Cat 3116 Diesel engines

Did you buy it yet?

IMO
The 3116s had problems at the start. Cat did fix the valve and head issues but all owners had to fight (and still loose) claims.
Deep and thorough records will be required for me to even come close to the 3116 or 3126s.
The inter-coolers have a couple year service life. If your looking at something with old inter-coolers walk now.
I am feared the life span (and support) of these monsters will be half of the ledgened 3208. I feel Cat has already started to really wind down from this model.
If it's in an old SleRay, don't walk away, run.

Sorry I'm an old puss on this topic. My wife calls me Mr doom & gloom.
Now, you find something with a 34 series in it and I'll dance on the roof fer ya.

What kind of boat are your looking for?

I'd take a 3116 over a 3208 any day. The 3116's have a lot of torque, burn clean, and aren't susceptible to overheating if you don't clean the coolers every 2 years like the 3208. The 3208's may be more durable in the low HP versions than the 3116, but they're certainly NOT more durable in the 375-425HP configurations. The 3116's are fairly good motors if they've had all of the aftercooler/etc. updates.

One customer came in with another boat a few months ago, a 2007 Norseman 480. Nice boat with 8.3 Cummins.

Now, That is an engine not be afraid of. The old mechanical 8.3 are bomb proof. Still supported for a long time to come.
Any of the Cummins 6s are a good engines. Easy and on a whole, not to expensive to work on.

Cummins Remans slip rite in.

Problem with a lot of others boats out there, it's a jungle gym moving around them. Steps up, steps down, down, up just to get from the saloon to wheel house to head.
Worked on a larger American Tug yacht that way. Been on a few Krogens that way.
Every lil area or spot on a different level.

In the winter of 1996 we had our (1985) 40’ Tollycraft repowered with 3116’s and still have the boat and never had a problem outside regular maintenance. Now it is our “northern” boat and lives on the upper Mississippi River (fresh water) so it isn’t what I would call high hours given the length to f the season and the Lock system. But since day 1 the engines have never smoked or smoked very and again no problems.
Maybe we are the lucky ones as you do read horror stories about them on boat engines websites. Oh and we run them 85% on plane and the rest hull speed or idle waiting for the Locks

Wow. Good reports on these blocks.
I luv good news. Maybe a good sign for the OP if service records were kept up on what he is looking for.
My eyes see warm salt water service, all year long.

Our “southern” boats in Naples have been/are Tiaras with Cummins and again no problems with those that would be out of the ordinary for regularly/properly maintained engines.

I believe there were issues with 3116’s that had their blocks cast in the foundry in France, dubbed “the French Blocks”, but it has been years since thinking or researching or looking for issues with the 3116’s. Feel confident in them that much. But fresh water engines lead a charmed life compared to salt for sure.

The French blocks were on 3126's. Not sure if any 3116s had the same blocks or French blocks at all.

I have the 3116's on board. These are only 300 hp but reasonable on fuel. They have been flawless with no smoking or issues in any way. But, then again, I regularly service and maintain including the cooling systems as I would on any boat. Mine are 1995's and I don't recall any problems with this model.

I found this Cat release. I really have learned something here and will recall some of my above comments about a end of support for these engines.

Caterpillar Marine announces upgrades to reman models in commercial and yachting apllications.

Miami, Florida - Caterpillar Marine is pleased to announce upgrades to the Cat® Reman Marine 3116 and 3126 model engines ranging from 300 to 420 bhp for use in both commercial and yachting applications. Beginning mid to late Q2 of this year, Cat 3116 and 3126 Reman mechanical engines will come standard with wiring harness, junction box and associated sensors, for ease of installation.

"We listened to our customers and dealers who gave us feedback that dressing out these models to make them more drop-in ready would save time and money on installations," said Bo Cox, Marketing Consultant supporting Caterpillar's Remanufacturing Division. "This upgrade will reduce installation and labor costs, ultimately saving our customers money. At Caterpillar, we succeed when our customers succeed. We are committed to listening to what our customers have to say and continuously improving our product offerings."

Caterpillar offers Marine Reman products ranging from 300 to 700 bhp; Cat® Reman engines provide maximum value by providing improved productivity and efficiency at a fraction of the cost of new, while reducing impact on the environment.

Cat® 3126 Reman Marine Diesel Engine

As the world's leading remanufacturer of diesel engines, Caterpillar employs state of the art techniques, advanced remanufacturing processes, and genuine Cat parts to return each engine to same as new specifications. "Remanufacturing is more than rebuilding," said David Holt, marine industry specialist for Caterpillar's Global Aftermarket Marketing and Brand Division. "It's returning engines and components to their original performance specifications and latest engineering changes using salvage technologies, strict reuse guidelines, advanced manufacturing systems and unequaled quality control." Restoring original performance is possible since new Cat engines and engine components are built to be remanufactured for a second life.

In addition to offering our customers a more cost-effective product, Cat Reman is also good for the environment. Caterpillar's remanufacturing makes sustainable progress possible every day by reducing waste, lowering greenhouse gas emissions and minimizing the need for raw materials to produce new parts. Cat Reman products are backed by the applicable Cat parts or new engine warranty and by the highly trained team of experts in the worldwide Cat Dealer network.

To learn more and meet the Reman experts, contact your local Cat dealer today or stop by the Caterpillar exhibit #F407 at the Miami International Boats Show or at the Miami Yachts Show on Collins Avenue at exhibit C-13/CC35-37. Both shows will be held February 15 – 19 in Miami, Florida.

February 13, 2018
Caterpillar Marine announces upgrades to reman models by Caterpillar

If it was my dollars on the line, I'd go with an N14 Cummins (bullet-proof), or 6BT Cummins - pre electronics. I have delivered a couple of Diesel Ducks - designed by George Buehler and they are perfect for PNW weather and JD engines hold up very well

Yes, Cummins and Deere I do prefer over Cats & Volvo in the mid to low HP ranges. Bomb proof mechanical fuel injection pumps are preferred to easy self service and continued bomb proof operation.
Sad part, Emissions standards are making non computer or common rail engines forced on us. There is a grey line in there for new builds still using older technology but these grey lines are getting smaller.

Luggers were fine a while ago. Not sure if they are up to date lately. Have not been around one (other than light plants) for a long time now.