Vibration from forward to neutral - 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 > General Interest Forums > Gear & Maintenance
 Not a Member? 
  #1  
Old 06-29-2008
Junior Member
 
Join Date: Jun 2008
Posts: 25
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
gsyversen is on a distinguished road
Vibration from forward to neutral

Hey all, had a nice weekend sailing but noticed something new docking today. I went forward on slow/idle (slowest forward) and went to neutral, when we came to a stop there was a big ruckus from the engine and I thought it stalled but it didnt, the RPM came back up (wasnt looking at the tach but thats what it sounded like) and everything was ok...

anyone know what this is and is it something I should worry about ? hoping my transmission isnt causing this, it sounded more like a idle going too low...

My engine is a Yanmar 3GM30F and boat is a Beneteau, transmission is kanzai.

any tips would be appreciated !

Gaute
Reply With Quote Share with Facebook
  #2  
Old 06-30-2008
Senior Member
 
Join Date: Sep 2006
Posts: 2,179
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 8
Rockter will become famous soon enough
How's the gearbox oil lube level?
Reply With Quote Share with Facebook
  #3  
Old 06-30-2008
sailingdog's Avatar
Telstar 28
 
Join Date: Mar 2006
Location: New England
Posts: 43,291
Thanks: 0
Thanked 8 Times in 8 Posts
Rep Power: 13
sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice sailingdog is just really nice
Did you wrap something on the shaft... that might cause the engine to slow and resume like that... If the rope or object wasn't too long, it would just slow the engine as it wrapped, and then it would resume power as it just spun.
__________________
Sailingdog

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

Telstar 28
New England

You know what the first rule of sailing is? ...Love. You can learn all the math in the 'verse, but you take
a boat to the sea you don't love, she'll shake you off just as sure as the turning of the worlds. Love keeps
her going when she oughta fall down, tells you she's hurting 'fore she keens. Makes her a home.

—Cpt. Mal Reynolds, Serenity (edited)

If you're new to the Sailnet Forums... please read this
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
.

Still—DON'T READ THAT POST AGAIN.
Reply With Quote Share with Facebook
  #4  
Old 06-30-2008
Joesaila's Avatar
1977 Morgan OI 30
 
Join Date: May 2007
Location: Massachusetts
Posts: 438
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 7
Joesaila is on a distinguished road
I have the same engine. Low idle will do that. Minimize 1000rpm. Best to stay around 1500+ w diesels. So says jwayent@jwayent.net He's a pro.
__________________
My formula for living is quite simple. I get up in the morning and I go to bed at night. In between, I occupy myself as best I can.
Cary Grant
Reply With Quote Share with Facebook
  #5  
Old 06-30-2008
Junior Member
 
Join Date: Jun 2008
Posts: 25
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
gsyversen is on a distinguished road
gearbox oil is fine, thogh I'm planning on replacing it soon, and I dont think somethings around the shaft. I had a look under the boat and a diver was on it just a few days ago, it was only temporary and stopped once the rpm came up... I normally go close to the continuous rating on the engine when we'r moving but when docking I go slower
Reply With Quote Share with Facebook
  #6  
Old 06-30-2008
Senior Member
 
Join Date: Nov 2002
Location: New York
Posts: 5,315
Thanks: 0
Thanked 14 Times in 14 Posts
Rep Power: 14
bubb2 has a spectacular aura about bubb2 has a spectacular aura about bubb2 has a spectacular aura about
gsyversen, the following link may be of use to you.

Yanmar 2GM20F
Reply With Quote Share with Facebook
  #7  
Old 07-02-2008
Junior Member
 
Join Date: Jun 2008
Posts: 25
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
gsyversen is on a distinguished road
interesting article, I'll post there to see how they adjusted/found how much slack there was.... thanks all !
Reply With Quote Share with Facebook
  #8  
Old 07-02-2008
DrB DrB is offline
Senior Member
 
Join Date: Mar 2007
Location: New England
Posts: 953
Thanks: 0
Thanked 5 Times in 5 Posts
Rep Power: 8
DrB will become famous soon enough
Interesting subject

I have the Yanmar 3GM30F model also and a few weeks ago, I couldn't believe how much the thing was vibrating when idle soon after start-up. It only did this once, maybe twice, on separate occasions. Once above about 1100 RPM, the motor really smoothed out. The odd thing was, once I dropped it back into the normal idle range (700 to 800 RPM) after a few minutes, the vibration was gone. Maybe the engine was a little cold.

Since then, I don't notice it as much. I still think overall the motor vibrates more than other marine diesels, but (knock on wood), it has been very reliable for me.

Quote:
Joesaila I have the same engine. Low idle will do that. Minimize 1000rpm. Best to stay around 1500+ w diesels. So says jwayent@jwayent.net He's a pro.
I think 1000 RPM is too high for idle. I have never heard Yanmar quote that number. Most 3GM30's that I know of idle around 800 RPM.
I found this on a Yanmar reference site:

Idle Table - Yanmar Motors

DrB
Reply With Quote Share with Facebook
  #9  
Old 07-07-2008
Junior Member
 
Join Date: Jun 2008
Posts: 25
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
gsyversen is on a distinguished road
I'v noticed that its not so much cold engine on mine but when I quickly take it from forward to reverse, like when docking... or when just quickly putting it in neutral from forward-faster-than-slowest. this most often happen during docking and sometimes it just can't be avoided though I try my best. the link said that the throttle cable was stretched over time and it cut the idle down so much it dropped a cylinder... the symptoms sounds similar, anyone know how to adust the idle or is it just using the tach ?

Gaute
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
Shaft Vibration in Forward but not reverse bstrebe Gear & Maintenance 6 10-28-2003 07:17 AM
The Balance of Hull and Sails Steve Colgate Buying a Boat Articles 0 05-25-2000 08:00 PM


All times are GMT -4. The time now is 03:09 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