65 HP Evinrude Jumping/Skipping???

[jameshamlet88]

I have a 1972 65 HP evinrude (not sure of the model number). When the motor is out of the water and being flushed with water, the motor runs in forward fine, but when I put the boat in the water and went forward, it started jumping/skipping a little at low speeds, and when I gave it more gas, it started jumping/skipping more rapidly, and then at full throttle, it just stopped going. The side mount control's neutral and reverse is not working (wiring problem) and it has defaulted to forward. Anyone have any clue what this could be?

 

[F_R]

Re: 65 HP Evinrude Jumping/Skipping???

Sure. Worn out dog and gear in lower unit. Very badly worn out. Actually, it is sort of unusual on those because of the way they are made and work. Maybe instead of it being that, the shifter piston might be stuck in the oil pump and just barely engaging the dog/gear. Now that I think about it, that seems more likely.

 

[tashasdaddy]

Re: 65 HP Evinrude Jumping/Skipping???

if the lower unit has the wrong lube in it can cause this also, here's an explanation, of the working of your lower unit.
http://forums.iboats.com/showthread.php?t=166519

 

[jameshamlet88]

Re: 65 HP Evinrude Jumping/Skipping???

Why does it not jump/skip when the motor is out of the water (in forward), and only being flushed? Also, how do you add/check/replace the fluid in the lower unit, and what kind should I use?

 

[F_R]

Re: 65 HP Evinrude Jumping/Skipping???

Simple. There is no load on it when on the trailer. Put some horsepower against the resistance of the water and it jumps.

To change the fluid, remove both large slotted screws on the gearcase and let it drain out. Use only OMC/BRP Premium Blend Gearcase oil. Previously known as Type C. Fill from the bottom hole till it comes out the top. Then, keeping the filler in the hole, install the top screw. That will air lock it to keep the oil from gushing out when you remove the filler and install the lower plug. Put new gaskets on the plugs while you are at it. If filling from squeeze tubes you will need to change tubes in mid stream. You can also buy the oil in larger containers with a little pump to make it a whole lot easier.

 

[BoatBuoy]

Re: 65 HP Evinrude Jumping/Skipping???

You said "and then at full throttle, it just stopped going". Do you mean the engine quit?

 

[jameshamlet88]

Re: 65 HP Evinrude Jumping/Skipping???

No, the motor didn't quit, but it just revved up really high and didn't go anywhere, like it was in neutral...?

 

[jameshamlet88]

Re: 65 HP Evinrude Jumping/Skipping???

Also, this is a link to the gear lube on this site, is it the correct kind of lube?

http://iboats.com/Lubrimatic_Type_C...id.217317--list_time.1177072727--view_id.2371

 

[ezeke]

Re: 65 HP Evinrude Jumping/Skipping???

[FONT=Helvetica, sans-serif]You may also have a spun prop with the same indications. I would think you would hear some racket if the clutch dog were popping in and [/FONT][FONT=Helvetica, sans-serif]out. [/FONT]

 

[jameshamlet88]

Re: 65 HP Evinrude Jumping/Skipping???

Where is the dog/gear located, and how would I go about getting to it to see the condition of it?

 

[ezeke]

Re: 65 HP Evinrude Jumping/Skipping???

The clutch dog is located between the forward and reverse gears on the propeller shaft. You need to disassemble the gearcase to work with it. In most instances that would require at least a model specific service manual.

The parts manual for your motor will include the gearcase diagram, which will assist in visualizing the parts.

http://epc.brp.com/default.aspx?brands=ej&lang=e



​

 

[F_R]

Re: 65 HP Evinrude Jumping/Skipping???

Yes that is the correct oil, Lubrimatic version. The suggestions about it being the prop hub are very valid. My prior comments were based on you saying it was "jumping and skipping" If it is just slipping without "jumping" it very well might be the prop.

 

[jameshamlet88]

Re: 65 HP Evinrude Jumping/Skipping???

what's the difference between jumping and slipping? It seems like the motor is jerking, and moving, and it makes the boat shake... is that jumping or slipping?

 

[F_R]

Re: 65 HP Evinrude Jumping/Skipping???

I interpret that as jumping. Slipping is smooth, like spinning your wheels on the ice. Ain't the English language fun?

 

[ezeke]

Re: 65 HP Evinrude Jumping/Skipping???

The hub of the propeller has an inner and outer part separated by a rubber grommet, which can be seen most easily from the rear of the propeller when removed.

Over time the exhaust heat, stress and age can cause the rubber grommet to lose the grip on the propeller and slip.

If you use a permanent marker or some device to scratch a line from the outer edge of the propeller hub and across the shaft, you can determine if the propeller is slipping the next time you run it.​

 

[jameshamlet88]

Re: 65 HP Evinrude Jumping/Skipping???

I changed the fluid in the gear case, and that didn't work. However, when I took the boat out yesterday, it was still jerking, but it seemed like it was overheating and getting really hot and smoking. It eventually cut off, and I would have to wait for it to cool down before it would run again. Any ideas??

 

[F_R]

Re: 65 HP Evinrude Jumping/Skipping???

Aw heck. Now you got more troubles. Obviously, the water pump isn't working. The fact that you let it get so hot that it quit is bad news. You may (probably) have at least some engine damage from that.

OK, lets make a dangerous assumption. The water pump is driven by the drive shaft between the powerhead and lower unit. So is the rest of the lower unit. What if the shaft were broken or the splines stripped? Just guessing.

It's time to stop guessing. You really need to get into that thing before any more damage is done. Quit running it till you have a definite answer. And the powerhead checked out for overheat damage. Good luck, you are going to need it.