problem diagnosis needed, no speed, smoke, low rpms - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > On Board > Gear & Maintenance
 Not a Member? 


Like Tree5Likes
Reply
 
LinkBack Thread Tools
  #1  
Old 01-09-2013
Junior Member
 
Join Date: Aug 2010
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
thegreenflash is on a distinguished road
problem diagnosis needed, no speed, smoke, low rpms

I'm relatively new to sailboat maintenance and I've got problem. My engine is a Yanmar 75 turbo with a hurth v-drive and maxprop. boat is csy 44. I've been on a mooring for 5 months at st augustine and have not done any bottom maintenance since we arrived and planned on doing so only when we were moving the boat. I took the boat out for a short spin yesterday and could not get 1/4 knot of speed and would not tach up over 1500 rpms. I saw black smoke and some oil spitting out of the exhaust when trying to rev over 1500. The engine usually cruises at 2700 rpms. I dove under the boat very briefly due to very cold water and saw about 20 barnacles on the prop, small, but nothing that would cause that kind of performance. It seems like the shaft is somehow restricted. I didn't immediately see anything caught on running gear, but again, it was very cold. The speed was fine upon arrival in st augustine in August. I expected performance loss from growth, but not rpm restrictions. In neutral, it will tach up no problem. I have not changed the fuel filters yet. The performance issues are the same in forward and reverse. I will be under the boat tomorrow with a wet/dry suit and have more time, what should I look at? During the summer we were having a significant shaft vibration, I'm thinking maybe the cutlass bearing is going bad. Any thoughts would be appreciated.
Steve
Reply With Quote Share with Facebook
  #2  
Old 01-09-2013
Senior Member
 
Join Date: Feb 2010
Location: SW FLORIDA
Posts: 121
Thanks: 3
Thanked 1 Time in 1 Post
Rep Power: 5
algee is on a distinguished road
Re: problem diagnosis needed, no speed, smoke, low rpms

I would try the simple fix first-- hire a diver to clean the prop, shaft, and the bottom. Also have him make sure there are no rope or fishing lines restricting the prop and shaft.
Reply With Quote Share with Facebook
  #3  
Old 01-09-2013
chef2sail's Avatar
Senior Member
 
Join Date: Nov 2007
Location: Maryland
Posts: 6,810
Thanks: 28
Thanked 52 Times in 48 Posts
Rep Power: 7
chef2sail will become famous soon enough
Send a message via AIM to chef2sail
Re: problem diagnosis needed, no speed, smoke, low rpms

You problem is proababaly shaft related, whether its growth or cutlass.

I would venture to say if all was fine before it is growth. Its amazing how a few barnacles can retard the boat speed.

Thats the simple solution. More complicated could be shaft misalignment, a bad cutless bearing, or the coupling especially since you said you felt vibration, but again growth can cause that also. Think simple first.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
___________________________
S/V Haleakala (Hawaiian for" House of the Sun")
C&C 35 MKIII Hull # 76
Parkville, Maryland
(photos by Joe McCary)
Charter member of the Chesapeake Lion posse

Our blog-
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.


“Sailing is just the bottom line, like adding up the score in bridge. My real interest is in the tremendous game of life.”- Dennis Conner
Reply With Quote Share with Facebook
  #4  
Old 01-09-2013
PorFin's Avatar
Señor Member
 
Join Date: Sep 2007
Posts: 1,340
Thanks: 1
Thanked 8 Times in 8 Posts
Rep Power: 7
PorFin is on a distinguished road
Re: problem diagnosis needed, no speed, smoke, low rpms

Since we're all guessing here...

Since it ran correctly in August, I'm more inclined to think it's likely not an alignment or cutlass bearing issue. Prop wrap seems much more likely.

How about the v-drive? Can you freely turn the shaft by hand when the tranny's in neutral? Is the fluid at the proper level?
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
________
'85 BYB Vagabond 39
Reply With Quote Share with Facebook
  #5  
Old 01-09-2013
Junior Member
 
Join Date: Aug 2010
Posts: 7
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
thegreenflash is on a distinguished road
Re: problem diagnosis needed, no speed, smoke, low rpms

I haven't tried to spin the shaft in neutral, I will tomorrow..The fluid level is normal, the transmission is rather loud going into and out of gear, I'm guessing that is because the shaft doesn't want to turn right away and the trannie has to provide alot of torque for the first rotation. The exposed shaft in the engine room is under the engine, kinda hard to get a hand on it, I will try to spin it from the prop under water. I've got a diver cleaning it up today. Is it common to drop 50% of your rpms just due to barnacles? If any growth was restricting the cutlass, wouldn't it have broken loose immediately. Just for arguments sake, if the running gear is clean, and nothing stuck on the prop, what else could cause the shaft to not want to rotate?
Reply With Quote Share with Facebook
  #6  
Old 01-09-2013
MarkofSeaLife's Avatar
Senior Member
 
Join Date: Nov 2010
Posts: 1,947
Thanks: 25
Thanked 39 Times in 36 Posts
Rep Power: 4
MarkofSeaLife is on a distinguished road
Re: problem diagnosis needed, no speed, smoke, low rpms

Its the bottom and the prop growth.

Don't worry about expensive things like cutless barings, shafts and engines. it will be the barnacles on the prop and grown on the bottom.

First Mate Yachting Services have a diver contracted to them. Give them a yell and get your bottom done then give it another go. It's a cheap, simple cure to what appears to be a huge problem.




Mark
__________________
Sea Life
Notes on a Circumnavigation:
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

Last edited by MarkofSeaLife; 01-09-2013 at 09:40 AM.
Reply With Quote Share with Facebook
  #7  
Old 01-09-2013
Senior Member
 
Join Date: Dec 2008
Posts: 642
Thanks: 0
Thanked 2 Times in 2 Posts
Rep Power: 6
lancelot9898 is on a distinguished road
Re: problem diagnosis needed, no speed, smoke, low rpms

My first suspension is that a fishing line may be causing that shaft not to spin properly. However after you dive on the boat and can turn the shaft while in neutral that would rule that out. I too have a max prop and while it has been flawless in the past 25 years of use just as a check make sure that it is rotating properly.
Reply With Quote Share with Facebook
  #8  
Old 01-09-2013
Senior Member
 
Join Date: Dec 2006
Location: Beacon, NY
Posts: 1,862
Thanks: 13
Thanked 59 Times in 57 Posts
Rep Power: 8
miatapaul is on a distinguished road
Re: problem diagnosis needed, no speed, smoke, low rpms

I think the first thing I would do is get a pair of good gloves and a paint scraper, scrub brushes, scrubbing pads, put on a mask and fins to try cleaning it up a bit myself to see if that makes a change.

It seems deferring maintenance is never a good idea.
Reply With Quote Share with Facebook
  #9  
Old 01-09-2013
FarCry's Avatar
Freedom 39
 
Join Date: Apr 2007
Location: St Thomas USVI
Posts: 871
Thanks: 0
Thanked 13 Times in 13 Posts
Rep Power: 8
FarCry is on a distinguished road
Re: problem diagnosis needed, no speed, smoke, low rpms

Quote:
Originally Posted by thegreenflash View Post
I haven't tried to spin the shaft in neutral, I will tomorrow..The fluid level is normal, the transmission is rather loud going into and out of gear, I'm guessing that is because the shaft doesn't want to turn right away and the trannie has to provide alot of torque for the first rotation. The exposed shaft in the engine room is under the engine, kinda hard to get a hand on it, I will try to spin it from the prop under water. I've got a diver cleaning it up today. Is it common to drop 50% of your rpms just due to barnacles? If any growth was restricting the cutlass, wouldn't it have broken loose immediately. Just for arguments sake, if the running gear is clean, and nothing stuck on the prop, what else could cause the shaft to not want to rotate?
Can't you grab the prop shaft where it comes out of the back side of the Hurth V drive on the shaft coupling rather than try and reach under the engine?
Reply With Quote Share with Facebook
  #10  
Old 01-09-2013
jrd22's Avatar
Courtney the Dancer
 
Join Date: Nov 2000
Location: San Juan Islands., WA, USA
Posts: 3,808
Thanks: 3
Thanked 14 Times in 14 Posts
Rep Power: 14
jrd22 will become famous soon enough
Re: problem diagnosis needed, no speed, smoke, low rpms

I would guess the max prop is stuck in the feathered position. Doesn't take much growth to keep the blades from rotating. My brothers Auto prop was stuck from non-use, had the same symptoms you are describing.
Faster and chef2sail like this.
__________________
John
SV Laurie Anne

1988 Brewer 40 Pilothouse

Reply With Quote Share with Facebook
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Problem starting Yanmar 2QM20H and white smoke when running epp Diesel 10 07-30-2010 01:20 AM
Another Exhaust Smoke Diagnosis DrB Diesel 1 07-06-2010 09:46 AM
The Color of Smoke and What the problem could be CarelessNavigator Diesel 0 04-05-2010 02:12 PM
White Smoke from Older Diesel at Higher RPMs kcoffey Gear & Maintenance 3 06-24-2004 03:23 PM
Yanmar (3GM 20hp) Blue Smoke Problem animaashi Gear & Maintenance 3 11-05-2001 06:18 PM


All times are GMT -4. The time now is 12:16 PM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012