Reply
 
Thread Tools Search this Thread Display Modes
 
Old 11-04-2019, 10:57 AM   #1
Member
 
City: Normal, IL
Country: USA
Join Date: Oct 2018
Posts: 16
Cummins diesels

I see a lot of comments on cat and other diesels. I'm still in shopping mode but looking at either a 1988 42 jefferson or 45 Jefferson. Both have cummins diesels. Good or bad?
__________________
Advertisement

chuse927 is offline   Reply With Quote
Old 11-04-2019, 11:05 AM   #2
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 5,355
Cummins has made lots of different engines, some are gems and some not so much. Especially in the 80's. They were transitioning from one style (VT series) to the newer style (B and C series). The VT ones are now obsolete and hard to get parts for, the early B and C series had some bugs, but are still can be good machines. The later B and C (say starting in mid 90's) they got most of the bugs out.

Post exactly what engines are in there.
__________________

Ski in NC is offline   Reply With Quote
Old 11-04-2019, 11:07 AM   #3
Member
 
City: Normal, IL
Country: USA
Join Date: Oct 2018
Posts: 16
Quote:
Originally Posted by Ski in NC View Post
Cummins has made lots of different engines, some are gems and some not so much. Especially in the 80's. They were transitioning from one style (VT series) to the newer style (B and C series). The VT ones are now obsolete and hard to get parts for, the early B and C series had some bugs, but are still can be good machines. The later B and C (say starting in mid 90's they got most of the bugs out.

Post exactly what engines are in there.
6BTA 5.9 600 with 2100 hours. It's an 88 sun deck 42 Jefferson.
chuse927 is offline   Reply With Quote
Old 11-04-2019, 11:19 AM   #4
Guru
 
City: gulf coast
Country: pinellas
Join Date: Jun 2014
Posts: 2,798
600????
bayview is offline   Reply With Quote
Old 11-04-2019, 11:25 AM   #5
Member
 
City: Normal, IL
Country: USA
Join Date: Oct 2018
Posts: 16
Sorry. Both together are 600 hp. didnt mean to add that
chuse927 is offline   Reply With Quote
Old 11-04-2019, 11:39 AM   #6
Senior Member
 
wwestman's Avatar
 
City: Bellingham, WA
Country: USA
Vessel Name: Excellent Adventure
Vessel Model: 1995 Jefferson Ker Shine 45
Join Date: Apr 2015
Posts: 333
Those are what I have in my Jefferson and I am happy with them.
wwestman is offline   Reply With Quote
Old 11-04-2019, 11:43 AM   #7
Member
 
City: Normal, IL
Country: USA
Join Date: Oct 2018
Posts: 16
Any issues finding parts. Any major known issues?
chuse927 is offline   Reply With Quote
Old 11-04-2019, 12:21 PM   #8
Senior Member
 
firehoser75's Avatar
 
City: Nanaimo
Country: Canada
Vessel Name: Pilitak
Vessel Model: Nordic Tug 37
Join Date: Feb 2018
Posts: 324
Check out sbmar.com. Admittedly it is a site for a business that sells engines, parts, and service, but Tony Athens, the owner, provides tons of free info and help. He is acknowledged as a Cummins expert.
There are a couple of things I would say to check out thoroughly before purchase. The aftercoolers on these engines need regular, proper servicing (even Cummins does not service them properly if you want the longest life possible) using Tony's protocols from his site. If there are no records stating they have been serviced very recently, factor in new aftercoolers in your purchase price. Also, most early 6BTA's have Cummins exhaust elbows that are double jacketed with the raw water injected near the turbo. Pull off the elbow and look at the turbo. The elbow may have been giving the turbo a diet of saltwater and this would be bad! If that elbow is present, at the minimum plan on replacing it very soon with a custom elbow so that the water is injected below the "breakover point". Much info on Tony's site on all of this.
Good luck in your purchase decision.
__________________
Tom
Nanaimo, BC
firehoser75 is offline   Reply With Quote
Old 11-04-2019, 12:21 PM   #9
Senior Member
 
wwestman's Avatar
 
City: Bellingham, WA
Country: USA
Vessel Name: Excellent Adventure
Vessel Model: 1995 Jefferson Ker Shine 45
Join Date: Apr 2015
Posts: 333
Do the maintenance that the book calls for. These engines are what is in Dodge pickups and lots of over the road trucks. Same basic block. Easy to find parts. Easy to find someone to work on them, at least in the areas I have been in. And if, heavens forbid, you destroy one, Cummins remanufactured motors are available.
wwestman is offline   Reply With Quote
Old 11-04-2019, 12:34 PM   #10
Member
 
City: Normal, IL
Country: USA
Join Date: Oct 2018
Posts: 16
Thank you. I will check it out.
chuse927 is offline   Reply With Quote
Old 11-04-2019, 12:37 PM   #11
Guru
 
City: LI or Fla
Country: USA
Join Date: Jul 2013
Posts: 1,114
You got very good advise from all the above posts, I would only add get a cummin's mechanic to do the engine survey, I know some surveyors say they do both I like having a specialist.
Marlinmike is offline   Reply With Quote
Old 11-04-2019, 12:38 PM   #12
Member
 
City: Normal, IL
Country: USA
Join Date: Oct 2018
Posts: 16
Thanks
chuse927 is offline   Reply With Quote
Old 11-04-2019, 12:58 PM   #13
Senior Member
 
firehoser75's Avatar
 
City: Nanaimo
Country: Canada
Vessel Name: Pilitak
Vessel Model: Nordic Tug 37
Join Date: Feb 2018
Posts: 324
One more comment. There is another Nordic Tug owner that I know who has well over 9,000 hours on his 2001 6BTA and it is still running like a top. He goes from Seattle to Alaska every year.
__________________
Tom
Nanaimo, BC
firehoser75 is offline   Reply With Quote
Old 11-04-2019, 01:18 PM   #14
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 5,355
The 300hp 6BTA in the late 80's may have the old style heads with 9mm injector holes, and welded aftercooler. These engines did not hold up if run hard (like sportfish boats). Did fine in trawler service where they ran mostly easy. Many were upgraded to 7mm heads and the modern type aftercooler, then they held up as well as any.

Parts are very available, though some old stuff might need to be upgraded to new stuff, usually a good thing there. Prices generally lower than other brand engines, though still will sting depending on what you need. Run of the mill parts reasonable.

Post photos of the engines if you can.
Ski in NC is offline   Reply With Quote
Old 11-04-2019, 01:25 PM   #15
Member
 
City: Normal, IL
Country: USA
Join Date: Oct 2018
Posts: 16
Here is a photo from the ad. There are others. Click image for larger version

Name:	7263480_20191025181143928_1_LARGE.jpg
Views:	141
Size:	64.8 KB
ID:	96062
chuse927 is offline   Reply With Quote
Old 11-04-2019, 01:41 PM   #16
Senior Member
 
MV Wanderlust's Avatar
 
City: Lakeland
Country: United States
Vessel Name: Wanderlust
Vessel Model: 1999 Jefferson Rivanna 52'
Join Date: Feb 2018
Posts: 478
Lots of good info on the 6BTAs already posted. I'll add one more thing. The positioning of the front motor mount makes the raw water pump's impeller a little hard to get to. If the factory pump is installed, you often have to loosen the front motor mount and jack up the front of the engine about 1/4" to be able to get decent access. Some people have changed to an aftermarket water pump, Sherwood I think, that makes it easier. Other people have creatively modified impeller puller to make the job easier. Not a deal-breaker, by any means. Just something to be aware of.

John
__________________
John and Deb Easley
John - USCG 50 ton Master
1999 Jefferson Rivanna 52' CPMY
MV Wanderlust is offline   Reply With Quote
Old 11-04-2019, 02:52 PM   #17
Guru
 
RCook's Avatar


 
City: Holladay, UT
Country: USA
Vessel Name: Dream Catcher
Vessel Model: Nordic Tug 37-065
Join Date: Oct 2007
Posts: 619
The original pump is Sherwood. Much better aftermarket pump is Seamax from Seaboard Marine. First thing I did on our NT 37 with Cummins 6BTA 5.9 M3 330hp was replace that Sherwood pump with the Seamax.

https://www.sbmar.com/product/smx-1730-seawater-pump/
__________________
Richard Cook
Dream Catcher (Nordic Tug 37-065)
"Cruising in a Big Way"
RCook is offline   Reply With Quote
Old 11-04-2019, 02:52 PM   #18
Guru
 
BandB's Avatar
 
City: Fort Lauderdale
Country: USA
Join Date: Jan 2014
Posts: 17,441
Cummins, in general, have a very solid reputation. Their use as marine propulsion is just one small part of their overall use, from trucks to being the leading selling marine generator. Also, they have a good reputation for service and standing behind their product. I look at how they stood up to help DHayes. First class.
BandB is offline   Reply With Quote
Old 11-04-2019, 04:15 PM   #19
Senior Member
 
firehoser75's Avatar
 
City: Nanaimo
Country: Canada
Vessel Name: Pilitak
Vessel Model: Nordic Tug 37
Join Date: Feb 2018
Posts: 324
Chuse927,
From your photo, those are definitely the "stock" exhaust elbows I was talking about. You will need new "custom" exhaust elbows ASAP, plus you need to check the exhaust side of the turbo for saltwater damage. In a worst case, the engines could have been on a saltwater diet with the turbo shot and maybe even damage into the engine! Definitely get that checked out as in the worst case scenario it could be very expensive!
From that photo I can't tell which Aftercooler they have.
__________________
Tom
Nanaimo, BC
firehoser75 is offline   Reply With Quote
Old 11-04-2019, 04:45 PM   #20
Guru
 
Ski in NC's Avatar
 
City: Wilmington, NC
Country: USA
Vessel Name: Louisa
Vessel Model: Custom Built 38
Join Date: Jan 2014
Posts: 5,355
No fan of that mixer either, but at least the one visible has a decent down-angle on it so should drain ok. The ones that drain usually live. But we are talking 30yrs!!

Aftercooler "looks" like the modern one. A pic of inboard side of stbd would tell for sure.
__________________

Ski in NC 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 06:52 PM.


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
×