Water from exhaust?

[amishboy]

1998 Evinrude 50hp. I have water coming from the upper exhaust at idle and low speed and don't remember if this is normal or not? Water from tell tale is a steady stream an old man can be jealous of... Also, engine seems to be shaking more. Prop has some slight bends in the blades. Could this be it or do I have a bigger problem?

 

[amishboy]

...this is on a 24' pontoon.

 

[daman4469]

Shaking could be caused by the blades, but many other things as well. I doubt it's related to your water concern. Is it only when idling or when in gear and at speed?
I had a 1996 evidrude SPL88 and it had the exhaust st the prop....small holes at base of motor were the 'upper exhaust'....water came out of those as well as the squirter.

 

[amishboy]

Shaking is more prominent at lower speeds.

 

[F_R]

Most likely the bent prop blades. Or it's running on one cylinder. How is it under power?

 

[amishboy]

It does seem to smooth out with more speed.

 

[amishboy]

Tried again tonight. Shakes up to about 1900 rpm and smooths out at 2100, but the speed at 2100 is where it used to be at about 1500 with only me on board. Runs good to about 3200, beyond that, without touching the throttle, it will run up by itself to about 4000 with no additional speed. When I go max on the throttle, it will go as high as 6k rpm. I don't let it set there. I'm not quite sure how a bad prop might cause the rpm to jump without throttle.

 

[daman4469]

You may have some serious prop slip and cavitation due to the blades not being in line.

Running with a bent prop is bad for business....not only is it inefficient, but can cause cavitation, shaft imbalance, and unresponsive steering. It is hard on your lower unit and everything that ties in to it. I'd get it replaced before running again.

 

[jakedaawg]

Tried again tonight. Shakes up to about 1900 rpm and smooths out at 2100, but the speed at 2100 is where it used to be at about 1500 with only me on board. Runs good to about 3200, beyond that, without touching the throttle, it will run up by itself to about 4000 with no additional speed. When I go max on the throttle, it will go as high as 6k rpm. I don't let it set there. I'm not quite sure how a bad prop might cause the rpm to jump without throttle.

Could you clarify here. If you are saying the engine goes from 3200 to 4000 without additional boat speed or are you saying it goes higher in revs without moving throttle?

 

[jakedaawg]

Why don't you post a pic of the prop. If it's just nicked up a bit it's not a big deal really. If you blades that are bent you should send it to a prop shop for repair. A spun hub can be checked by making a reference mark on the inner and outer hubs then run boat and recheck.
Does it shake when it is in neutral?

 

[jakedaawg]

Water spraying from exhaust is completely normal. Water pouring like a hose is a different story.

 

[jakedaawg]

It also is normal to be able to go up 800 rpm with that motor and a 24' toon and not notice any more speed. I would be surprised if there is a speedo installed on a toon that would recognize this. We are talking less than a mph to 1-1/2 mph depending on prop pitch which I would guess to be an 11 or 13

 

[amishboy]

Pulled the prop, bent down two curled edges and filed off all the saw-tooth edging. Re-installed, problem solved. Runs smooth at all speed and maxes out at about 5500 rpm with 13 prop.

 

[amishboy]

Thanks for all the advice.