cummins recon 5.9

sevenjohn

Lieutenant Commander
Joined
Jun 9, 2012
Posts
178
Likes
34
Location
groveland
Boat Make
novi
I am in the process of rebuilding a young bros 33,and trying to settle on an engine. I have looked at the new 265 jd and the qsb cummins. The boat is a pre 2000 so I can put in a recon cummins 315 hp....what are the facts on a "recon" engine? I prefer a mechanical engine and an engine with no proprietary systems so my local mechanic can work on the engine after the warranty expires.
 

BillD

Admiral
Joined
Sep 1, 2011
Posts
7,748
Likes
3,453
Location
Portsmouth NH.. Piscataqua and Merrimack Rivers
Boat Make
27 H&H with Cummins QSB 5.9 480 power
Except for the Bosch P7100 fuel injection pump (remanufactured from Bosch), the Cummins RECON mechanical 6BTA engines are "all new" from the Cummins factory in Mexico.

Delco starter, Delco alternator are new. New STORM engine block and new innards.
Aftercoolers, heat exchangers are new. I'm confident you'll not find a "remanufactured" part in or on the engine.

The Cummins 6B 5.9 series engine is one of the best inline sixs ever produced. There are over 3 million in 6B 5.9s in use all over the world in all diesel industries.

Parts are cheap, the engines are easy to repair and you will NEVER wear the engine out.

Here's a short list of what will kill this engine and ANY OTHER marine diesel over time:

1. Over loading, over propping the engine.
2. A poorly designed exhaust system.
3. Lack of maintenance of the salt water cooling system
4. Lack of maintenance of the aftercooler.
5. Lousy fuel filtration

I own a pr. of Cummins RECON 370s. I don't expect to wear either one out. If I do I'd buy another pr. without hesitation.

Now on a "new DE build", depending on the length and hull type I'd consider building........?, the engine choice would be a Cummins QSB 6.7 or a QSC 8.3

FWIW, Bill D
 

sevenjohn

Lieutenant Commander
Joined
Jun 9, 2012
Posts
178
Likes
34
Location
groveland
Boat Make
novi
Bill, thanks for that. In answer to your question... yes the boat is in groveland ,ma. I bought an old '78 young bros 33 and basically building all new.Currently the boat is down to a main bulkhead and not much else. The motor and gear is next.
 

WoundUpMarine

Admiral
Lite User
Joined
Jan 1, 2012
Posts
6,555
Likes
5,424
Location
Boothbay, Me
First Name
John
Boat Make
26' Duffy, 23' Seaway, 14' Holland

sevenjohn

Lieutenant Commander
Joined
Jun 9, 2012
Posts
178
Likes
34
Location
groveland
Boat Make
novi
My son is the computer wizard in this operation,as soon as he gets them on the computer it will be posted.
 

BillD

Admiral
Joined
Sep 1, 2011
Posts
7,748
Likes
3,453
Location
Portsmouth NH.. Piscataqua and Merrimack Rivers
Boat Make
27 H&H with Cummins QSB 5.9 480 power

29chawk

Lieutenant
Joined
Oct 26, 2011
Posts
41
Likes
4
Location
se florida
Boat Make
31' morgan
Did the price go up alot in the last 5 years? sware ive read about them for around 14k a few years ago. Still less than a new 4stroke outboard these days
 

OLD BAY

Rear Admiral
Lite User
Joined
Aug 25, 2012
Posts
1,099
Likes
829
Location
Annapolis, Md
First Name
Eric
Boat Make
Shelter Island 38

BillD

Admiral
Joined
Sep 1, 2011
Posts
7,748
Likes
3,453
Location
Portsmouth NH.. Piscataqua and Merrimack Rivers
Boat Make
27 H&H with Cummins QSB 5.9 480 power
I installed a reman cummins 5.9 in my Wasque 32 in 2006. It was a great decision for me. The engine is absolutely bullet proof and very simple to work on. Plus it was 7-10 grand cheaper than other options with similar or lower HP. I Love the mechanical fuel injection simplicity. If I ever wear this one out, I would do the cummins reman again. One thing I didn't like about other makes was the very loud turbo whine (even in other Wasques). I have found the cummins to have almost no turbo whine until very high power settings (2600 RPM). The Cummins can take a while to wake up in cold temps. She always does start, but a preheater is a good idea if you plan to use her in winter.

OLD BAY,

From what I've heard from the pros on the 6B the engine was designed to start "cold" down to 15F. I've fired my 370s off below freezing many times (end of season when the marina power is shut off)

I eliminated the pre heater circuits on my 370s when I bought them. Eliminated 50% of the wiring on the engine and saved the alternator huge amperage output swings when the pre heater circuit is working. History has demonstrated that the pre heater circuitry can be "problematic" in the 6B mechanical family of marine engines. Easy fixes if an owner wants or needs the pre heat circuit.

I installed 250W block heaters that are plugged in 24/7 @ the dock.

Great engines!

How many hours on your 220??
 

OLD BAY

Rear Admiral
Lite User
Joined
Aug 25, 2012
Posts
1,099
Likes
829
Location
Annapolis, Md
First Name
Eric
Boat Make
Shelter Island 38

BillD

Admiral
Joined
Sep 1, 2011
Posts
7,748
Likes
3,453
Location
Portsmouth NH.. Piscataqua and Merrimack Rivers
Boat Make
27 H&H with Cummins QSB 5.9 480 power
Thanks for the info on the preheaters Bill. I have an engine heater too to help in the sub-freezing weather.

Mine is the 330B, 300 HP at 2800 RPM. I should have said the 2600 was for high speed cruise and that's when the turbo whine sets in.

My engine is just broken in at 350 hours!

My next project is to figure out how to DIY maintain my heat exchanger. The engine still runs at 180-190max but after 6 years i would like to make sure there's no build up.

OLD BAY,

Cleaning the heat exchanger "while on the engine" is an easy DIY.
Take off both end caps. Use a 3/16" rod (I will double check the diameter needed) to clean the individual tubes, put end caps back on with new gaskets. Pretty easy.

IMO of equal or more importance is doing an aftercooler maintenance/service after six years...yes even with the low hours.

If ya need some info on doing either project just holler !!:D

I'll be doing the heat exchangers and aftercoolers on both the 370s @ end of this season. This is season number 4 for the engines and I'll end up with about 560 total hrs.

Aftercooler maintenance on the 6B/BTA should be done every 4 years regardless of hours.

FWIW, Bill D
 

OLD BAY

Rear Admiral
Lite User
Joined
Aug 25, 2012
Posts
1,099
Likes
829
Location
Annapolis, Md
First Name
Eric
Boat Make
Shelter Island 38
Last edited:
Top Bottom