Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 21-03-2011, 11:41   #1
Registered User
 
pdnervo's Avatar

Join Date: Aug 2007
Location: Marina Bay Richmond, Ca
Boat: 361 Beneteau
Posts: 41
Send a message via Skype™ to pdnervo
RPM's Question

Just got the boat.....i have a Westerbeke 30 in my 361 Beneteau.
at full throttle it rev's up to 2200 RPM only..amd cruises only about 4.5 knots.. how can i check and see what the problem is... i think it should rev up to 3000 while cruising.. is there a mobile tachometer i can install temporary to monitor the RPM's. thanx ans.
__________________

__________________
The wild geese do not intend to cast their reflection on the lake, the water has no mind to receive their image.
pdnervo is offline   Reply With Quote
Old 21-03-2011, 11:45   #2
Sponsoring Vendor
 
Tellie's Avatar

Community Sponsor

Join Date: Oct 2007
Location: Hollywood, Fl.
Boat: FP Athena 38' Poerava
Posts: 3,043
Re: RPM's question

Things to check first, is the prop clean, is the bottom clean, is the fuel and fuel lines clean, is the exhaust elbow clogged.
Tellie is offline   Reply With Quote
Old 21-03-2011, 12:35   #3
Registered User
 
pdnervo's Avatar

Join Date: Aug 2007
Location: Marina Bay Richmond, Ca
Boat: 361 Beneteau
Posts: 41
Send a message via Skype™ to pdnervo
Re: RPM's question

well the prop is clean the bottom is clean it was out of the water a couple weeks ago....boat is at mechanics and he is cleaning the fuel filter and hopefully the line.... cause the filter was green... but my question is can i or he put on an other temp gauge to check against the fixed gauge... i dont think the prop is a problem cause it would still turn and register the rpms no mater what prop is there... no or yes...tks ans
__________________
The wild geese do not intend to cast their reflection on the lake, the water has no mind to receive their image.
pdnervo is offline   Reply With Quote
Old 21-03-2011, 12:48   #4
Registered User

Join Date: Nov 2010
Location: Lafayette, Louisiana
Boat: Ketch, Hardin 45
Posts: 440
Images: 6
Re: RPM's question

One other minor detail; What is the govenor set at on your engine. It just might be 2200 RPM.
Going back to "Tellie"; What is the condition of the bottom of your boat?
__________________
boasun is offline   Reply With Quote
Old 21-03-2011, 13:56   #5
Registered User
 
bill good's Avatar

Join Date: Oct 2006
Location: Brisbane Australia
Boat: sold
Posts: 721
Re: RPM's question

the rpm can be checked with an optical tacho. what rpm do you get out of gear? the 2200 is that while under way?
__________________
bill good is offline   Reply With Quote
Old 21-03-2011, 14:04   #6
Registered User
 
pdnervo's Avatar

Join Date: Aug 2007
Location: Marina Bay Richmond, Ca
Boat: 361 Beneteau
Posts: 41
Send a message via Skype™ to pdnervo
Re: RPM's question

yep thats 2200 rpm under way....
__________________
The wild geese do not intend to cast their reflection on the lake, the water has no mind to receive their image.
pdnervo is offline   Reply With Quote
Old 21-03-2011, 14:18   #7
Senior Cruiser
 
SkiprJohn's Avatar

Cruisers Forum Supporter

Join Date: May 2006
Location: Kea'au, Big Island, Hawaii
Boat: Cascade, Sloop, 42 - "Casual"
Posts: 14,192
Re: RPM's question

There are digital tachometers that are easy to use and will tell you whether your boat tach is accurate. If someone installed a larger or higher pitched propeller than should be there it will keep your rpms down and cause your boat to lose speed. You might check out the propeller size. Check out the engine speed while in neutral to see if you can get the rated engine speed for your engine (probably 3500 to 4000) then put it in forward with the dock lines tied to see if you can get to 90% of that speed. If you can still only get 2200 rpms in neutral the trouble is with the engine and speed control or fuel. If you can get much higher in neutral than when in forward there is a problem with your drivetrain. Could be anywhere but I'd check to see if someone has changed the prop to larger. If there is a lot of heat on your stuffing box then there might be a problem with that being over tightened.
Hope you can sort it out.
kind regards,
__________________
John
SkiprJohn is offline   Reply With Quote
Old 21-03-2011, 14:23   #8
֍֎֍֎֍֎֍֎֍֎

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 13,022
Re: RPM's question

" can i or he put on an other temp gauge to check against the fixed gauge"
Go to Harbor Freight or something similar, $20 will buy you a non-contact infrared temperature sensor with a laser sight. You aim the dot on your engine and read the temperature display. You can also check the tire pressure in your car that way, if the temperature is the same on all 4, the pressure is the same. High temps = low pressure in that tire.
All sorts of uses once you own it.

If you call Beneteau, they're great at customer response, they'll tell you what speed that engine should be making at what rpm. Could be low compression, too.
__________________
hellosailor is offline   Reply With Quote
Old 21-03-2011, 14:30   #9
Registered User
 
pdnervo's Avatar

Join Date: Aug 2007
Location: Marina Bay Richmond, Ca
Boat: 361 Beneteau
Posts: 41
Send a message via Skype™ to pdnervo
Re: RPM's question

Hello Sailer the problem is with the tach not the temp gadge (my spelling mistake) but thanx your help....SkiprJohns answer was very helpful....thanks again. pn
__________________
The wild geese do not intend to cast their reflection on the lake, the water has no mind to receive their image.
pdnervo is offline   Reply With Quote
Old 21-03-2011, 14:55   #10
֍֎֍֎֍֎֍֎֍֎

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 13,022
Re: RPM's question

pn, no porblem. Similar answer: You can buy a "contact" tach, that you place in contact with a rotating part like your flywheel, or a non-contact 9optical) tach, that requires you to put a white dot on the rotating part. A good mechanic or engine shop should have one. If not, they aren't all that expensive if you can settle for a "consumer" grade one, which should be good enough for this use.
__________________
hellosailor is offline   Reply With Quote
Old 23-03-2011, 12:20   #11
Registered User

Join Date: Dec 2005
Posts: 26
Re: RPM's question

Might want to check the specs on this engine. I googled "Westerbeke 30" and the specs I saw indicate that 2200-2500 RPM might be about what it should max out at (its not a high-revving Yanmar). In fact, the performance graph only went to 3000 RPM and the torque curve peaked around 1800. I didn't see a redline, but "rule of thumb" is that you should cruise at around 80% of this figure.

If the throttle linkage is bottomed out and it still only runs at 2200 in neutral, that might be where its supposed to max out. If that is the case, you may be underpropped (i.e. the prop pitch should be increased). Did the previous owner replace the original prop with a folding or feathering version? If so, it might be incorrectly pitched. Such was the case when I bought my boat - the MaxProp was off 2-3 settings.
__________________
wallandj is offline   Reply With Quote
Old 23-03-2011, 12:34   #12
Senior Cruiser
 
SkiprJohn's Avatar

Cruisers Forum Supporter

Join Date: May 2006
Location: Kea'au, Big Island, Hawaii
Boat: Cascade, Sloop, 42 - "Casual"
Posts: 14,192
Re: RPM's question

Yes, by all means check the manual for the engine before adjusting things. If it is revving to 2200 and max is 2500 for your particular engine then you are in the ballpark for rpms. I didn't realize Westerbekes were a lower speed diesel. I guess I should have known because they are much like the Perkins.
Good luck and let us know how things work out.
kind regards,
__________________
John
SkiprJohn is offline   Reply With Quote
Old 23-03-2011, 12:39   #13
Registered User
 
pdnervo's Avatar

Join Date: Aug 2007
Location: Marina Bay Richmond, Ca
Boat: 361 Beneteau
Posts: 41
Send a message via Skype™ to pdnervo
Re: RPM's question

thanx i will get back to you soon im gonna haul it out in a couple weeks and look at the prop also...
thanx again for all the good info.. pn
__________________

__________________
The wild geese do not intend to cast their reflection on the lake, the water has no mind to receive their image.
pdnervo is offline   Reply With Quote
Reply

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
Engine wear at different RPM's Dockhead Engines and Propulsion Systems 20 05-03-2011 09:50
RPM's Yanmar 3GM engine bobelon Engines and Propulsion Systems 10 31-03-2009 11:42
KEEL/BALLAST QUESTION?? PLUS EXTRA CREDIT QUESTION ;) stephenronning Monohull Sailboats 3 21-03-2009 04:19
Question ??? Kiwineedhelp Meets & Greets 5 09-07-2008 23:20
Drop in RPM'S IN diesel engine candycat Engines and Propulsion Systems 20 07-04-2008 01:40



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 02:58.


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.