New to diesels - where to start?

b_arrington

Well-Known Member
GOLD Sponsor
Feb 21, 2007
3,469
Setauket, NY
Boat Info
Back Cove 37
AB Ventus 9VL
Engines
Cummins QSC 8.3 600
I just made an offer on a boat with Cummins QSB 6.7 power. Being new to to this type of power (coming from a gas engine), what are some good resources to learn about their care and operation?

I like to know as much as possible about my equipment to do my own maintenance, as well as troubleshooting and just general knowledge.
 
I have heard others tout the amazing resource that is boatdiesel.com A basic membership is $25/year. If I had diesels, I would be a member of that site.
 
If you haven't already seen it, another good resource for learning about keeping your fuel 'healthy' is the fuel management thread by Frank W - it's in the tech articles section. Diesel doesn't 'go bad' like gas, but it has it's own precautions that should be taken into account. All easily doable, though.
 
I would also include others at your marina with similar Cummins engines as well as members of the board. BTW< was the offer accepted?
 
I would also include others at your marina with similar Cummins engines as well as members of the board. BTW< was the offer accepted?

I'm in a very small marina. Most boats are smaller and gas-powered, so I don't have a lot of local folks to speak with.

I don't know about my offer. It was being presented to owner by his broker. It wasn't real until I heard that and now I want to barf.

Thanks for the ideas for info!
 
Last edited:
I have heard others tout the amazing resource that is boatdiesel.com A basic membership is $25/year. If I had diesels, I would be a member of that site.

While boatdiesel is still a great resource for Cummins diesels, the true "authority" for Cummins was/is Tony Athens and he now runs his own forum for free and no longer posts anything on boat diesel.

Tony Athens owns/runs sbmar.com, and every one I have dealt with there has been fantastic. Last July I had to replace my DieselView and had issues getting the replacement working, I traded emails with Corey the electronics specialist all the day on July 4th!

The QSB 6.7 is a great engine, like all aftercooled Cummins you need to keep up with the maintenance of the aftercooler especially if run in saltwater. Other than that feeding it clean fuel, keeping up with regular maintenance and propping the boat at or below the rated specs from Cummins it should last long time!

Basic maintenance is oil and filter changes annually, belts and impellers every other year. Only shocks in maintenance may be the amount of oil and the size of the filters which obviously effect cost. I know I was shocked when I first prefilled my oil filter (for an 8.3L QSC) and it took nearly 3/4 of a gallon of oil!

The aftercooler cleaning is mostly labor except for new gaskets. Not sure about the QSB but for the QSC the genuine Cummins gaskets are $500, sbmar.com sells a set for $75. Aftercoolers should be removed, disassembled, cleaned, greased and reassembled every 2-3 years if in salt water.

Is the boat your considering shaft driven or Zues POD?
 
While boatdiesel is still a great resource for Cummins diesels, the true "authority" for Cummins was/is Tony Athens and he now runs his own forum for free and no longer posts anything on boat diesel.

Tony Athens owns/runs sbmar.com, and every one I have dealt with there has been fantastic. Last July I had to replace my DieselView and had issues getting the replacement working, I traded emails with Corey the electronics specialist all the day on July 4th!

The QSB 6.7 is a great engine, like all aftercooled Cummins you need to keep up with the maintenance of the aftercooler especially if run in saltwater. Other than that feeding it clean fuel, keeping up with regular maintenance and propping the boat at or below the rated specs from Cummins it should last long time!

Basic maintenance is oil and filter changes annually, belts and impellers every other year. Only shocks in maintenance may be the amount of oil and the size of the filters which obviously effect cost. I know I was shocked when I first prefilled my oil filter (for an 8.3L QSC) and it took nearly 3/4 of a gallon of oil!

The aftercooler cleaning is mostly labor except for new gaskets. Not sure about the QSB but for the QSC the genuine Cummins gaskets are $500, sbmar.com sells a set for $75. Aftercoolers should be removed, disassembled, cleaned, greased and reassembled every 2-3 years if in salt water.

Is the boat your considering shaft driven or Zues POD?
Thank you so much!

It’s shaft driven. I’ve been hearing some very expensive maintenance stories about the Zeus pods So straight shaft is fine with me
 
Last edited:
quickserve.cummins.com is a useful resource. You need to enter engine serial numbers to establish a free account (used to cost $50/year). Online maintenance, operations and repair manuals are provided along with fault code look-ups and parts references. It can be a little daunting as it seems to be based on 20th century tech but there is a wealth of information there.
 
Man...posting about an offer on a boat before the deal is done is almost as reckless as posting something like "got all caught up on my maintenance, looking forward to a trouble free summer on the water"! ha. :):)

Only kidding of course. I hope your offer/survey/sea trail are all flawless.

One tip now that you'll be a diesel owner - start cataloging some of the myriad of ways you're going to be superior to us poor gassers. Share how they handle around the docks, how fuel efficient they are and how safe it is to run your generator allllllllll nightttttt long. Go ahead, we can handle it :):)
 
Man...posting about an offer on a boat before the deal is done is almost as reckless as posting something like "got all caught up on my maintenance, looking forward to a trouble free summer on the water"! ha. :):)

Only kidding of course. I hope your offer/survey/sea trail are all flawless.

One tip now that you'll be a diesel owner - start cataloging some of the myriad of ways you're going to be superior to us poor gassers. Share how they handle around the docks, how fuel efficient they are and how safe it is to run your generator allllllllll nightttttt long. Go ahead, we can handle it :):)
You had me at "Diesel"
 
I just made an offer on a boat with Cummins QSB 6.7 power. Being new to to this type of power (coming from a gas engine), what are some good resources to learn about their care and operation?

I like to know as much as possible about my equipment to do my own maintenance, as well as troubleshooting and just general knowledge.

I am in Long Island and have the QSC 8.3 540 Motors. I have this motor for about 10 years now. Follow this maintenance schedule and she will never let you down.

Assuming you don't log more than 100 hours in the NE season.
1. Oil change along with filters Annually. Also send your oil sample for analysis and start trending the results.
2. Fuel filters Annually, change Racors and filters on the motor as well.
3. AfterCooler removal, cleaning, and retesting - When you do the after cooler service have the fuel coolers and gear coolers serviced and cleaned. Every 3 years.
4. Coolant change and pressure test, every 5 years.
5. Heat exchanger cleaning, every 5 years.
6. Raw water impellers along with Cams, every 2 years
7. Belt replacement, every 3 years, you can inspect and prolong up to 5 years.
8. Valve lash adjustment, every 5-6 years
9. Transmission gear oil change and filter, every 2 years.
10. And inspect you motor mounts, hoses, fittings, clamps on a regular basis.
11. Inspect the rubber pucks for dust, between the motor and transmission these connect the motor to the tranny. you will see a vent grate on top of the transmission, inspect this for rubber dust. The QSC had many issues with this, not sure of the QSB, but I wanted to note for you.

Your Local Cummins Dealer service is Wesco Marine. Bill and his team are good people and know what they are doing. He has a captains briefing service and will teach you everything about your motors.

Good luck with your purchase.
 
I am in Long Island and have the QSC 8.3 540 Motors. I have this motor for about 10 years now. Follow this maintenance schedule and she will never let you down.

Assuming you don't log more than 100 hours in the NE season.
1. Oil change along with filters Annually. Also send your oil sample for analysis and start trending the results.
2. Fuel filters Annually, change Racors and filters on the motor as well.
3. AfterCooler removal, cleaning, and retesting - When you do the after cooler service have the fuel coolers and gear coolers serviced and cleaned. Every 3 years.
4. Coolant change and pressure test, every 5 years.
5. Heat exchanger cleaning, every 5 years.
6. Raw water impellers along with Cams, every 2 years
7. Belt replacement, every 3 years, you can inspect and prolong up to 5 years.
8. Valve lash adjustment, every 5-6 years
9. Transmission gear oil change and filter, every 2 years.
10. And inspect you motor mounts, hoses, fittings, clamps on a regular basis.
11. Inspect the rubber pucks for dust, between the motor and transmission these connect the motor to the tranny. you will see a vent grate on top of the transmission, inspect this for rubber dust. The QSC had many issues with this, not sure of the QSB, but I wanted to note for you.

Your Local Cummins Dealer service is Wesco Marine. Bill and his team are good people and know what they are doing. He has a captains briefing service and will teach you everything about your motors.

Good luck with your purchase.
Thanks for the very specific tips! I definitely will want someone to teach me about the motor - sounds very valuable.
 
I'm a very small marina. Most boats are smaller and gas-powered, so I don't have a lot of local folks to speak with.

I don't know about my offer. It was being presented to owner by his broker. It wasn't real until I heard that and now I want to barf.

Thanks for the ideas for info!
But, once you have a diesel boat the sun will shine and birds will sing; people will point and say wow that guy is the real thing....
The stars will twinkle ever much brighter as you know the hardware underfoot is so much tighter.
The rumble and clatter and turbo whine satisfies assurance a destination will be made fine.
So you may want to "barf" and I have no words that rhyme but be comforted that in the end the sun will shine....
Tom
 
Last edited:
But, once you have a diesel boat the sun will shine and birds will sing; people will point and say wow that guy is the real thing....
The stars will twinkle ever much brighter as you know the hardware underfoot is so much tighter.
The rumble and clatter and turbo whine satisfies assurance a destination will be made fine.
So you may want to "barf" and I have no words that rhyme but be comforted that in the end the sun will shine....
Tom

I had no idea diesels were so transformative. Must have been why my dad kept buying diesel cars.
 
b_arrington.....You will do fine. Follow all of the excellent advice you have received on this thread. Not quite 3 years ago, I was in your exact position. Except my boat was an 11' Jet Ski. My neighbor gives me credit for tackling something that big as a move from a jet ski to a 45' boat with twin diesels. Just take it slow. One system at a time. They look big and daunting, but really they aren't. I keep that old expression in mind...."How do you eat an elephant? One bite at a time."

Before you know it, you'll be docking that bad girl in a 15' wide slip, in 20 mph cross winds, fighting a current with a crowd of people at the Tiki Bar watching! Like Stee said, diesels really are the best! ;)

Hope things work out for you.

Jaybeaux

PS...Oil Samples. Blackstone Labs

https://www.blackstone-labs.com/?se...abs.net/Bstone/(S(uaeu1g45zlvab055c25pkgyt))/
 

Forum statistics

Threads
112,948
Messages
1,422,811
Members
60,930
Latest member
Ebrown69
Back
Top