Overheating on both engines due to seagrass

[jaldmd]

i was on my way back in yesterday and as I was getting into the marina I heard the alarm for overheating. I was at the marina and some water was coming out of the pissers. The boat was only running for maybe five minutes.

I thought the boat was slow but was able to go about 38-40 on the water so figured there was some grass in the intake. I cleaned out the intake but only got some out of one. It helped a little.

Once I take the boat out and flush it engine temperature alarm still going off. There was still a bunch of sea grass in the intakes.

So, should I have let the engines cool off before flushing?

Any tips to clean out the intakes when on the water.

Any tips on how to prevent sea grass from getting in the intake, it was really packed in there.

Do you think I did any damage to the engines?

Thanks
Jeremy

 

[buckbuck]

Very unlikely you did any harm to the engines. They are quite robust.
Please reference the reverse move in the FAQ for clearing the jet pumps.
You do not need to let them cool before flushing provided it was only 5 minutes. Flushing is independent of the jet pump intake. You can prevent intermittent overheats while flushing by clamping the cooling hose on the upstream side of the Y fitting. That is, between the intake and the Y fitting. This forces all water to the engine and exhaust and not out the intake screen. You do want to remove the clamp for a time to back flush the screen as you may have grass clogging it.
I'll let the Florida boys chime in on tips for avoiding sea grass.

 

[jaldmd]

Where is the cooling water intake?

I assume I should make sure that is clear.

 

[buckbuck]

Look through the rear of the jet nozzle. It is a small plastic screen on the port side.

 

[jaldmd]

I'm learning about these systems so bear with me. It seems that is a silly place to put the cooling water intake. Can it be relocAted?

Or why is it there?

 

[2nazt]

It is one of the only spots where there is always water passing by and you wouldn't need an independent pump for each motor that would be another possible component to fail.

 

[Gym]

I'm learning about these systems so bear with me. It seems that is a silly place to put the cooling water intake. Can it be relocAted?

Or why is it there?

The cooling water intake is there because that is the pressure side of the impeller. The impeller pushes large volumes of water out of the rear of the nozzle to give us thrust while also pushing a small amount of water through the engine to keep it from overheating. Without this ingenious method they would have had to use a pump or rubber impeller, as other boats do, for cooling water.

The only thing you can do about sea grass is try to avoid it. If you run over a bunch of it you will suck it up. The reverse procedure may help but I find I have to pull the clean out plugs to get it all out.

 

[jaldmd]

So the sea grass allowed less water to pass by the cooling water intake therefore I overheated the engines?

Or was something else to blame

 

[2nazt]

Simple as that for a simple drive we have we get simple problems. I'd stick with seagrass and twigs instead of a lower drive unit hitting an underwater object and being a big issue.

 

[Julian]

Learn the reverse move trick : https://jetboaters.net/faq/i-keep-getting-stuff-stuck-in-the-pumps-any-tips-to-help-aka-the-reverse-trick.66/

Easiest way to clear weeds off your pumps....but if you let it build up too much you'll need to reach in there to clear them.

 

[Gym]

So the sea grass allowed less water to pass by the cooling water intake therefore I overheated the engines?

Or was something else to blame

Nope, you got it. We have an advantage over many other jet boat brands as we have clean out ports that allow us to clear most blockages while on the boat. As @Julian said, learn the reverse maneuver. It will alleviate many issues.

 

[jaldmd]

So I took the boat out just to make sure things are ok. All the sea grass is out of the grate and impeller.

It runs fine but I did notice the pissers are not flowing as much water as I remember before and the check engine alarms go off, not the overheat alarm just check engine. The alarms even go off when the engines aren't on and I'm just listening to the radio.

So I think the cooling water intakes are clogged. What do you think?

Also. Why does the check engine alarms go off even when the engines aren't on?

 

[buckbuck]

Did you flush the engines and use salt away?

 

[jaldmd]

I flushed the engines but didn't use salt away.

I also took off the rectangular covers for the cooling intake and there was nothing in there.

I'm about due for the 10 hour service so I'll just have them come out and check it.

 

[jaldmd]

Weird thing was that with engines off and just the radio on the check engine alarms would go off every 10 minutes or so. Water was coming out of the pee holes but seemed slightly light but maybe not.

 

[2nazt]

Water was coming out with engines off? I'm not familiar with new boats is there an alarm for anything else well engines off? Voltage depth etc? Or does it say engine overheat? Can you go into an alarm screen? Or reboot the system to maybe clear alarms.

 

[jaldmd]

When the engines were off the pee holes had no water coming out but the check engine alarms went off for both engines. When the engines were on water was coming out the pee holes and the check engine alarms would go off but not the overheat alarm. I would silence the arms and 5-10 minutes later the alarms would again go off. The boat would function properly though. I turned the engines off and was just listening to music and the check engine alarms would still go off. No water in the oil, engines didn't feel overheated.

But when I took the boat out and flushed the engines the alarms didn't go off. So maybe like the previous poster said it won't happen again.

I was thinking maybe there had to be a reset of the alarms or something if they went off. The service guy I spoke to didn't know the answer to that though.

I thought it was weird.

 

[jaldmd]

So I take it out for a spin today and guess what. No alarms. Drove it for about 20 minutes.

 

[itsdgm]

Sounds like you might have had low voltage while sitting and listening to the radio. But that's just a guess. My check engine light and alarm will only come on while the ignition switch is activated. Do you have to sit there with the ignition on in order to listen to the radio on your boat?

 

[jaldmd]

I believe so. The ignition key was on when the alarm went off and engines were off.

I doubt it was low battery. Seems to be fully charged and the boat only has 7 hours on it.

Hopefully it won't come back on like the previous poster