhenryvu The temperature sensor that is probably in play here is the Engine Thermoswitch. It is located under the Exhaust Manifold by Cylinder #1. On the 2007 SX230 HO it all but impossible to remove to test without removing the engine.

If you use an Infrared temp sensor(Harbor Freight, $29) and shine below the exhaust manifolds while running on the hose, and find one or more cylinders running hot (200 degrees +), you have found the problem.

 

[Tuanhenryvu]

@Tuanhenryvu The temperature sensor that is probably in play here is the Engine Thermoswitch. It is located under the Exhaust Manifold by Cylinder #1. On the 2007 SX230 HO it all but impossible to remove to test without removing the engine.

If you use an Infrared temp sensor(Harbor Freight, $29) and shine below the exhaust manifolds while running on the hose, and find one or more cylinders running hot (200 degrees +), you have found the problem.

Thanks Wrek, the problem being the tmep sensor?

 

[Tuanhenryvu]

View attachment 151317
(This is 2009 AR210, should be same for 2012)
The YDS plug is the square head/3-prong grey one. It is tucked up in the cable bundle under the back edge of the engine compartment, and almost hidden behind the vent ductwork on the starboard/right engine. There may be a plug cap dangling from it.
The pic above is the port/left side #1 engine.
The pic below is the starboard/right side #2. View attachment 151318
- Lay some cardboard/padding on top of the engine to get comfortable reaching out over there with both hands to disconnect the feed and connect the YDS USB cable.
- Read up on the instructions to get the windows computer COM port setting correct for COM1
- To access the engine diagnostics- start YDS, and simply bump the starter key on, No need to run the engine while connected to get the reports and sensor tests from the ECM. You can run the engine and get live diagnostics also.

Thanks DRED. Once I get the YDS, I'm going to figure it out. Thanks again.

 

[WREKS]

@Tubular252 No! The problem is probably not the temperature sensor. It may be an internal blockage.

 

[Tuanhenryvu]

WREKS,

Sounds like your pretty confident its blockage. Have you experienced this problem before?

 

[RightStuff]

I take it home, put it on the hose (good pressure) and same thing happens. The pee holes for both motors did not show signs of water coming out, both in the river and at home on the hose.

When on the hose you might not see water come out the side of the boat, it takes a bit throttling up to make it come out and even them it's usually just a trickle. Not saying that you don't have a blockage in your cooling lines, but that's what I see when I run mine on the hose. Usually north of 3000 RPM for a bit of time is when I start to see water come out. It does pour out from around the jet pumps without throttling up. Anyway, just wanted to chime in with what is "normal" when running on the hose.

If you have an error message of an overheat, you might not get much more info from YDS than an overheat message in the software. It might tell you some more info that leads you to something else being amiss though so still worth having for future diagnostics. There is a way to get error messages from the tach screen, see 7-34 in the manual for instructions.

One other thing to check is the inlet strainer on the pump housing, see pg. 3-10 in the service manual. Sounds like you have the manual, if not let me know and I can post a pic of it.

As for plug gap, I have always shot for .3 and haven't had any issues.

 

[Chip F.]

At the beginning of the season I had my port engine temp alarm in and would not clear . For some reason I remember something about trying to start and stop that engine 5 times - I did it fast and the alarm cleared . worth a try .

 

[Tuanhenryvu]

Rightstuff,

I'm hoping the YDS will show me some historical data prior to last week when I bought the boat. This will help me understand if this is a new or existing issue.
I have the owners manual not the service manual. Anyone have a copy of the 2012 AR210 service manual on .pdf they are willing to share?

Thanks for the plug gap setting. I was going to set them at .030

 

[Tuanhenryvu]

At the beginning of the season I had my port engine temp alarm in and would not clear . For some reason I remember something about trying to start and stop that engine 5 times - I did it fast and the alarm cleared . worth a try .

I was also told to disconnect the battery as well. So turn on the motor and turn it off 5 times quickly? Ill try it but now its starting to sound alot like vudoo magic.lol