A few inexperienced guy questions

[chuckschaeffler]

Hi All,

I’ve been learning a lot from you guys just by reading. Thank you!

My wife and I are sailboat to trawler converts. I guess it’s true that ship happens as we get older.

Our new to us boat was built in 2000 which makes our Cummins 6 BT 5.9 M 220 HP either a 1999 or a year 2000, I’m not sure which. Serial # is 45821769,  Cust Spec 3899096. (this number leads me to believe that the engine is a 99)?

I had heard somewhere along the way that some of the early models of these engines had some type of problem in the timing case or somewhere or another  whereby a gear or something could fall off and cause catastrophic damage. I would like to be sure that my engine is not one of those? If so, I would like to do whatever I have to do to correct that problem before I start to make long offshore runs in this boat.

Another question I have is about the jacket water loop that runs from the engine to the domestic hot water heater. I have added a small hydronic system into this loop for cabin heat. The engine coolant loop now goes through a plate heat exchanger and then to the hot water heater before returning to the engine. I have this system plumbed in such a way that I can either send the engine coolant through my hydronic system heat exchanger, to the hot water heater and back to the engine as described above, or for summer time cruising just through the hot water heater and back to the engine.

My question is. Should their be a problem with either my hydronic system or the hot water heater can I close my valves  and essentially dead head this engine coolant loop or would I need to have a bypass so that it can flow?

I would imagine that for engines that do not send coolant through a hot water heater these ports are just plugged off but see the possibility that a bypass hose could be in place to allow this to flow?

Thank you again for all that you have taught me thus far.

 

Topic

[chuckschaeffler]

Thank you Tony for your reply,

I have read your articles about marine age and many other subjects. Thanks once again. Have already rigged up a fresh water flush system. Have removed both heat exchangers, removed the end caps on the main engine cooler, carefully rodded it out where needed and circulated both with barnacle buster. Replaced all the coolant. Gear cooler had already been changed once. M 71 had been replaced once and the old one still on board. Recently pressed the gear off, disassembled it, changed the bearings seals etc.  Currently replacing entire exhaust system from the turbo to the transom fitting with the exception of the Centek muffler which is in good shape. Riser/shower elbow being made again new at Marine Engine Exhaust of Alabama. Old riser/shower elbow lasted 24 years and 3500 hours and hadn’t yet failed so having made the same. Turbo looks good inside with no corrosion. Have read your piece on marine exhaust systems. Have already installed one of your environment kits for the crankcase vapors.

I’m relieved that the dowel pin issue doesn’t pertain to me but will read everything that I may have missed about the 6 BT on your site. Will also google killer dowel pin to see what I have been unnecessarily worrying about.

When I finish the hydronic system and draw it I will post that and some pictures of the system to see what I may have screwed up.

Your’s and the expertise of many of the people who participate in this group have been a tremendous help to me as I try to bring this boat into good seaworthy condition. Hopefully some day I may have some comments or knowledge to offer in return for all I have gained here but for now I realize that I am quite a novice by comparison.
Chuck

[Tony Athens]

https://www.sbmar.com/articles/learning-your-cummins-marine-6bt-5-9-210-220/

https://www.sbmar.com/tonys-tips/ —  Type 6BT in the search–  quite a few things directly applicable  to your 6BT 5.9

 

Ignore the gear issue—100% NOT really applicable to your engine—“killer dowel pin”  “u-tube” it

 

Rock solid & simple engine with ZERO systemic issues,  EVER.

Weakest points ( like most any engine) :

 

1.Sherwood M71 seawater pump—Replace at 10 yrs maximum if it lives in seawater—No upgrades available

2—Idler pulley—“Tony’s tips” and everything else up front that spins

3.—-Gear oil cooler—If it made it to 10 yrs—replace it

5—Entire seawater system—Learn  about it

4— Learn about “Marine AGE”—you are over 20 yrs in ”salt water”

5—think about Freshwater flushing is you spend a lot of time at the dock—9000 + hours a year vs “time at sea”?

6———-Need good pics  and a diagram of you plumbing for your hydronic system to comment

 

Seaboard Founder & President

[Author]

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