stalling honda 4-stroke 90hp above 20 knots

[Vincent Manrique]

When running my Honda 4 stroke on my Stieger craft 21ft,I am having the problem of the alarm going off and engine cutting out. This happens once the engine is hot. Once I let it rest a few minutes it starts back up and runs for another 15 minutes before happening again. I changed the oil and oil filter, fuel line and fuel filter, and the impaller. It's still happening. Any suggestions on what to do next? Something is making the overheating alarm shut down the motor.

 

[Drowned Rat]

Re: stalling honda 4-stroke 90hp above 20 knots

Did you check for a clogged or bad thermostat?

 

[hondon]

Re: stalling honda 4-stroke 90hp above 20 knots

When you changed out that impeller ,how did every thing else look down there?No melted housings or bases?No plates or cups grooved ?Did we blow a little air back through the water tube to see what kind of flow we have there and what kind of debris got blown out?There have been updates to that impeller and where you are may indicate you are using an outdated product. Look carefully at the impeller near where it attaches to the plastic part nearest the driveshaft.In the rubber at this glued union you will see VERY TINY letters ,either A,AA,or AAA,in tiny print.You need to see AAA.

 

[Vincent Manrique]

Re: stalling honda 4-stroke 90hp above 20 knots

I should correct that after it stalls I only have to wait a few seconds before restarting it. And then it runs for 15-20 min before doing the same thing. I changed my thermostat a couple years ago but will look at this. I also did not know about the impeller letters, BUT note that when changing it, there was no damage to the impeller or the general area. Is it worth opening it up again to look at the letters? I utilized the kit that I bought two years ago. There does not appear to be any blockage in the circuit. Thank you for your suggestions.

 

[hondon]

Re: stalling honda 4-stroke 90hp above 20 knots

It might be worth a look.That failure involves a cracked impeller liner that allows the impeller to spin on the driveshaft when ever it wants to.It is really hard to see unless you are looking for it.Look for a tiny vertical line anywhere on the inside of the impeller,then flex it and beat it up and see if you have any slipage between the impeller vanes and the hub.

 

[Vincent Manrique]

Re: stalling honda 4-stroke 90hp above 20 knots

Hello.<br /><br />I checked the thermostat. It was full of debris. Now my next question is: what is the most effective way to flush the inside of the engine without damaging the inside...the motor is a 90 horse power 4 stroke, year 97.<br />Thanks for everything....<br />Vincent

 

[jim dozier]

Re: stalling honda 4-stroke 90hp above 20 knots

Pull the lower unit off, put a bucket underneath so you can see what comes out and backflush the system through the thermostat cover with a garden hose. Depending on the shape of the thermostat housing you may have to stuff a rag or something around the head of the garden hose to effect some kind of a seal. You can also clamp a garden hose to the water tube pickup (where is joins the water pump) and flush the engine and check the quality of flow.

 

[Hawaiian]

Re: stalling honda 4-stroke 90hp above 20 knots

Vincente, how did the thermostat get clogged? Do you have a screen filter covering your intake?