Hi all

i have a quick question for the group

when my truck is cold, when starting the truck, the starter cranks real weak like a dead battery.

1 battery is brand new, the other is about 1 year old. i did a load test on both batteries and they are ok

when the truck is hot, as in if you drive it for 20 minutes, shut it off, then restart it starts normal, or the starter cranks normal

could this be the sighn of a cps going bad? no check eng lights on

thanks!!!!

 

Your batteries are only as strong as the weakest one. You need to disconnect from each other before load testing. If one is weak, that could be you problem.

 

Check the voltage at the battery while cranking it should be >10.5vdc. When it is cold and the GP's are energized it may be pulling the voltage down close to that.

 

i have one of those portable battery load testers, where it loads for 20 seconds

each one comes up good, also it has new glow plugs and relays

thanks

 

or check you starter, that migh just be a problem, if everything checks good,

 

You might also check your older battery with a hydrometer.. If you don't have one, they are pretty reasonable in price.. Got one from Napa a couple of weeks ago for $18. It might show one cell is bad..

 

You could have brand new batteries and starter..but if the connection between the two arent good then youve got starting issues. Clean the battery posts and the cable ends and try again.

 

battery terminals are clean

but i will check the conection at the starter

 

i'm having the same problem. i changed my oil using delvac 15w-40 dino and it's been in the 20's here in the mornings. it doesnt start on the first try. it always catches on the second start. if i plug her in for 2 to 3 hours it starts no problem.
so i started thinking that the oil is cold and thick and the starter is having problems turning it over. so i tried a few different things to see if i could get her to start on the first try. the last tank of diesel i got i didnt put in any diesel kleen... i wonder if that could be the issue... cold mornings, thick oil, and crappy winter blend diesel.
i turned the ignition on and let it sit there for 30 seconds and listened for the fuel pump to shut off and the GP to heat up. no go. still took 2 tries to get her fired up.
when she starts she runs fine. no wump wump noises. after she's been out on the road for 10 minutes or so she's fine, plenty of power.
now i have 100k on my truck and everything is stock except the 6637 filter i did last month.
it's going to be warming up soon down here in GA so i'm probably not going to swap out oil for 5w-40 syn. i guess i'll do that next winter.
in the mean time i went and filled up with 16oz of DK this afternoon. it's going to be a cold one again tomorrow. so i'll guess we'll find out if its the diesel fuel or not.

thanks
-mike

 

well to continue with my experiment this morning... it was 28 out and the truck was not plugged in. with 16oz DK it started up on the first pull. it cranked slow, but caught after 3 seconds and ran fine.
so tomorrow i'll run the heater for 3 hours and i'm sure everything will be fine.
i'm thinking that it's time to swap out the batteries again.

thanks
-mike

 

It does seem to point that way. What type and size batteries are you using? Have they ever run down on you. It seems that if they die once,(leave lights on, leave switch on, ect), they just don't every seem to recovery completly.

 

one is the still the orignal i guess... i've only had the truck for 6 months. i replaced the right side one in october.

 

I think most have found with our trucks, in most cases, it is better to replace both batteries at the same time.

 

yeah, i found that out after i joined this site... if i only had known then what i know now. but i think it's a combination of the cold weather, weaker 2nd battery, crappy winter blend diesel and the new 15w-40 delvac.
now i'm thinking about switching over to 5w-40 syn. but when it's warmed it, it runs great.

 

I've always ran Mobile Delvac 15w-40. I have never had any cranking issues, (running issues, yes). I think we are about the same temp or maybe a little colder. I bought the truck new and only replaced batteries once, 2ys ago. I think the 5w-40 may be to thin for our hot summers.