Atomic 4 Shakes the Boat - SailNet Community
 3Likes
Reply
 
LinkBack Thread Tools
post #1 of 18 Old 08-16-2012 Thread Starter
Junior Member
 
Join Date: Aug 2012
Location: Seattle, WA
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Atomic 4 Shakes the Boat

I purchased a Cat27 last summer and am hooked. She has an Atomic 4 that runs like a horse.

Last weekend as i was headed back into port (under power at top speed) the boat suddenly lost a lot of speed and the motor got loud, the boat also started to shake. I throttled back on the gas and ran it at almost idle; the shaking stopped and i made it back into port.

I had a mechanic inspect it and he found nothing noticeably wrong with it.

I took her out for a test run to see if the issue persists; it does, when in low speed it runs fine, as soon as i gas her up she starts to shake and although the motor speeds up, the boat itself does not.

Does this sound familiar to anyone?
Ringoparr is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #2 of 18 Old 08-16-2012
Member
 
Join Date: Sep 2008
Location: Vancouver, BC
Posts: 63
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 7
 
Check for something fouling the prop.
KBuckley is offline  
Quote Quick Reply Share with Facebook
post #3 of 18 Old 08-16-2012
Member
 
Join Date: Feb 2012
Posts: 36
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Does it shake when you Rev it in neutral?

Probably not.

Almost certain you have fouled shaft
Sic Semper Tyrannis is offline  
Quote Quick Reply Share with Facebook
post #4 of 18 Old 08-16-2012
1975 Newport 28
 
jaschrumpf's Avatar
 
Join Date: Jun 2002
Location: Monrovia, MD
Posts: 573
Thanks: 0
Thanked 1 Time in 1 Post
Rep Power: 14
 
Re: Atomic 4 Shakes the Boat

Atomic 4s are some notoriously smooth-running engines. If you're getting vibration on that scale it's something else than the engine.

S/V Free Spirit

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

Monrovia, MD
jaschrumpf is offline  
Quote Quick Reply Share with Facebook
post #5 of 18 Old 08-17-2012
Chastened
 
BubbleheadMd's Avatar
 
Join Date: Nov 2009
Location: Edgewater/Annapolis
Posts: 3,354
Thanks: 2
Thanked 81 Times in 76 Posts
Rep Power: 6
 
Send a message via Yahoo to BubbleheadMd
+1 on the fouled prop or shaft. Also inspect engine mounts.

Fixed prop or folding?

S/V Old Shoes
1973 Pearson 30 #255
BubbleheadMd is offline  
Quote Quick Reply Share with Facebook
post #6 of 18 Old 08-17-2012
Learning the HARD way...
 
eherlihy's Avatar
 
Join Date: Jan 2007
Location: Boston / Ft Myers Area
Posts: 4,038
Thanks: 158
Thanked 106 Times in 103 Posts
Rep Power: 9
 
Re: Atomic 4 Shakes the Boat

Prop, prop shaft (and cutlass bearing), engine mounts..
eherlihy is online now  
Quote Quick Reply Share with Facebook
post #7 of 18 Old 08-17-2012 Thread Starter
Junior Member
 
Join Date: Aug 2012
Location: Seattle, WA
Posts: 5
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Re: Atomic 4 Shakes the Boat

The mounts we're fine and no, there is no shaking while in neutral... It's surprising (or maybe not) that my mechanic didn't mention anything about the prop. I'm going to jump in the water this afternoon to take a peek, i'll post a follow up... thank god its a hot day; 91 degrees in Seattle.
Ringoparr is offline  
Quote Quick Reply Share with Facebook
post #8 of 18 Old 08-17-2012
Member
 
Join Date: Feb 2012
Posts: 36
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Take a good sharp knife with you. Bet you need it!

Sent from my Kindle Fire
Sic Semper Tyrannis is offline  
Quote Quick Reply Share with Facebook
post #9 of 18 Old 08-17-2012
TQA
Bombay Explorer 44
 
TQA's Avatar
 
Join Date: Apr 2009
Posts: 2,914
Thanks: 0
Thanked 79 Times in 75 Posts
Rep Power: 7
 
Re: Atomic 4 Shakes the Boat

Bread knife works best IMHO.
TQA is offline  
Quote Quick Reply Share with Facebook
post #10 of 18 Old 08-18-2012
Senior Slacker
 
SlowButSteady's Avatar
 
Join Date: Feb 2010
Location: SoCal
Posts: 4,223
Thanks: 0
Thanked 17 Times in 15 Posts
Rep Power: 6
 
Re: Atomic 4 Shakes the Boat

When you say that the motor got loud, did it sound like the exhaust got louder or was it more of a thumping/vibration? If it's the former then there may well be something wrong with the engine itself. If the latter, like others have said, it's probably a fouled prop, bad motor mount, bad cutlass bearing, or some combination of those.


BTW, I would look for a new mechanic if I were you.

Never forget them. Do something to prevent it from happening again.
Charlotte Bacon, Daniel Barden, Rachel Davino, Olivia Josephine Gay, Ana M. Marquez-Greene, Dylan Hockley, Dawn Hochsprung, Madeleine F. Hsu, Catherine V. Hubbard, Chase Kowalski, Jesse Lewis, James Mattioli , Grace McDonnell, Anne Marie Murphy, Emilie Parker, Jack Pinto, Noah Pozner, Caroline Previdi, Jessica Rekos, Avielle Richman, Lauren Rousseau, Mary Sherlach, Victoria Soto, Benjamin Wheeler, Allison N. Wyatt

Last edited by SlowButSteady; 08-18-2012 at 02:24 AM.
SlowButSteady is offline  
Quote Quick Reply Share with Facebook
Reply

Tags
atomic 4 , catalina 27 , shaking , speed

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
Wind Generator Shakes Boat DocBrauer Electrical Systems 13 09-14-2011 11:32 AM
How much for an Atomic 4? jarcher Atomic 4 20 07-14-2010 03:31 PM
cal 34 atomic 4 tygertyger Atomic 4 1 07-09-2006 09:44 AM
China Shakes World Economy, Rattling Boeing, VW, ThyssenKrupp (Bloomberg.com) NewsReader News Feeds 0 04-11-2006 10:15 PM
ode to the atomic 4 jwellsfamily4 Gear & Maintenance 1 08-04-2003 11:13 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome