Hard Starting Cummins

[NorthernFocus]

Ohh yea, I'm gonna try this , so if I put in parallel , its starts ? I wouldn't kleep it that way , only to start it after she been sitting for a while .

Seems to have resolved my issues. I should also mention that the power for the ECM on my boat comes off of the thruster bank. So during starting the ECM doesn't see any voltage dip at all. But it's been that way since I've owned the boat. The inadequate starting battery seems to have been my biggest headache.

 

[hughesdave123]

Ohh yea, I'm gonna try this , so if I put in parallel , its starts ? I wouldn't kleep it that way , only to start it after she been sitting for a while .

Seems to have resolved my issues. I should also mention that the power for the ECM on my boat comes off of the thruster bank. So during starting the ECM doesn't see any voltage dip at all. But it's been that way since I've owned the boat. The inadequate starting battery seems to have been my biggest headache.

worked like a CHAMP! fired right up .

1:I put the bank in parallel
2: then put the key in let the CPU boot
3: Crank 1 time
4: engine started

Thanks , I will now put the bank in parallel on first start after its been sitting .

 

[Levitation]

There is a basic fault in the BOSCH ECM programing for starting when the engine is cold. My experience is that once the program sees some combination of sensor readings it goes into a loop and refuses to inject fuel at the RIGHT time. It does inject fuel as we can see the cloud of fuel vapor coming out.
No amount of priming, battery boosters, etc. will make it start until the ECM program manages to exit the faulty loop of code and injects fuel with proper timing. For those for whom using the parallel switch makes it start perhaps the slight increase in cranking speed, or the slight change in battery voltage the ECM sees is enough to get it out of the faulty loop. It doesn't work for me.
A hint to those having a major issue at some remote marina or anchorage. Always have a can of starting ether and learn how to use it on a diesel. Having the engine fire, no matter how briefly, seems to kick the programming out of the faulty cold start loop.

 

[NorthernFocus]

...A hint to those having a major issue at some remote marina or anchorage. Always have a can of starting ether and learn how to use it on a diesel...

Always, on any diesel, this is good advice.

 

[NorthernFocus]

Just thought I'd give an update on this topic. My starting problems appear to be a thing of the past since I upgraded my batteries as previously explained. I winterized the boat early last September and it sat cold and dry from then until last week. With nothing more than a few strokes of the priming pump it fired right up on the first roll. This compared to the past two seasons when I had to resort to starting fluid after multiple failed starts and the infamous white smoking exhaust.

It's a shame Mercruiser/Cummins handled this topic so poorly. These really are nice operating little engines.

 

[Brian B]

...A hint to those having a major issue at some remote marina or anchorage. Always have a can of starting ether and learn how to use it on a diesel...

Always, on any diesel, this is good advice.[/quote

I've used starting fluid on gas engines in the past. What is the proper way to use it on a diesel?

 

[ixlr8]

I've used starting fluid on gas engines in the past. What is the proper way to use it on a diesel?

The best way to use starting fluids on a Diesel engine... is not to. The ethers are highly flammable and can ignite on compression stroke before piston reacts top dead center and it can lead to bent connecting rods. Lots of folks get away with it, but it is not recommended.

 

[NorthernFocus]

...I've used starting fluid on gas engines in the past. What is the proper way to use it on a diesel?

Basically the same. Squirt the starting fluid into the intake when you're trying to start the engine. It should only be used in desperate straights.