Prop fouling

[eric]

Hi
I ran into something underwater last night with my EC21. She shut down hard. It was stuck in forward position on the shift lever and could not move to neutral. Also could not start because it could not go to neutral. The gear box seemed stuck. So I figured I had a small log or something jammed in prop. I bit the bullet and went under to feel around. It was late evening and the bay is really muddy right now so no seeing anything. But did not feel anything either. I ended up removing the shift linkage at the motor end. Was able to get the shift lever to neutral and jogged the motor a bit. Then gear box freed up and I was able to put everything together and proceed to my overnight anchor place. Today after a great nights sleep aboard and a nice day crabbing I loaded to head home. Thats when I discovered I had picked up some stray rope. It ran fine all day but here is my concern. When I cut and removed the rope (nylon) I could tell that there was a lot of friction at some point as the rope was melted. And it looked like a black gasket or something was melted into the rope. Right now when I look at my prop and look forward towards the area that the shaft goes into boat bottom there is nothing but the shaft. Im wondering if there is a bushing or something that should be between back side of prop leading to where shaft comes out of boat bottom. No water leaked in or anything. And it ran fine. But on pullout there was about 6 wraps of dock line like rope. Anyone have picture of prop and shaft? By the way. The EC21 is a great little crabbing boat. So responsive moving back and forth among the traps. I am smitten with this boat.
Eric Pa

 

[thataway]

You should have a cutlass bearing on the area where the shaft exits the keel (in some boats this is supported by a skeg). This is basically a hard rubber or plastic material which is water lubricated and has some loose tolerance. When a rope is caught on a prop shaft, it can melt, and cause damage to the cutlass bearing. There is some range to the transmission of the cutlass bearing is damaged, or if the shaft is damaged.

You want to put in a new cutlass bearing, and check the shaft for run out.

 

[RProffer]

I just looked at my prop and I can see about an inch of shaft between the aft side of the prop and the forward side of a brass fitting about two inches in diameter. After looking at the following link, my guess is the brass fitting is the cutlass bearing on the R21EC. http://www.diybob.com/diyCutlessBearing.htm

If you can freely turn your prop while in neutral and there is no side-to-side movement, and there is no vibration or noise, my guess is you are probably okay. If you are really concerned, you can pay to have a professional to look at it.

 

[eric]

Your description is what I needed. Im all fine then. No water all day crabbing....no vibration....and I have about an inch of exposed shaft from rear of prop to cutles bearing. With nothing covering that exposed section of shaft.
My concern was that exposed section if it had a covering on it or anything.
Thanks a lot. Great boat. Great support.
Eric Pa

 

[abcandjrc]

When you say no water I assume you mean no significant accumulation.

I am also assuming you know that while underway at moderate RPM your stuffing box should be dripping a bit of water. Opinions vary from 2-3 drops per minute to 8-10, but some light flow is necessary to keep the cutlass bearing and the packing in the stuffing box cool and lubricated. Otherwise they will be destroyed with possible resulting damage to the shaft.

We lost a cutlass bearing on our Crealock 37 once when it picked up heavy monofilament fishing line. It did not melt since there was sufficient water flow but it ate away at the rubber of the cutlass bearing and ruined it. There was noticeable shaft movement side-to-side in that instance.

Unfortunately, stuffing boxes are generally buggers to adjust, and it looks like the one on our R21-EC will be a bugger-plus due to such narrow access. I'm due to find out since ours is currently dripping at least once a second.

 

[eric]

yes. Thank You. There is some water coming in. Not enough to be concerned about. No play in shaft.
Eric