Strange growth on prop and cutlas bearing

[Shelman]

Anybody ever seen marine growth like this?
Its our fourth year in the same slip here in Oregon and first time seeing anything like this. Its only on the prop, prop zink, and coming out of the strut/cutlas bearing.
its kind of chalky and flaky, not soft.
It was getting so thick I had to dive on the prop and scrape it off because we had lost a full knot of speed while motoring. At first I was worried it was an epic case of galvanic corrosion but thankfully is not.
I think I would have to pull the prop shaft to get it out of the bearing. I can't imagine there could be any cooling flow through the bearing grooves with this stuff filling the water passages.

 

[Alan Gomes]

Perhaps it is caused by El Nino, or the "Blob," or....?

http://www.oregonlive.com/weather/index.ssf/2015/06/el_nino_effect_on_the_pacific.html

 

[Shelman]

Haha yea it has been the calmest year on the water I have ever seen. It could be something out of the ordinary caused by warmer water temp I suppose.

 

[Christian Williams]

Looks like some weird lime deposit by nefarious sea creatures. If so, muriatic acid or Lime-away should remove easily.

I've had glop on my prop, too. Diver seems to have trouble getting it off.

 

[Shelman]

Both good ideas. Thanks guys. Ill keep you posted on the resolution however mundane it may prove to be.

 

[toddster]

Well, I do see deposits like that on rocky reefs in the area. I think it's calcite and on rocks, it's probably caused by algae growth. I'd tend to suspect some sort of galvanic reaction going on in your drive train to make it go that fast.

 

[Shelman]

So....... I tried the lime away which did dissolve some of the calcium deposit but after three weeks of applying it in the evenings I got impatient and just scraped off all the deposits in about an hour. The larger issue I now face is that the cutlass bearing has developed a vice like grip on the prop shaft. I didn't notice it until yesterday after I had finished adjusting the valve clearance and re-torquing the head. I ran the engine to warm it up and to see shat my motor sounds like with properly adjusted valves, but when I threw the transition into gear the engine came to a very abrupt stop. For a while I thought I had some kind of issue with my transition, but I eventually disconnected the shaft coupling from the transition output flange and it was clear the heavy friction was in the cutlass bearing and not the transmission. So either the calcium deposit hardened over the winter and is causing increased friction, or the lime away swelled the cutlass bearing.
My next step is to try and pull the prop shaft but we probably already know how easy it will be to persuade the shaft coupling to come off the end of the prop shaft. I am pickling it in pb-blaster right now so I wont know for a few days, but if that doesn't want to come off I may try and make a jig (poor mans Strut/Pro) to push the cutlass bearing out with the shaft still in place.
I'll keep you all posted on how it comes out. (or doesn't lol)

 

[Alan Gomes]

So....... I tried the lime away which did dissolve some of the calcium deposit but after three weeks of applying it in the evenings I got impatient and just scraped off all the deposits in about an hour. The larger issue I now face is that the cutlass bearing has developed a vice like grip on the prop shaft. I didn't notice it until yesterday after I had finished adjusting the valve clearance and re-torquing the head. I ran the engine to warm it up and to see shat my motor sounds like with properly adjusted valves, but when I threw the transition into gear the engine came to a very abrupt stop. For a while I thought I had some kind of issue with my transition, but I eventually disconnected the shaft coupling from the transition output flange and it was clear the heavy friction was in the cutlass bearing and not the transmission. So either the calcium deposit hardened over the winter and is causing increased friction, or the lime away swelled the cutlass bearing.
My next step is to try and pull the prop shaft but we probably already know how easy it will be to persuade the shaft coupling to come off the end of the prop shaft. I am pickling it in pb-blaster right now so I wont know for a few days, but if that doesn't want to come off I may try and make a jig (poor mans Strut/Pro) to push the cutlass bearing out with the shaft still in place.
I'll keep you all posted on how it comes out. (or doesn't lol)

Randy,
From everything I know about cutless bearings you should never run the engine in gear with the boat out of the water. The bearing needs to be immersed in water to keep it lubricated.

 

[Shelman]

Randy,
From everything I know about cutless bearings you should never run the engine in gear with the boat out of the water. The bearing needs to be immersed in water to keep it lubricated.

I spray it with the hose and then run it for three or four seconds just to turn the oil in the transmission, but yes otherwise it would heat up and cause damage.

 

[Shelman]

Woo hoo! I was able to get the coupler off of the shaft without breaking or cutting anything. After a week long soak with the pb-blaster and a home made puller it only took me three hours working the wrenches to pry them apart. There was some very noticeable polishing on the shaft where it was covered by the strut but I don't think it is deep enough wear to have ruined the prop shaft. Maybe I'll post a picture of it along with a measurement from my calipers for those who know more than me to coment on.

 

[Shelman]

My calipers read of course .75 on the un-worn portion of the shaft and .747 on the worst of the worn portion that was under the strut.