Another season, another problem. My engine, at full throttle, wouldn't go above 1700 rpm and the boat wouldn't go above 5 to 5.5 knots under power. Reverse works fine. I have an Autoprop. Another fact is that with the engine running but the transmission in neutral, it feels as if the boat is being slowed by a knot or so compared to having the engine off (and the transmission engaged in forward). There is no unusual vibration and the engine runs smoothly and revs fully in neutral. Under load it runs hotter than normal.
My guess is that there is a problem with the autoprop. I am having a short haul this week to find out for sure. Perhaps I snagged something.
Any other ideas about what might be causing this?
Thanks for any responses.
Elliott
Elliott Milstein
Collaboration #1469
1995 C-36MkII
Port Annapolis Marina
Elliott,
I think I agree with you that there is a problem with the autoprop. My guess would be that one or more blades are "frozen" in place and will not rotate. Have you had it serviced recently? Has it been greased lately? If not, then most likely barnacles and other crud have gotten in the bearings. The earlier style autoprops should be dis-assembled and cleaned yearly. The newer style needs to be greased yearly.
Tom Sokoloski
C36/375IA Past Commodore
Noank, CT
If the water in Annapolis is warm enough (should be), you can simply dive beneath the boat and check out the prop. It sure sounds like that is the problem.
Duane Ising - Past Commodore (2011-2012)
s/v Diva Di
1999 Catalina 36 Hull #1777
Std rig; wing keel, M35B, Delta (45#)
Punta Gorda, FL
http://www.sailblogs.com/member/diva-di/
Elliott,
Sounds like you are on the right trail. Is the engine exhaust black when trying to go above 1700 RPM. If so the engine is getting the fuel but is too heavily loaded to bring up the RPM.
There are some recent posts about the Auto Prop, most folks love theirs. Tom Sokoloski made a comment in one of these recent post about the importance of lubrication every year on this prop to keep it fuctioning.
You may want to ping Tom about what your are seeing.
Steve
Cepheus dream
C36 MK I # 825
MK I Tech Editor No Mas
What is an auto prop?
Capt. Sam Murphy
1994 Catalina 36, Hull 1327
Shoal draft, two cabin model.
Panama City, Florida
Work got me on my last post, hamered it out over about thirty minutes between calls at work before posting. Did not go back to the site until later that night to see Tom had beat my reply. Told you he would have a suggestion.
Cepheus dream
C36 MK I # 825
MK I Tech Editor No Mas
Yes, Tom, I do have it serviced every year but I don't think it got more than lubed last year. I could dive down but logistics and time are going to trump common sense and thus the short-haul. I will post when I hear back from Port Annapolis Marina. Sometimes I think I keep them in business.
Elliott Milstein
Collaboration #1469
1995 C-36MkII
Port Annapolis Marina
The cause of this problem: the prop and shaft fouled with massive numbers of barnacles. The boat was last hauled in July of 2012 and the bottom cleaned and painted. I have never seen this much crud on my boat. Perhaps I didn't use it enough. I didn't get out in November or April as I usually have. The auto prop is otherwise fine. Thanks to all for your ideas.
Elliott Milstein
Collaboration #1469
1995 C-36MkII
Port Annapolis Marina
Two words-
"hull cleaner"
Clean bottoms are FastBottoms!
Elliott, thanks for reporting your findings.
A member maybe 5 years ago tried running his engine at the dock with the prop engaged and had a similar result to yours. He was very reluctant to believe it could be prop fouling because he had a diver come every 4-5 weeks.
Guess what, he said the prop blades were barely visible amongst the giant 'ball' of barnacles. I would have loved to hear the conversation he had with the diver.
Duane Ising - Past Commodore (2011-2012)
s/v Diva Di
1999 Catalina 36 Hull #1777
Std rig; wing keel, M35B, Delta (45#)
Punta Gorda, FL
http://www.sailblogs.com/member/diva-di/
[QUOTE=deising;18177]
A member maybe 5 years ago tried running his engine at the dock with the prop engaged and had a similar result to yours. He was very reluctant to believe it could be prop fouling because he had a diver come every 4-5 weeks.
Guess what, he said the prop blades were barely visible amongst the giant 'ball' of barnacles. I would have loved to hear the conversation he had with the diver.[/QUOTE]
Yeah, except in this case the OP hadn't had his bottom or running gear cleaned since he splashed the boat almost a year ago. But thanks for the five-year-old second-hand anecdote denigrating divers. :rolleyes:
Clean bottoms are FastBottoms!
I use Pettit zinc barnacle barrier coat and it seems to give very good protection on prop and shaft ,just go by instructions on can
Bill Miller
S/V Lorraine
Pacific Northwest,Sound Sound
Grapeview,Wa
1990 Mk1
[QUOTE=fstbttms;18179]Yeah, except in this case the OP hadn't had his bottom or running gear cleaned since he splashed the boat almost a year ago. But thanks for the five-year-old second-hand anecdote denigrating divers. :rolleyes:[/QUOTE]
Don't have a first name for you, fstbttms, but I trust you realize I was only denigrating THAT particular diver. I have always dived my own bottom, but I have known many great divers who earn every penny they charge. As fast as word-of-mouth travels amongst boaters, I would imagine the small percentage of 'problem' divers gets weeded out pretty quick.
Cheers!
Duane Ising - Past Commodore (2011-2012)
s/v Diva Di
1999 Catalina 36 Hull #1777
Std rig; wing keel, M35B, Delta (45#)
Punta Gorda, FL
http://www.sailblogs.com/member/diva-di/
[QUOTE=deising;18181]Don't have a first name for you, fstbttms, but I trust you realize I was only denigrating THAT particular diver. I have always dived my own bottom, but I have known many great divers who earn every penny they charge. As fast as word-of-mouth travels amongst boaters, I would imagine the small percentage of 'problem' divers gets weeded out pretty quick.[/QUOTE]
[img]http://www.fotolode.com/images/fstbttms/Emoticons/bigthumbup.gif[/img]
Although you might be surprised (as I continually am) at how many second-rate hull cleaners manage to stay in business.
Clean bottoms are FastBottoms!