Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 06-08-2008, 07:44   #1
Registered User

Join Date: Jul 2008
Location: Vancouver Island
Boat: 27ft catalina
Posts: 492
yanmar performance issue

good day everyone my wife and i just went out for a sea trial on a 1980 catalina 27 with a brand new 1gm10 yanmar. this boat was advertised as being capable of cruising at 6knots but when we took it out it was only running 3.8 miles/hr at 3000 rpm, disappointed i asked the broker why it seemed so slow he told me that the bottom hadnt been out for a couple of years and that crud on the hull and prop were most likely the cause. myself being very new to sailboats am curious if this could in fact be the problem or are we looking at something else. any thoughts or suggestions ? thanks
__________________

__________________
michaelmrc is offline   Reply With Quote
Old 06-08-2008, 07:52   #2
Registered User
 
speciald@ocens.'s Avatar

Join Date: Apr 2008
Location: On the boat - Carib, Chesapeake
Boat: 58 Taswell AS
Posts: 1,139
Sure can slow you down. Racers dry sail their boats for a reason. I didn't see in your note where the boat has been for the last two years but in Annapolis with brackish water - the bottom can get crudy in a few months. Realize that sailboats have much smaller motors than powerboats. Growth on the prop and bottom will have much more effect on speed through the water.
__________________

__________________
speciald@ocens. is offline   Reply With Quote
Old 06-08-2008, 08:09   #3
Marine Service Provider
 
AnchorageGuy's Avatar

Join Date: Mar 2003
Location: Wherever the boat is!
Boat: Marine Trader 34DC
Posts: 4,618
If the bottom is fouled and the prop really fouled the boat will not perform well and I have seen instances where it would not even move.
__________________
Chesapeake Bay, ICW Hampton Roads To Key West, The Gulf Coast, The Bahamas

The Trawler Beach House
Voyages Of Sea Trek
AnchorageGuy is offline   Reply With Quote
Old 06-08-2008, 08:27   #4
Senior Cruiser
 
Talbot's Avatar

Cruisers Forum Supporter

Join Date: Jun 2004
Location: Brighton, UK
Boat: Privilege 37
Posts: 3,579
Images: 32
6 kts on a 27 ft boat with a 1GM - with a clean bum and a gale behind perhaps.

and it would have to be flat calm as welll!

5 kts more likely, and reducing considerably if wind against
__________________
"Be wary of strong drink. It can make you shoot at tax collectors - and miss."
Robert A Heinlein
Talbot is offline   Reply With Quote
Old 06-08-2008, 09:17   #5
sitting on the dock of the bay

Join Date: Mar 2006
Posts: 1,513
Images: 6
Send a message via Yahoo to gonesail
the catalina 27 is 7000 lbs ... so it seems a little underpowered with the 1GM 10. i had a 7000 lb. 28 footer with a 2GM and it would not do 6 knots under power.
__________________
sometimes the things that may or may not be true are the things a man needs to believe in the most.
gonesail is offline   Reply With Quote
Old 06-08-2008, 11:09   #6
Registered User

Join Date: Mar 2008
Location: Houston TX
Boat: Pacific Seacraft 25 "Turtle"
Posts: 364
Images: 35
When my boat sat for 2 years........

it would hardly move at all because the prop was so badly fouled. It looked like 3 balls of shells. Now I clean the prop every couple of months just to be sure. Even a light coating of small barnicles will slow my boat considerably. My YSM8R will push my PSC25(5000lb+ loaded) at about 5kts at full throttle with a spotless bottom and a clean prop. Usually I putt around at 3.5kts and don't strain the 30yo motor any more than required. I got good and stuck this weekend rescueing a couple of boneheads in a 12ft johnboat with a dead electric motor and only one lifejacket between them about a mile of shore. I had to really lay the coal to the old girl and she finally chugged her way free of the mud. I don't remember them saying much of a thankyou though......m
__________________
I must go down to the sea again.........
cantxsailor is offline   Reply With Quote
Old 06-08-2008, 13:57   #7
Senior Cruiser
 
Alan Wheeler's Avatar

Cruisers Forum Supporter

Join Date: Dec 2003
Location: Marlborough Sounds. New Zealand
Boat: Hartley Tahitian 45ft. Leisure Lady
Posts: 8,038
Images: 102
I think you get the answer within the comments above. But certainly 6kts is being overly optimistic for a boat of that length. And any growth with that power is going to slow you dramatically.
__________________
Wheels

For God so loved the world..........He didn't send a committee.
Alan Wheeler is offline   Reply With Quote
Old 06-08-2008, 14:11   #8
Registered User

Join Date: Jul 2008
Location: Vancouver Island
Boat: 27ft catalina
Posts: 492
thanks everyone for all the info, had no idea that hull crud and growth would have such an affect on the performance.
__________________
michaelmrc is offline   Reply With Quote
Old 06-08-2008, 20:04   #9
Registered User
 
Ziggy's Avatar

Join Date: Apr 2008
Location: U.S., Northeast
Boat: Contessa 32
Posts: 1,421
Images: 2
Quote:
Originally Posted by Talbot View Post
5 kts more likely, and reducing considerably if wind against
I agree with Talbot, 5 knots in optimal conditions, less with fouled bottom or mismatched prop.
__________________
Ziggy is offline   Reply With Quote
Old 06-08-2008, 20:41   #10
Eternal Member
 
Chief Engineer's Avatar

Join Date: Aug 2006
Location: North of Baltimore
Boat: Ericson 27 & 18' Herrmann Catboat
Posts: 3,798
I have a question.

You say advertised at 6 knots but then say you were going 3.8 miles per hour.(3.2Knots)

How were you measuring your speed...over the ground or thru the water?
__________________
Chief Engineer is offline   Reply With Quote
Old 06-08-2008, 21:00   #11
cruiser

Join Date: Aug 2005
Location: No longer post here
Boat: Catalac Catamaran
Posts: 2,462
I have two 1GM10's (2 bladed props) in my boat and have to clean my props every 4 months. It takes about 30 minutes a prop unless I wait 6 months and then it's about an hour per prop.

If I don't clean them, I'm lucky to be able to move out of my slip at all, forget making any kind of speed.
__________________
Tropic Cat is offline   Reply With Quote
Old 06-08-2008, 21:45   #12
Moderator
 
Boracay's Avatar

Cruisers Forum Supporter

Join Date: Feb 2004
Location: Pelican Bay, Great Sandy National Park
Boat: Steel Roberts Offshore 44
Posts: 5,175
Images: 18
Big growth + small prop = slow

Boracay has a 22" prop so even with considerable fouling we still make good speed.
I had a 32' ferro a few years ago with a 7hp Yanmar and with the prop fouled it would not move at all.
With a waterline length of 36' we should be seeing 8.4kts but I'm lucky to get 7 most days.
With a waterline length of 21.75' you could be looking at 6.5 knots with all planets in perfect alignment. This does not happen very often.
__________________
Rust never sleeps
Boracay Blog.
Boracay is offline   Reply With Quote
Old 06-08-2008, 23:20   #13
Registered User
 
Celestialsailor's Avatar

Join Date: Nov 2006
Location: In Mexico, working on the boat
Boat: Hallberg Rassy 35. and 14ft.Whitehall pulling skiff.
Posts: 8,013
Images: 5
I imagine you could possibly achieve 6+ knots....over a waterfalls...he he he
__________________
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming: Wow - what a ride!"

http://wwwjolielle.blogspot.com/
Celestialsailor is offline   Reply With Quote
Old 09-08-2008, 18:32   #14
Registered User

Join Date: Jul 2008
Location: Vancouver Island
Boat: 27ft catalina
Posts: 492
chief we were using our lowrance x27 gps to tell us our speed.
__________________
michaelmrc is offline   Reply With Quote
Old 09-08-2008, 19:37   #15
Senior Cruiser
 
S/V Antares's Avatar

Cruisers Forum Supporter

Join Date: Sep 2007
Location: Annapolis, Bahamas
Boat: 1983 Gulfstar 36
Posts: 1,249
Images: 1
There are hundreds of Catalina 27's on the Chesapeake. Even with the 3 cyl universal they are a 5 kn boat. With any chop less. The dealer/broker is giving you bull.

Get online with one of the Catalina Owners groups and get some real opinions from other owners.
__________________

__________________
Will & Muffin
Lucy the dog

"Yes, well.. perhaps some more wine" (Julia Child)
S/V Antares is offline   Reply With Quote
Reply

Tags
yanmar

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Newbie Issue elcubanito Monohull Sailboats 23 18-03-2008 20:31
Grounding Plate Issue markpj23 Construction, Maintenance & Refit 32 22-02-2008 19:17
Network Issue Announcement Andy R Forum News & Announcements 0 17-08-2007 00:05
Atomic 4 issue DaveK Engines and Propulsion Systems 23 03-09-2006 13:22



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 17:18.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.