Cummins Twin 6BTA'S

[Chitimacha]

I just purchased a 1995 440 DA Searay with the following engines I took it out yesterday and got the below numbers the engines were blowing black smoke which got all over the boat. The port engine was a little sluggish. What can I look for and can these engines get more power



MAKE: Cummins, twin screw. (See observations)MODEL: 6BTA, DR5043RX 5.9
SERIAL STARBOARD: Specification plate missing.SERIAL PORT: 153624
REPORTED HOURS OF USE: Port 1452, Starboard 1462, on meters.

Full Throttle RPM:	Port:	3000	Stbd:	2900	Speed:	27.5MPH
Oil PSI:	Port:	50	Stbd:	50
Coolant Temp:	Port:	185°	Stbd:	184°
Exhaust Temp:	Port:	90.5°	Stbd:	87.2°
Cruise RPM:	Port:	2500	Stbd:	2500		22.5 MPH
Oil PSI:	Port:	50	Stbd:	50
Coolant Temp:	Port:	175°	Stbd:	181° Thanks

 

[BerettaRacer]

Oil press and coolant temps look about right. I've got a pair of those engines with almost 15,000 hrs each, I change injectors about every 12-1500 hrs so you may be do for a change, may clear up that smoke some.

 

[kevin27]

I have the same engines with about the same hours. What HP rating do you have? Your numbers look good. Easy thing to check is the air filter and when was the last aftercooler was take apart cleaned and fully serviced? Then I would look at injectors. A little soot on my hull is normal on mine but not alot of black smoke. That is usally not enough air for the amount of fuel injected.

As far as doing something to get more power from these engines if they are right they should be plenty. Not really something you want to do.

 

[fwebster]

Your boat is a big heavy boat and 300 hp low torque 6BTA's are marginal power for it. Sooting usually comes from overloading, restricted intake air, or a fuel control issue like a bad injector or an injector with a fouled tip (you would likely see tooting on one side only with an injector issue). It is easy to overload these engines in the 440 so be careful if you get consistent sooting at high rpms.

 

[Chitimacha]

Thanks for the replies I will look into all the info giving Thanks

 

[trit21]

Oil press and coolant temps look about right. I've got a pair of those engines with almost 15,000 hrs each, I change injectors about every 12-1500 hrs so you may be do for a change, may clear up that smoke some.

If you are changing injectors every 1200-1500 hrs, you have a problem as injectors should last the life of the engine if all are ok.

 

[1956olds]

Seems your cruise speed could be a bit higher also 2-3 mph anyway how is the bottom and the props?

 

[Chitimacha]

Just put it in the water a month ago the bottom has new paint and the props were inspected and are ok

 

[trit21]

You can go to quickserve cummins site, here it is, https://quickserve.cummins.com , and put that serial number in but I did and it said it was a bad number. ??

 

[Chitimacha]

That is what was on the bill of sale I will look on the engines and see if I can get proper serial numbers

Thanks

 

[Chitimacha]

Here are the engine numbers

Port 45047068
Star 45047143

 

[trit21]

 

[Art]

You can go to quickserve cummins site, here it is, https://quickserve.cummins.com , and put that serial number in but I did and it said it was a bad number. ??

Tom, went to the link, but could not find where you search. Do you have to be a user before you can do a search?

 

[Chitimacha]

well found a few problems that will cause the smoking and overloading checked the injectors and found 1 not firing and rocker arm loose. The fuel will need to be polished also will check the air fuel control for proper setting.

Thanks

 

[trit21]

You do have to sign up (free btw) to do a search and once you do that you get a lot of diagram, part number look ups etc. I didn't pay the $$ to join but I also understand you get even more if you do but with a resource like Boatdiesel not sure I needed it.

 

[Chitimacha]

I want to change out all injectors how hard is this to do and what kind of injectors do I need parts numbers