Thread Tools Search this Thread Display Modes
Old 06-13-2013, 11:36 AM   #1
Senior Member
kpinnn's Avatar
City: Thorndike
Country: USA
Vessel Name: Periwinkle
Vessel Model: Gulfstar 36
Join Date: Jun 2012
Posts: 110
Gulfstar MII Noise Level

One of our reasons for a shift from an express cruiser to a trawler is comfort level. I mean comfort while making headway. Reciently I looked at a MkII and started the two 62 HO diesels to check noise level. I foud it to be quite high 95 decibals while in neutral at 2000 RPM's and sitting in a slip. I am wondering if this is expected. Some of the conditions that might make a difference is 1st the boat was in a covered slip, second there was not a load on the engines. I also know that probably the cruise is about 1800 RPM's The 95 is actually higher than our express cruiser at 3000 rpn's and on plane. Or I should say close to the same level. Any comments? Is that an expected level? Do you think the conditions I mentioned can make a difference. I did not see any insulation on the undersides of the hatches to the engine room.


kpinnn is offline   Reply With Quote
Old 06-13-2013, 01:25 PM   #2
LaBomba's Avatar
City: Beaverton, Ontario
Country: Canada
Vessel Name: Looking Glass
Vessel Model: Carver 370 Voyager
Join Date: Nov 2012
Posts: 1,158
Ken, I have about 2" of insulation on the underside of my hatches, have only one engine but I am nowhere near 95 db, I would guess 80 to 85 tops and at 1800RPM. The covered slip, I would think, could have some effect.

LaBomba is offline   Reply With Quote
Old 06-13-2013, 01:56 PM   #3
Brooksie's Avatar
City: Cape Cod, MA
Country: USA
Vessel Name: Island Seeker
Vessel Model: Willard 36 Sedan
Join Date: Oct 2007
Posts: 1,032
Check your sound insulation in the engine compartment not just the hatch covers. Go to Soundown and read the information. There is no reason, with the materials available, that you should not be able to carry on a conversation at normal voice level with either 1 or 2 engines. On the other hand, it doesn't take much to screw up a good soundproofing job; meaning that a small un-noticed opening or lask of a gasket, can negate a lot of properly installed soundproofing material.
On Island Seeker, about the same size w/ single diesel, all you can hear when underway on the bridge is the bow wave. In the cockpit, the water splashing out the exhaust from the waterlift. Inside, a quiet conversation can be held anywhere.
Brooksie is offline   Reply With Quote
Old 06-13-2013, 07:08 PM   #4
City: VT
Country: USA
Join Date: Apr 2013
Posts: 12
I have a free app that has a decibel meter - SkyPaw - pretty cool. Pretty close to as good as a calibrated "real" one I use. Close enough to help you track down the areas where the sound is escaping.

If you establish a baseline and chart it different points on the boat at different rpms, as you make improvements you can see what gives you the best bang for the buck. Insulation quality as well as placement is key.

Good luck
Hardscrabble is offline   Reply With Quote
Old 06-13-2013, 10:26 PM   #5
BruceK's Avatar
Join Date: Oct 2011
Posts: 9,960
kpinnn, was that with the ER access hatch open or closed? I hope the former.
It would be unusual not to have the ER roof and hatch insulated. On one boat I had, I renewed the insulation,filling all gaps, and it helped a lot.
A lot of insulation panels are self adhesive (at first anyway) and easy to fit, so if there is none now, it can be done fairly easily, won`t cost much (in boat terms) and will be rewarding.
Island Gypsy 36 Europa "Doriana"
Sydney Australia
BruceK is offline   Reply With Quote
Old 06-14-2013, 06:41 AM   #6
FF's Avatar
Join Date: Oct 2007
Posts: 19,730
Time to spend some bucks,,,

Barrier Acoustic Insulation, Carpet Underlay - Soundown - Barrier ...‎
Soundown Barrier Composite Insulation is the most commonly used material due to its wide range of applications and excellent acoustic properties.

Soundown - peace and quiet for architectural, marine, & industrial ...‎
FOR PEACE AND QUIET. Worldwide Leader in Noise and. Vibration Control Engineering. ARCHITECTURAL · MARINE · INDUSTRIAL. Contact: Soundown ...Google+ page · Be the first to review
16 Broadway Salem, MA 01970
(978) 745-7000
FF is offline   Reply With Quote
Old 06-14-2013, 09:11 AM   #7
Northern Spy's Avatar
City: Powell River, BC
Country: Canada
Vessel Name: Northern Spy
Vessel Model: Nordic Tug 26
Join Date: Feb 2012
Posts: 3,023
Reading comprehension here folks. He doesn't own the boat he is looking and asks if loud is normal. No. It is not. As discussed most pilothouse boats require and have lots of sound insulation.
Northern Spy is offline   Reply With Quote
Old 06-14-2013, 10:31 AM   #8
Codger2's Avatar
City: San Diego
Country: US
Vessel Name: "Sandpiper"
Vessel Model: 2006 42' Ocean Alexander Sedan
Join Date: Oct 2007
Posts: 5,895
Originally Posted by BruceK View Post
On one boat I had, I renewed the insulation,filling all gaps, and it helped a lot.
I added a hatch for an easier access to my oil fill and coolant fill. At first blush, I didn't replace the sound insulation but after hearing the result, I added two sound deadening boxes to the underside of the hatch.
Attached Thumbnails
Click image for larger version

Name:	hatch.jpg
Views:	85
Size:	41.5 KB
ID:	20489   Click image for larger version

Name:	Coolant Cap After.jpg
Views:	79
Size:	90.8 KB
ID:	20490   Click image for larger version

Name:	DSCN1321.JPG
Views:	63
Size:	84.5 KB
ID:	20491  

Codger 1941.. Constant pursuit of the ultimate SoCal Cruising boat.
Codger2 is offline   Reply With Quote

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not 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 Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

All times are GMT -5. The time now is 05:40 PM.

Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012