Reply
 
Thread Tools Search this Thread Display Modes
 
Old 08-11-2019, 10:44 AM   #1
Member
 
City: Vero Beach, Fl
Country: USA
Join Date: Dec 2012
Posts: 15
Engine Hours

I am looking at a trawler that has the Cummins 4bt 3.9 150HP engine. The vessel was purchased new in the mid 1980's by a naval engineer. It has been serviced and maintained very well. The engine has 7000 hours on it. Should I be concerned? What would be the lifespan of this engine if properly serviced and never abused?
Thanks
John
__________________
Advertisement

JohnRB is offline   Reply With Quote
Old 08-11-2019, 11:14 AM   #2
Senior Member
 
gsholz's Avatar
 
City: PDX
Country: Northwest
Vessel Name: Lady Anne
Vessel Model: GB 52 Europa
Join Date: Nov 2016
Posts: 221
Given the hours the engine must be well matched to the boat and been well taken care of. As long as you keep the sea water side serviced (no overheating), there is no reason you cannot go to 10-12,000 hours and beyond with regular maintenance.
__________________

gsholz is offline   Reply With Quote
Old 08-11-2019, 11:22 AM   #3
Guru
 
caltexflanc's Avatar
 
City: North Carolina for now
Country: USA
Vessel Name: Small Incentive
Vessel Model: Boston Whaler 130 Sport
Join Date: Aug 2011
Posts: 5,158
The only way to get even an approximate potential lifespan for that engine is to have an experienced Cummins surveyor do a thorough inspection. Are there running and maintenance logs available? Actual lifespan will be largely dependent on how you run it and care for it.
__________________
George

"There's the Right Way, the Wrong Way, and what some guy says he's gotten away with"
caltexflanc is offline   Reply With Quote
Old 08-11-2019, 11:37 AM   #4
Member
 
City: Vero Beach, Fl
Country: USA
Join Date: Dec 2012
Posts: 15
Thanks for the responses. The engine and trawler were maintained very well. No expense spared and all issues were addressed immediately. The original owner is now 93y.o. and this was his baby. He was a marine engineer by trade and designed weapons systems for the navy. There are complete log books of everything done to both the hull and engine/generator since new. The high hours result from multiple cruises around the great loop and the Florida coasts as well as Caribbean. Much of that travel was done between 1500-1800 rpms. The trawlers home port was on the upper Mississippi so much of its life has been spent in fresh water and I would estimate that 70% of the hours have been in fresh water. 7,000 hours gives me some pause but knowing it's history and care; I am thinking it may have a lot of life yet. Just being cautious.
JohnRB is offline   Reply With Quote
Old 08-11-2019, 11:47 AM   #5
Senior Member
 
City: Qualicum Beach, Vancouver Island
Country: Canada
Vessel Name: Capricorn
Vessel Model: Mariner 29 - Express Cruiser 1969
Join Date: Feb 2019
Posts: 425
Here is a good article comparing gas with diesel marine engines. Its good because it will give you a realistic appraisal of the maintenance of the diesel engine. Based on this article, high hours on a diesel is far better than low hours due to corrosion.

Of course most know that keeping up with necessary maintenance on an engine is better than not doing it, but you will see key items to check to see if this maintenance was done. Based on this article, I'd guess a rebuild will be in your future. Based on what you said about the guy and the boat, I'd still get the boat knowing a rebuild will be around the corner sooner than latter.

https://www.yachtsurvey.com/GasDiesel.htm
rsn48 is offline   Reply With Quote
Old 08-11-2019, 12:03 PM   #6
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 5,266
Engine should have lots of life left in it at 7k hrs. Worst case a 4BT long block is not very expensive.

If it checks out well, worry not.

I'd rather have one with 7k in good shape than one with 1k that sat long term.
Ski in NC is offline   Reply With Quote
Old 08-11-2019, 12:32 PM   #7
Guru
 
jleonard's Avatar
 
Join Date: Jun 2008
Posts: 3,423
Those are tough little motors. There are tons of them around in delivery trucks such as Frito-Lay, UPS, Fedex, etc.
Lots of mechanics can work on them.
__________________
Jay Leonard
Attitude Adjustment
40 Albin
Mystic,Ct. /New Port Richey,Fl
jleonard is offline   Reply With Quote
Old 08-11-2019, 01:04 PM   #8
Member
 
City: Vero Beach, Fl
Country: USA
Join Date: Dec 2012
Posts: 15
Given the regular maintenance and use; I am leaning toward its going to be good for quite a while. As ski in nc said it's better that it was used and didn't sit. The owner regularly used the boat up until this spring. He is now too old and has decided to part with it. Thanks to all for the advice.
__________________

JohnRB is offline   Reply With Quote
Reply

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 12:21 AM.


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