Engine over heat after tow rope caught

[Jmpicking]

I swapped one of the thermo switches and nothing changed. Switched it back. And now the good engine is saying check engine.........wtf is going on

 

[Cambo]

So now both engines are throwing a code at the same time? Sounds like an electrical gremlin corroded sensor plug when you swapped it maybe some corrosion was left behind ? How did the plug on the harness look?
Are you the original owner ? Is it a saltwater boat ?

 

[Cambo]

Good info in this link

https://jetboaters.net/threads/bad-thermosensor-intermittent-overheat.8032/

I like the added trail tech temp gauge . Let me know if the sheared bolt came out with my recommendation to drill and use the Allen key

 

[Jmpicking]

So now both engines are throwing a code at the same time? Sounds like an electrical gremlin corroded sensor plug when you swapped it maybe some corrosion was left behind ? How did the plug on the harness look?
Are you the original owner ? Is it a saltwater boat ?

I’m not the original owner it is in saltwater .the plug looked real clean that I swapped. So the good engine now says check engine and the bad engine still says overheat

 

[Jmpicking]

Is there a Water pump on a Yamaha ar 210. Was told it could be that it went bad, or that it’s bent cylinder valves. Any thoughts?

 

[Cobra Jet Steering LLC]

Nope it is your jet pump as discussed the holes on the left side where the square part with the hoses coming out is where the water to the engine comes from. I think you have sensor and electrical issues . Yamaha had a bad reputation in the past for bad heat sensors not so much recently. people would add resistors to the sensor pickup connection to fool the computer into thinking the sensor was still attached. Once you have issues with those it's never going to stop without fixing it.

 

[Jmpicking]

Nope it is your jet pump as discussed the holes on the left side where the square part with the hoses coming out is where the water to the engine comes from. I think you have sensor and electrical issues . Yamaha had a bad reputation in the past for bad heat sensors not so much recently. people would add resistors to the sensor pickup connection to fool the computer into thinking the sensor was still attached. Once you have issues with those it's never going to stop without fixing it.

So I swapped the one sensor but I could quite reach the other sensors without taking off a ton of stuff . And after swapping the last sensor the check engine light went off on the non overheating engine, so I swapped it back and it still it saying check engine, and the the throttle is jammed ! So I have no clue what happened during that swap.

 

[Cambo]

Can you send pictures of your jet pumps just curios to see how they look . The throttle jam could be the shift gate cable is corroded

 

[Jmpicking]

I only took off the jet pump of the engine that’s been overheating not the one with the throttle stuck, because that only happened after swapping thermoswitches

 

[Cobra Jet Steering LLC]

hmm did you leave something inside the engine compartment that is locking up the throttle or is there something locking the reverse bucket just guessing

 

[Jmpicking]

hmm did you leave something inside the engine compartment that is locking up the throttle or is there something locking the reverse bucket just guessing

I have no idea, I really didn’t touch anything on that engine, I’ll look closer when I get home, im99% sure all I touched was the thermoswitch and swapped it . But I swapped it back, so now it’s the original one and throttle still locked and check engine is still on .. doesn’t make sense

 

[Cobra Jet Steering LLC]

Most likely the stuck throttle is something that is in the way of the reverse bucket.

 

[Jmpicking]

Most likely the stuck throttle is something that is in the way of the reverse bucket.

Where’s that located I don’t see it on parts breakdown

 

[Cobra Jet Steering LLC]

It's on the nozzle the part that moves up and down when you put the boat in forward or reverse if it gets stuck the throttle can become inoperable

 

[Jmpicking]

Yeah but I wasn’t messing with that back there at all, I was only in the engine hatch

 

[tdonoughue]

Do our check engine lights say on until cleared?

Hypothesis: swapping the (allegedly) bad sensor to the good engine caused the check engine light (masked on the bad engine because it read it as overheat in conjunction maybe with the other bad sensor?). Now un-swapped, the engine is still throwing the code because it is not been cleared via YDS.

Further hypothesis: both sensors are bad on the overheating engine.

Do you have or do you have access to a YDS? I don't see a location on your profile, but if you fill that in, there may be a nearby member who can lend you one.

 

[Jmpicking]

So update... my mechanic worked on it for 7 hours today.
He replaced the sensors, computer, reset codes using the software, took the manifold off, and other things, ran it on the water, still says overheat.
He told me the engine is not actually overheating it just thinks it is, but he can’t figure out why since he replaced everything having to do with it.
He says it’s got demons in it..
Any thoughts?

 

[Scottie]

I don't have any good suggestions as to what's causing the overheat alarm, but those findings certainly line up with the temps you were measuring yourself, so I would trust that assessment. At least it's not actually overheating, for whatever that's worth.

 

[Jmpicking]

Yeah he said it’s all electrical but he has no clue how it’s electrical when he replaced all the sensors

 

[Cobra Jet Steering LLC]

when in doubt hit every stinking ground wire you can find and check them for continuity and be sure it is making good contact as well as clean any wire connectors and spray them with silicon just in case water is shorting out a plug happens to me occasionally spray silicon on all the wire connectors it will fix it instantly.