My boat is giving me headache

[RyanTexas]

Hi guys, I recently joined to look for help in my Yamaha jet boat.

Its model is: 2008 Yamaha SX210

The problems:
The overheat warning light on the port side engine is on, when putting it in the lake at idle speed for 10 min, the pissing holes pumped hot air, but only droplets of hot water came out. While it is still tied to the dock, I gave it some gas to 4000rpm to see if more water coming out of pissing holes, they remain the same, only droplets came out. The weird part is the boat didn't move at all, at least the rope has to be stretched at one end.

I towed it back home and inspected:
+ both jet drives ran just fine, they spin according to the gas I put in.
+ Intake water screen and hose from screen to the 1st T connector, no clog at all.
+ the water hose feeding to the pissing holes, also not clogging at all, I blew both of them it using my mouth.
+ When running the port engine off the flush hose, it ran fine, no overheat warning came on, but the pissing holes also have no water coming out.
+ Oil also half changed to the correct level, when the engines are leveled.

Can someone kindly show me a direction to resolve this? Mechanics are busy and they won't get to my boat for a couple of months.

Thank you,

Ryan

 

[djetok]

Hi guys, I recently joined to look for help in my Yamaha jet boat.

Its model is: 2008 Yamaha SX210

The problems:
The overheat warning light on the port side engine is on, when putting it in the lake at idle speed for 10 min, the pissing holes pumped hot air, but only droplets of hot water came out. While it is still tied to the dock, I gave it some gas to 4000rpm to see if more water coming out of pissing holes, they remain the same, only droplets came out. The weird part is the boat didn't move at all, at least the rope has to be stretched at one end.

I towed it back home and inspected:
+ both jet drives ran just fine, they spin according to the gas I put in.
+ Intake water screen and hose from screen to the 1st T connector, no clog at all.
+ the water hose feeding to the pissing holes, also not clogging at all, I blew both of them it using my mouth.
+ When running the port engine off the flush hose, it ran fine, no overheat warning came on, but the pissing holes also have no water coming out.
+ Oil also half changed to the correct level, when the engines are leveled.

Can someone kindly show me a direction to resolve this? Mechanics are busy and they won't get to my boat for a couple of months.

Thank you,

Ryan

Is the hose clogged?

Do you store it outside where a mud dobber made a home.

You can run some weed trimmer line in the pisser to break it up.

Oil cooler leak?

 

[tdonoughue]

No, this does not sound like a clog. If there is hot air coming out, you must have a hole in the system somewhere letting air in (and destroying the suction for the water).

First I would work backwards from the Y fitting toward the engine and look for breaks in the line. With all that hot air and a little spittle, I am betting you have a hose off or a big split in a hose somewhere or something like that.

I thought of recommending a hose to the pisser to find the leak, but on second thought that might flow water backwards into the engine (which is a bad thing--good way to hydrolock your engine).

If you run your engine on the hose, does it overheat still?

 

[RyanTexas]

When engines are running, I saw only white smoke, I don't think oil is leaking. When I pumped old oil out, it was not milky so I don't think water leaked into oil.

I used air compressor to blow through the pissers from the engine, they are clean.

 

[tdonoughue]

From where was the white smoke? There should be no white smoke. White smoke usually is water vapor--water is leaking out onto something hot (causing steam) and letting in air (which is the hot air you are feeling from the pissers).

 

[RyanTexas]

No, this does not sound like a clog. If there is hot air coming out, you must have a hole in the system somewhere letting air in (and destroying the suction for the water).

First I would work backwards from the Y fitting toward the engine and look for breaks in the line. With all that hot air and a little spittle, I am betting you have a hose off or a big split in a hose somewhere or something like that.

I thought of recommending a hose to the pisser to find the leak, but on second thought that might flow water backwards into the engine (which is a bad thing--good way to hydrolock your engine).

If you run your engine on the hose, does it overheat still?

When running the engine off the flush water hose, no overheated. I had the engine running at 6k rpm for 15min, no warning light came on.

 

[tdonoughue]

Ok, good clue. So your issue is between the Y for the hose and the inlet at the jet. Look for a slice in a hose or a hose off.

 

[RyanTexas]

From where was the white smoke? There should be no white smoke. White smoke usually is water vapor--water is leaking out onto something hot (causing steam) and letting in air (which is the hot air you are feeling from the pissers).

Your logics is very logical. Where can I buy the hose and cut them to size to replace the whole water line?

 

[tdonoughue]

I like my logics logical.

Find your leak first. Then I think any auto parts store should have rubber hose in bulk that should do the trick. But you will need to find the leak to find the right size...

 

[RyanTexas]

I like my logics logical.

Find your leak first. Then I think any auto parts store should have rubber hose in bulk that should do the trick. But you will need to find the leak to find the right size...

I ran it for 10min with the water hose, I found the steam came off was due to hot water pouring out from a big hole, upper-right, right above the jet nozzle. Another weird thing is now the temp light came on, it didn't before when the engine was running off the water hose.

 

[tdonoughue]

Ok, so have a look at https://jetboaters.net/threads/2008-sx230ho-cooling.22340/. I think where you are describing is the normal exit for the cooling water. So if you are getting hot water out of there, that is as it should be (and steam there would be ok).

The temp light coming on with the hose means we can't narrow the problem as previously suggested. But I am still thinking a hole somewhere if you have air coming out of the cooling system anywhere, basically (pissers or out the back).

 

[tdonoughue]

@zipper --this is close to your year, right? Thoughts?

 

[Scottintexas]

Watch bucks video in faq about how the cooling water flows and diagnose it from there
If no overheat, maybe the intake screen or hose is partially blocked

 

[tdonoughue]

Video is a good idea; I just could not find it. FAQ--of course... duh.

He has overheat. And air coming out of the pissers. So I am thinking there must be a hole/hose off somewhere...

 

[Canuckjetboater]

When engines are running, I saw only white smoke, I don't think oil is leaking. When I pumped old oil out, it was not milky so I don't think water leaked into oil.

I used air compressor to blow through the pissers from the engine, they are clean.

.....white smoke is NOT good. Respectfully you need to troubleshoot or provide water to the engine while troubleshooting before you scorch your engine.

 

[Scottintexas]

 

[AZMark]

Hi guys, I recently joined to look for help in my Yamaha jet boat.

Its model is: 2008 Yamaha SX210

The problems:
The overheat warning light on the port side engine is on, when putting it in the lake at idle speed for 10 min, the pissing holes pumped hot air, but only droplets of hot water came out. While it is still tied to the dock, I gave it some gas to 4000rpm to see if more water coming out of pissing holes, they remain the same, only droplets came out. The weird part is the boat didn't move at all, at least the rope has to be stretched at one end.

I towed it back home and inspected:
+ both jet drives ran just fine, they spin according to the gas I put in.
+ Intake water screen and hose from screen to the 1st T connector, no clog at all.
+ the water hose feeding to the pissing holes, also not clogging at all, I blew both of them it using my mouth.
+ When running the port engine off the flush hose, it ran fine, no overheat warning came on, but the pissing holes also have no water coming out.
+ Oil also half changed to the correct level, when the engines are leveled.

Can someone kindly show me a direction to resolve this? Mechanics are busy and they won't get to my boat for a couple of months.

Thank you,

Ryan

Are your clean out plugs in? Why would the boat not move at 4000rpm?

 

[AZMark]

I ask about the plugs because the system needs pressure to force water up the lines. There is no traditional impeller that would suck water through.
I don’t think pissers do much on a hose, most of it goes out the back so I wouldn’t get too caught up on that.

 

[Babin Farms]

@WREKS has a lot of info on the cooling system, maybe he'll chime in.

 

[zipper]

When running the engine off the flush water hose, no overheated. I had the engine running at 6k rpm for 15min, no warning light came on.

I ran it for 10min with the water hose, I found the steam came off was due to hot water pouring out from a big hole, upper-right, right above the jet nozzle. Another weird thing is now the temp light came on, it didn't before when the engine was running off the water hose.

Surprised you did not trip a temp. alarm when you ran the motor at 6k rpm's for 15 mins. Your water pressure, on the hose, must be pretty good. The "big hole" is the exhaust outlet. I would expect to see water vapor there, STEAM is invisible, especially after running for 10-15 mins. There is also an outlet for the thermostats back there on the transom plate unless you do not have the HO MR-1's. https://jetboaters.net/threads/transom-plate.8756/#post-150720 . The thermostats could need servicing. https://jetboaters.net/threads/mr-1-thermostat.21899/#post-372769

A couple of days ago on the Lake, it surprised me at how many RPM's it took to see a stream, not dribble, of water come from the pissers. It was up around 6k rpms.