| Author |
Message |
    
Joe Pirelli
| | Posted on Sunday, April 11, 2004 - 03:33 am: | 
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I have a 27' wooden boat with a perkins in it. What sort of speeds can I expect to attain with the right transmission/prop combo. Right now it has the wrong combo and does 4.5 knots @ 2500 rpm.
Any ideas? Suggestions?
Thanks
jpirelli@pirelliweb.com |
Rufus
| | Posted on Wednesday, April 28, 2004 - 01:51 am: |
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Prop is easier to change. Use the prop spec'ing sites on the internet as a start. Try to keep the clearance between the tip of the prop and hull larger than the minimum spec'd - saves prop wear, noise and vibration. That's a whole lot of motor for that boat. |
David
| | Posted on Friday, April 30, 2004 - 02:51 pm: |
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I am trying to find some information on the rpm range of the Perkins 4-108 diesel engine. I have read/heard that if you run the engine at 1800 rpms you get more longivity and less headaches than if you try to run closer to 3800. Anybody know anything about this issue or where more information can be located.
Thanks
David |
roy abrams
| | Posted on Friday, May 07, 2004 - 06:01 pm: |
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4 108s should be very happy up to 2800 rpm run it at what sounds sweet but change the oil often |
jocelyne robitaille
| | Posted on Tuesday, May 18, 2004 - 08:27 pm: |
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We have a 1977 ChrisCraft with an 4cyl Perkins 90hp and we are looking for the service manual for the engine.... |
Mike Kerutis
Visitor
| | Posted on Friday, August 25, 2006 - 06:28 pm: |
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The Perkins 4-108 shop book that I have states that the MAX RPM for a pleasure boat is 3600 RPM and MAX RPM for Commercial applications 3800 to 4000 RPM
Common knowledge states that, for a pleasure boat, you should run at 80% of top rated RPMs.
For cruising speed. That would make the top cruising RPM 2880.
Hope this helps
Mike |
Lawrence Paul Beasley
New member
Username: rig30mechanic
Post Number: 1
Registered: 09-2006
| | Posted on Thursday, September 21, 2006 - 08:46 pm: |
|
I have a 30 foot, 76 year old classic cruiser with a 4-108. It is pretty narrow and I cruise all day at 7.5knots at 2400revs (with a clean bum). The "hull speed" rule is 1.4 times the square root of the water line length (feet) which gives me a "hull speed" of 7 knots. I can push 9 knots but the fuel consumption goes through the roof. |
leonopit
Visitor
| | Posted on Friday, January 11, 2008 - 03:14 am: |
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I am about to go cruising in a 33ft Ketch that has a 4-108. I am looking for a good book on diesel engine maintenance and repair that would be relevant to the 4-108. Any suggestions please? |
Dwight Brooker
Member
Username: sailmaster
Post Number: 66
Registered: 05-2006
| | Posted on Friday, January 11, 2008 - 06:19 am: |
|
Other than the original Perkins service manual an excellent book that covers most boat systems including diesels is Niger Calder's "Boat Owner's Mechanical and Electrical Manual" second edition.
You can find it at any West Marine, Boater's World or Boat US store. It is the bible for cruisers. |
