Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 18-06-2014, 06:50   #16
Registered User

Join Date: Apr 2013
Posts: 4,880
Re: Bullet Proof Diesel

The reports on Yanmar are more likely the result of volume.If 1 in 10,000 motors will sieze in the next year (regardless of brand) and there are 50,000 Yanmars of various ages floating around and 100 of brand X motors, odds are you will see 5 Yanmars siezed per year and you may never see a brand X fail even if they have the same failure rate.

That said, we love our 4stroke EFI outboard. Simple, quiet, fuel efficent and worst case scenario $5k and we have an entirely new drivetrain. Pluse we have directional thrust, so we can back as easily as going forward. Nothing at all like the old 2 strokes. Of course, our boat was designed for outboard power. If you are cobbling an outboard onto a boat designed for diesel inboard, that's a different situation.
__________________

__________________
valhalla360 is offline   Reply With Quote
Old 18-06-2014, 06:53   #17
Wayfaring Mariner
 
captain58sailin's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: Homer, AK is my home port
Boat: Skookum 53'
Posts: 4,045
Images: 5
Re: Bullet Proof Diesel

I would never buy a diesel named "brand X" that is just asking for trouble
__________________

__________________
" Wisdom; is your reward for surviving your mistakes"
captain58sailin is offline   Reply With Quote
Old 18-06-2014, 07:06   #18
Registered User
 
Blue Crab's Avatar

Join Date: Sep 2009
Location: Hurricane Highway
Boat: Cal 29
Posts: 3,883
pirate Re: Bullet Proof Diesel

Wish I had a good feeling about running my Yanmar 2GMFW20 around 2200. Lotsa folks say thats too slow but it's easier on me. It's economical and close to hull speed.

Some say idling kills them, others get 10K hours.

We can put a man on the moon but don't have definitive answers for simpler stuff.
__________________
Blue Crab is offline   Reply With Quote
Old 18-06-2014, 07:20   #19
Moderator
 
a64pilot's Avatar

Cruisers Forum Supporter

Join Date: Oct 2013
Location: Albany Ga.
Boat: Island Packet 38
Posts: 17,055
Re: Bullet Proof Diesel

Buy the boat you want, regardless of the engine brand, don't accept a baot you really don't like because it has the right engine.

My personal caveat to that is I won't have a Volvo, if I found a boat I really had to have that had a Volvo in it, I'd figure re-powering cost into the price.

I don't care who makes the engine, you don't want it raw water cooled. Outboards get away with raw water cooling, but I believe that is because they are a clean sheet design to use raw water cooling, most if not all boat Diesels are adapted from terrestrial designs and "marinized"
__________________
a64pilot is offline   Reply With Quote
Old 18-06-2014, 07:21   #20
Wayfaring Mariner
 
captain58sailin's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: Homer, AK is my home port
Boat: Skookum 53'
Posts: 4,045
Images: 5
Re: Bullet Proof Diesel

I have had extensive conversations with marine engineers about the best speed to run a Detroit diesel for longevity and fuel consumption. The answer I got was 1700 rpm would get me the best of both. This was for a 471 or 671.
__________________
" Wisdom; is your reward for surviving your mistakes"
captain58sailin is offline   Reply With Quote
Old 18-06-2014, 07:29   #21
Senior Cruiser
 
colemj's Avatar

Cruisers Forum Supporter

Join Date: Oct 2005
Location: Presently on US East Coast
Boat: Manta 40 "Reach"
Posts: 10,049
Images: 12
Re: Bullet Proof Diesel

Quote:
Originally Posted by captain58sailin View Post
I have had extensive conversations with marine engineers about the best speed to run a Detroit diesel for longevity and fuel consumption. The answer I got was 1700 rpm would get me the best of both. This was for a 471 or 671.
These are 2-stroke, 2000rpm engines. 1700 would be very low for a smaller, higher rev engine.

Most engine manufacturers publish rpm curves for HP and fuel consumption. There is no "best" general rpm - that is dependent on the specific engine and the load it is under.

Mark
__________________
www.svreach.com

You do not need a parachute to skydive. You only need a parachute to skydive twice.
colemj is offline   Reply With Quote
Old 18-06-2014, 07:39   #22
Registered User
 
mbianka's Avatar

Join Date: Mar 2008
Posts: 2,125
Images: 1
Re: Bullet Proof Diesel

Diesels and sailboats don't mix. I found that out when my good running Westerbeke 27 went from perfectly running engine to a non starter in six hours. Despite oil changes every 50 hours and/or seasonally, zinc and antifreeze changes etc. Diesels work best and last longest when driven hard and often. Not for minutes at a time to get out of the harbor. Expect the diesel to fail at some point no matter what manufacturer. Then your choice is repair/rebuild, replace or as I did change to electric propulsion. It may not suit everybody but, in seven years with EP my maintenance cost have dropped pretty close to zero in comparison to the previous diesel engine.
__________________
Capt. Mike
mbianka is offline   Reply With Quote
Old 18-06-2014, 07:44   #23
Certifiable Refitter/Senior Wannbe
 
Wotname's Avatar

Cruisers Forum Supporter

Join Date: Jan 2008
Location: South of 43 S, Australia
Boat: Van DeStat Super Dogger 31'
Posts: 7,331
Re: Bullet Proof Diesel

Quote:
Originally Posted by a64pilot View Post
Buy the boat you want, regardless of the engine brand, don't accept a baot you really don't like because it has the right engine.

My personal caveat to that is I won't have a Volvo, if I found a boat I really had to have that had a Volvo in it, I'd figure re-powering cost into the price.

I don't care who makes the engine, you don't want it raw water cooled. Outboards get away with raw water cooling, but I believe that is because they are a clean sheet design to use raw water cooling, most if not all boat Diesels are adapted from terrestrial designs and "marinized"
Hmm... I have only had 4 engines but they were all raw water cooled. I haven't ever experienced a problem with raw water cooling but I suppose there will come a time. I do hear about heat exchangers giving problems but having never owned one, I can't really comment further.

AFAIK, Bukh & Yanmar both used a "clean sheet" design for their raw water cooled engines.

I concur that terrestrial designs would be better off with a heat exchanger.
__________________
All men dream: but not equally. Those who dream by night in the dusty recesses of their minds wake in the day to find it was vanity: but the dreamers of the day are dangereous men, for they may act their dreams with open eyes, to make it possible. T.E. Lawrence
Wotname is offline   Reply With Quote
Old 18-06-2014, 07:52   #24
Registered User
 
Panope's Avatar

Join Date: Sep 2012
Location: Washington State
Boat: Colvin, Saugeen Witch (Aluminum), 34'
Posts: 1,593
Re: Bullet Proof Diesel

Quote:
Originally Posted by Blue Crab View Post
Wish I had a good feeling about running my Yanmar 2GMFW20 around 2200. Lotsa folks say thats too slow but it's easier on me. It's economical and close to hull speed.

Some say idling kills them, others get 10K hours.

We can put a man on the moon but don't have definitive answers for simpler stuff.
BC: I would operate the engine as per the Yanmar operations manual. Not sure what yours recommends, but mine tells me "when oparing the engine at reduced power settings, race the engine every 2 hours". The process for racing the engine is described as moving the control handle from idle to max speed and back to idle 5 times while transmission is in neutral.

The above implies that yanmar does not think it is bad to run the engine slow.

Steve
Panope is online now   Reply With Quote
Old 18-06-2014, 07:59   #25
Registered User

Join Date: Feb 2013
Location: WY / Currently in Hayes VA on the Chesapeake
Boat: Ocean Alexander, Ocean 44
Posts: 922
Re: Bullet Proof Diesel

Be sure to note the difference between "Raw water cooling" in which sea water flows through the engine block, which is bad, and "Sea water cooled" or some other phrase in which the sea water flows through heat exchangers for the engine and transmission which is good. Keel cooling also has many advocates.

I've run several boats with Yanmars. I think they are good engines. My irritation with them and Volvo is that the companies won't give you cross reference numbers so you can go to a tractor dealer or NAPA and get parts. My friend had a 2 month night mare stuck in Columbia while Volvo shipped the required parts to Minnesota the to the US Virgin Islands before finally sending them where she asked them to send the stuff in the first place. My old Ford Lehman engines are supported anywhere in the world. If I were looking at newer engines I would lean towards Beta at 100HP and below and John Deere above that. That said if I saw a boat that I wanted at the right price I might own another Yanmar or Volvo. Everything is a trade off.....
__________________
darylat8750 is offline   Reply With Quote
Old 18-06-2014, 08:12   #26
Certifiable Refitter/Senior Wannbe
 
Wotname's Avatar

Cruisers Forum Supporter

Join Date: Jan 2008
Location: South of 43 S, Australia
Boat: Van DeStat Super Dogger 31'
Posts: 7,331
Re: Bullet Proof Diesel

Quote:
Originally Posted by darylat8750 View Post
Be sure to note the difference between "Raw water cooling" in which sea water flows through the engine block, which is bad, and "Sea water cooled" or some other phrase in which the sea water flows through heat exchangers for the engine and transmission which is good. Keel cooling also has many advocates.

.....
Hmm... am I the only one who thinks "raw water cooling" is quite OK - assuming engine is designed for it. As posted above, I have yet to have a problem with raw water cooling - over 4 engines to date.

Maybe I have just been lucky
__________________
All men dream: but not equally. Those who dream by night in the dusty recesses of their minds wake in the day to find it was vanity: but the dreamers of the day are dangereous men, for they may act their dreams with open eyes, to make it possible. T.E. Lawrence
Wotname is offline   Reply With Quote
Old 18-06-2014, 08:17   #27
Registered User
 
Blue Crab's Avatar

Join Date: Sep 2009
Location: Hurricane Highway
Boat: Cal 29
Posts: 3,883
pirate Re: Bullet Proof Diesel

Quote:
Originally Posted by Panope View Post
BC: I would operate the engine as per the Yanmar operations manual. Not sure what yours recommends, but mine tells me "when operating the engine at reduced power settings, race the engine every 2 hours". The process for racing the engine is described as moving the control handle from idle to max speed and back to idle 5 times while transmission is in neutral.

The above implies that yanmar does not think it is bad to run the engine slow.

Steve
Yeah, I read that and blew on by it. That is good to know.
__________________
Blue Crab is offline   Reply With Quote
Old 18-06-2014, 08:22   #28
Registered User

Join Date: Aug 2009
Location: Kimberton PA
Boat: Cabo Rico 38 / Bayfield 32
Posts: 573
Images: 1
Re: Bullet Proof Diesel

Quote:
Originally Posted by Wotname View Post
Hmm... am I the only one who thinks "raw water cooling" is quite OK - assuming engine is designed for it. As posted above, I have yet to have a problem with raw water cooling - over 4 engines to date.

Maybe I have just been lucky
If the engine was designed from the ground up to be raw water (read SALT water) cooled, it should provide reasonable service. Raw water cooled engines will usually be designed to run at cooler temperatures than fresh water (coolant) cooled engines. This is to prevent precipitation of salts in the engine's cooling passages. The thermostat's opening temperature will be selected for that lower temperature. Machining tolerances will also be selected for the lower run temperature. The downside is that a diesel engine will run less efficiently at the cooler temperature. Diesel engines run best when hot. (but obviously not so hot that they damage themselves)
__________________
Saltyhog is offline   Reply With Quote
Old 18-06-2014, 08:40   #29
Registered User
 
ranger42c's Avatar

Join Date: Aug 2012
Location: Maryland, USA
Boat: 42' Sportfish
Posts: 2,984
Re: Bullet Proof Diesel

Quote:
Originally Posted by Fullblown View Post

Thanks for all your advice, I can see now that a Yanmar would be okay if it has been looked after and that begs the question, how would I know if its been looked after. Do I ask for service records, probably hard if the boat is over twenty years old and had a few owners. Do I insist on engine report before buying.


Yes, it's common to ask for -- and then actually look at , when supplied -- service records. Yes its common to have a separate engine report (aka mechanical survey), even in addition to a service record review. Usually the latter is best performed by a specialist in whatever brand engine you're examining.

Cooling with a heat exchanger is often called "fresh water cooling" around here. Fresh water (more likely a mixture of -- ideally -- distilled water and anti-freeze) is routed via several small freshwater tubes through a larger heat exchanger jacket which has sea water continuously pumped through it and then out through a wet exhaust.

-Chris


-Chris
__________________
Selby Bay, South River, Chesapeake Bay, USA.
ranger42c is offline   Reply With Quote
Old 18-06-2014, 09:40   #30
Wayfaring Mariner
 
captain58sailin's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: Homer, AK is my home port
Boat: Skookum 53'
Posts: 4,045
Images: 5
Re: Bullet Proof Diesel

Doesn't hurt to send in an oil sample for analysis. Even if you don't have a historical record, it will give you an idea in general about the status of the engine condition.
__________________

__________________
" Wisdom; is your reward for surviving your mistakes"
captain58sailin is offline   Reply With Quote
Reply

Tags
diesel

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
Proof of vat paid kenpatt Europe & Mediterranean 24 17-05-2017 03:49
Need Puppy-Proof Lifeline Netting (Cheap) Doghouse Construction, Maintenance & Refit 66 09-10-2013 16:01
New spill proof CARB approved diesel 5 gallon container sailorchic34 Auxiliary Equipment & Dinghy 24 01-10-2012 06:26
Water proof levels of canvas? Jack Long Construction, Maintenance & Refit 2 04-10-2008 10:17
Sales Taxes - Proof of being out of state?? Dan1 Dollars & Cents 25 16-09-2008 22:57



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 19:29.


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.