HELP, Motor is shutting down

[dscar4u]

Let me set the stage. I want some advice before I subject myself to someone (i.e.: the mechanic) with an agenda for this to be a bigger problem. I just purchased this boat 2 weeks ago. There previous owner said it had a new impeller and lower unit was serviced.
This is my first outboard and I am not used to seeing the engine pee.

I have had it out a few times and it has run great. Motor has very few hours and runs awesome and looks brand new. Yesterday I put on a whale tail to help the boat plane of quicker and boy did it ever. This boat shoots out of the hole now.
I had to remove the prop so it would not be in the way when I bolted on the whale tail.

Today I took the boat out to test it and it jumped out of the hole and was running fine for about 30 seconds and then my power fell off. It dropped to an idle and then I pulled the throttle back to N and then engaged it again and away we went but then it happened again.

I started to watch my gauges and the next time it happened I saw the rev limit come on and the Temp light. I pulled it out of the water and made sure I had the prop still on. Then I tried it again and this time I drove for about 2 minutes and it did it again.

I decided the whale tale was distorting the water flow and I took it off. I tried it again with out the wale tail and it did the same thing. This time though since it took a little longer to plane off I gave it more gas and as I was passing 4000 rpm it sounded like my prop was over spinning or like a clutch in a car slipping. I shut it down and lifted the motor. It looked good and so I cranked up and slowly brought it around and headed to the boat ramp at an idle. It took me about 5 minutes to get there and right when I got there the alarm went off and the temp light came on. I shut down and trolled in with the trolling motor.
Here are my questions:

1. I noticed the pee stream did not seam strong. How much pressure should it shoot the water out? Does this change with the rpm revved up.
2. Could I (by removing the prop) have made something slip? I put it back exactly like it was.
3. I put the boat in gear and I was hard to turn the prop. I could tell I was trying to compress the pistons and valves, but I could not see and prop slip. I really didn't know where to look though.

Thanks

 

[pamarine]

Answers

1. Yes, the strength of the stream is directly proportional to the RPM of the engine. As long as the water is coming out in a steady stream, there is sufficient water flow through the engine for proper cooling.

2. & 3. Based on your descriptions it does not sound like the problem is with the propeller. I would check the amount of oil in the lower unit, and also its color. Really want you are checking for is to make sure it is not cloudy, as this would indicate water in the oil. Also, you may want to look at the oil injection system. The amount of lubricating oil making it into the gasoline would also affect the operating temperature. From what you have described I would say there is more than likely water intrusio in the lower unit as a result of the mounting holes for the stabilizer fin not being fully sealed. Just an idea.

 

[dscar4u]

I forgot to mention than I also straightened the little fin on the bottom of the motor( I think its called a trim tab) last Saturday prior to taking it out. I seen it was crooked so I put it straight.
Then I went out last week and the boat was hard to turn. Later I found out, it is there to help me turn the boat. I loosened it and turned it at a 45 degree angle and now went out yesterday and now I am having this other problem. Maybe I don’t have it turned right but the boat sure is easy to turn. Could this be pushing water away from the prop? Or Causing a hole in the water, making the motor kind of spinning in air with no load.

Thanks

 

[fridaysoff]

You did not mention the year of the boat or motor so I don't know how long the boat sat around with little use before you bought it. Some times a motor with low hours on it may have a few problems from lack of use. The "new" impeller could have hardened and not be performing properly. You may have not put enough torqe on the prop when you put it back on. Several things could be happening,but with your limited knowledge(like mine) with the motor all of those bells and whistles are telling you its time to call in the mechanic before you blow your engine and spend thousands to get it fixed. A fair price to install a new impeller and check your water pump may only cost $100-200. The part of your post that worries me the most is the part where you were idling back to the ramp and the alarm and temp. light came on. That is the easiest way to blow an outboard engine . improper cooling. Call the mechanic; a good one. Good luck. I see at the bottom of your post that it is an 02 boat and motor.Also the tab is there for corrosion protection and to help your steering as you mentioned.It will not cause the water problems.
John D.

 

[glehav]

4u i am thinking like fridaysoff is, its the prop... sounds like it is slipping and over heating the motor when you put the prop back on did you see a key way on it and was a key in it and the prop does have to be torqued down to spec. the prop was the only thing you took off and put back on so thats what i would be looking at. the little thing you are calling at trim tab is to counter act the torque rotation of the prop so the motor want pull to one side all the time. if you put it back like it was you should be allright on that.. what size motor is it.and what year most older ones have a shear pin on the prop that will shear off when you hit something so it want damage the shaft could be that too... good luck

 

[dscar4u]

I am think the prop as well and i am going today to the prop shop to have them check it.

Thanks to all and i will let you guys know.

 

[BarryB]

If it ain't one thing...

Hi Discar,

If water is coming out of the pee hole, that indicates the impeller is working. And as PAMarine said, the stream is affected by RPM. However, if the motor has a thermostat, it may be stuck closed. This would not allow cooling water to circulate. You would have water coming out of the pee hole, but not cooling the rest of the motor.

Have you tried using a flush adapter on the motor?

When I flush my yamaha, the water out of the pee hole is cold, the water out of the exhaust vents, is hot.

Hope this helps.