Keeping Diesel Engine Warm

[Picinisco]

My dodge dually Cummins engine is very hard to start when cold. At home or camping with hookups I can plug in the block heater but what can be done when boondocking.

[Picinisco]

Battery driver side 650CCA reads 690CCA and 3.5 ohms. Passanger side 650CCA reads 190CCA and 13.5 ohms. Proof is in the pudding. Will probaby replace the bad one with another Wallyworld for now befire shelling out for a coulpe of quality ones later.

[Picinisco]

mich800 wrote:
Sounds like something within the starting circuit. You are on the right track. Batteries, cables, ground, starter any or a combination could lead to the slow cranking when cold.

Just bought a Cen-Tech battery analyzer (Amazon $87.42, Harbor Freight $69.99 with coupon $55.99) so will start with the battery condition. Stay posted.

[mich800]

Picinisco wrote:

ppine wrote:
Air filter should not be a problem at all.
The first thin I would check after the battery and starter, would be glow plugs. Any diesel should start easily down to around 25 degrees.

Its a cummins engine so no glow plugs. It has an intake heater. Checked it and its clean and heats up fine.

Problem is slow turning when cold(ish)

Sounds like something within the starting circuit. You are on the right track. Batteries, cables, ground, starter any or a combination could lead to the slow cranking when cold.

[Picinisco]

ppine wrote:
Air filter should not be a problem at all.
The first thin I would check after the battery and starter, would be glow plugs. Any diesel should start easily down to around 25 degrees.

Its a cummins engine so no glow plugs. It has an intake heater. Checked it and its clean and heats up fine.

Problem is slow turning when cold(ish)

[Grit_dog]

^ Although you said it turns over slow when “cold”
Where you’re at, cranking speed between plugged in, hot engine or cold engine should be indiscernible.
How have you verified it’s cranking slow? Presuming you don’t have a reader that shows exact cranking rpms. Have you hooked it up like you’re jump starting it, cold? That’s a way to weed out questionable batteries.
How are all the battery cables and connections? These trucks are voltage sensitive.

[Grit_dog]

Picinisco wrote:

4x4ord wrote:
You shouldn't need much of a battery to start an engine when the temperature is in the 40s or 50s.

You would think so. When on the block heater it starts right up.

That’s because there’s a 90% chance it’s injectors......wish someone had mentioned that earlier.

[ppine]

Air filter should not be a problem at all.
The first thin I would check after the battery and starter, would be glow plugs. Any diesel should start easily down to around 25 degrees.

[Picinisco]

4x4ord wrote:
You shouldn't need much of a battery to start an engine when the temperature is in the 40s or 50s.

You would think so. When on the block heater it starts right up.

[4x4ord]

You shouldn't need much of a battery to start an engine when the temperature is in the 40s or 50s.

[Picinisco]

4x4ord wrote:
If your truck has two new batteries you're likely wasting your money changing them. Your better off spending the money on having a diesel mechanic troubleshoot your problem. There are many things it could be from air in fuel: bad injectors: starter: low compression.... possibly bad batteries or maybe battery connections or cables.....

750CCA recommended for my 2005. "i want to test them with a battery analyzer"

[4x4ord]

If your truck has two new batteries you're likely wasting your money changing them. Your better off spending the money on having a diesel mechanic troubleshoot your problem. There are many things it could be from air in fuel: bad injectors: starter: low compression.... possibly bad batteries or maybe battery connections or cables.....

[zcookiemonstar]

If they are that new You could always try and exchange them at Walmart. I'm sure you don't have the receipt but you never know they may just look at the date.650 ca is what the dealer told me was the replacement for my Dodge about six months ago. I bought some Die Hard batteries so far so good.

[Picinisco]

deltabravo wrote:

Ditto on both of the above.

Does it crank over fast and just not start, or does it crank slower like the batteries have low voltage?

I've dumped the K&N. I've taken the heater apart and it was squeaky clean.

The batteries although 13 months old are cheap Wallyworld issue but are 650CCA.

When the engine is cold it cranks slow so i want to test them with a battery analyzer and change them to Interstate 800CCA from Costco $94.

[deltabravo]

And there is your problem. K&N is the absolute worst air filter there is. Even lightly over oiling it will kill your grid heater in a hurry. Not to mention loss of fuel economy and allowing more dirt into the motor. Your just asking for problems. Take it out, go buy a quality paper filter, clean the grid heater and see what happens.

BTW, I would dump the K&N. They are notoriously bad on turbo diesels and may actually be the problem. The oil in them fouls the MAP sensor so I would get some sensor cleaner and spray said sensor down.

Ditto on both of the above.

Does it crank over fast and just not start, or does it crank slower like the batteries have low voltage?

[Grit_dog]

Picinisco wrote:

zcookiemonstar wrote:
Do you only have this problem when boondocking? Are you disconnecting your camper from the truck? If not this could just be a case of you draining your truck batteries with the campers power usage. Does your truck start fine at home without plugging in the heater?

No
Yes
No

I have thrown away the K&N filter and gone back to a paper filter. I have pullet out the intake heater to clean it but it is spotless.

The person i bought the truck from last february had just replaced both batteries, both marked 11/17 so i did not suspect them however on further examiation i find that they are 650cca batteries so suspect that they are a little weak, when cold, at getting the engine spinning to 200rpm, so when i get the $350 plus to replace them I will.

Before you toss $350 at batteries that you likely don't need. (It's possible, but you can get them load tested for free)
Have your injectors tested. You have the classic symptoms of injectors that return too much fuel at cranking rpms, not allowing high enough pressure to fire.
Iirc, your miles and lack of secondary fuel filtration make the injectors even more suspect.
Don't throw away money because you're in denial it could be a more expensive issue.
On the upside, compared to other diesels, Cummins injectors are the least costly and the easiest to replace. And don't buy reman injectors unless you like to gamble with questionable odds, unless you're planning on selling the truck the next day. Then it will s uck for the new owner...