CK5
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jump start
- Thread starter 77_Jimmy
- Start date
MrSchaeferPants
1/2 ton status
You're kinda sol on jump starting in the normal sense. All you can do is disconnect the batteries, hook them up to your jump start vehicle, and let it charge a while, switch to the other dead battery, let it charge for a bit, and hook it back up and try.
OR, if you're able, find two 12v batteries, hook em up series/parallel just like your truck, and try that way.
Unless there's big construction equipment, or some other big rig. Not even sure if tractor trailers use 24v. But all your civillian diesels are still 12v.
Can always switch to a 12v 6.2/6.5t diesel starter, then you're good.
EDIT: And btw, if you have a charger at home, same thing, unhook the batteries, charge them separately.
Only reason the CUCVs, and even HMMWVs are a 24v starting system is because the other larger military vehicles that need a 24v system are that way, and everyone can jump everyone else. Cause Army operators are stupid, which is why they all use a nato slave adaptor so operators can't cross the leads
Sorry, can't help it as a former 63B, you see some crazy stuff happen.
OR, if you're able, find two 12v batteries, hook em up series/parallel just like your truck, and try that way.
Unless there's big construction equipment, or some other big rig. Not even sure if tractor trailers use 24v. But all your civillian diesels are still 12v.
Can always switch to a 12v 6.2/6.5t diesel starter, then you're good.
EDIT: And btw, if you have a charger at home, same thing, unhook the batteries, charge them separately.
Only reason the CUCVs, and even HMMWVs are a 24v starting system is because the other larger military vehicles that need a 24v system are that way, and everyone can jump everyone else. Cause Army operators are stupid, which is why they all use a nato slave adaptor so operators can't cross the leads
Sorry, can't help it as a former 63B, you see some crazy stuff happen.
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You're kinda sol on jump starting in the normal sense. All you can do is disconnect the batteries, hook them up to your jump start vehicle, and let it charge a while, switch to the other dead battery, let it charge for a bit, and hook it back up and try.
OR, if you're able, find two 12v batteries, hook em up series/parallel just like your truck, and try that way.
Unless there's big construction equipment, or some other big rig. Not even sure if tractor trailers use 24v. But all your civillian diesels are still 12v.
Can always switch to a 12v 6.2/6.5t diesel starter, then you're good.
EDIT: And btw, if you have a charger at home, same thing, unhook the batteries, charge them separately.
Only reason the CUCVs, and even HMMWVs are a 24v starting system is because the other larger military vehicles that need a 24v system are that way, and everyone can jump everyone else. Cause Army operators are stupid, which is why they all use a nato slave adaptor so operators can't cross the leads
Actually I have had success jumping a 24v truck with 12v hooked to one battery. It only works if the batteries were weak not dead.
MrSchaeferPants
1/2 ton status
Ya, it can be done, as in it will give it juice. Was this jumper vehicle an older non computer vehicle? It's been a while since I looked it over, I forget how it segregates the power since the rest of the CUCV is still a 12v system. I know my CUCV had a Positive and Neutral bus bar. When I got my CUCV it was all disconnected, stuff missing. So I believe one battery was hooked to the bus bars, that fed the rest of the truck, and the battery cables were series/parallel to the starter.In that case, you could hook jumper cables to the bus bars, think it may only charge one battery, but that could get ya going.
Good call, reminded me of that.
MrSchaeferPants
1/2 ton status
Nvmd, I'm all screwed up, cucvs aren't series parallel, there's only two batteries, they're series.
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So, not good for your batteries, or system but
POS jumper to where the +/- connect on the two batteries, NEG to ground. And I keep second guessing myself. Probably not a big deal for dead/weak batteries you're jumping. I'd have to find a cucv schematic to make sense of it.
Everything I'm reading says the front battery is your 12v supply for the rest of the vehicle.
Trying to get you a 100% for sure answer. Walking Dead is getting in the way.
My main worry using a 12v vehicle (esp computer controlled) is backfeeding 24v into the jump vehicle.. not a big worry if the batteries in the 24v are dead'ish. As IIRC each alt charges one battery each. Short exposure shouldn't hurt anything for a jump, figure your alt in good condition is charging at what 14.4v? Up to 16v, you get into bad overcharging around 18v. So jumping some dead'ish batteries I guess you'd be fine.
Those cables will get warm. Mine did jumping my 12v diesel K5 (parallel both bats were 750a ea) with my wife's 12v truck.
Edit for the 20th time. So all I've read, should be OK hooking up to a battery; pos to pos, neg to neg post. But don't do neg to chassis ground. Why... no idea. Where's one our mad electric gurus.
**************
So, not good for your batteries, or system but
POS jumper to where the +/- connect on the two batteries, NEG to ground. And I keep second guessing myself. Probably not a big deal for dead/weak batteries you're jumping. I'd have to find a cucv schematic to make sense of it.
Everything I'm reading says the front battery is your 12v supply for the rest of the vehicle.
Trying to get you a 100% for sure answer. Walking Dead is getting in the way.
My main worry using a 12v vehicle (esp computer controlled) is backfeeding 24v into the jump vehicle.. not a big worry if the batteries in the 24v are dead'ish. As IIRC each alt charges one battery each. Short exposure shouldn't hurt anything for a jump, figure your alt in good condition is charging at what 14.4v? Up to 16v, you get into bad overcharging around 18v. So jumping some dead'ish batteries I guess you'd be fine.
Those cables will get warm. Mine did jumping my 12v diesel K5 (parallel both bats were 750a ea) with my wife's 12v truck.
Edit for the 20th time. So all I've read, should be OK hooking up to a battery; pos to pos, neg to neg post. But don't do neg to chassis ground. Why... no idea. Where's one our mad electric gurus.
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swap batteries and jump the front one.
ok , heres what happened. changed fuel pump , filter , and rubber lines. unhooked the pink wire layed on the starter for 30 seconds , stopped waited for 2 minutes and repeated to bleed fuel system. hooked up the pink wire truck lit right up. let it idle while i was cleaning up my tools and such. drove it around for about 15 minutes parked shut it off. came out about an hour later to run some errands turn the key and all i get is click. did not disable glow plugs if that matters. so did i run down the batteries , volt gauge is on the white line between the yellow and green. or burn up the starter?
MrSchaeferPants
1/2 ton status
Could be a few things? Check voltage with a multimeter. I'd say do a load test but not many people have the tool. Charge the batteries.
And IMO 30 seconds straight on the starter is way too long. 15 second max is what I was taught, heard, read, and practice.
Your last post, you do all of this after the batteries were already low? Some idle time and 15 minutes of driving isn't enough. Or after you did all the work, was why you posted your original question about jump starting?
When I killed my batteries the other week I had it on the charger pretty much all day (max my cheapo charger does is 6amp) for two 740cca batteries
After when you do get it running, don't forget to check the output voltage on both alternators.
And IMO 30 seconds straight on the starter is way too long. 15 second max is what I was taught, heard, read, and practice.
Your last post, you do all of this after the batteries were already low? Some idle time and 15 minutes of driving isn't enough. Or after you did all the work, was why you posted your original question about jump starting?
When I killed my batteries the other week I had it on the charger pretty much all day (max my cheapo charger does is 6amp) for two 740cca batteries
After when you do get it running, don't forget to check the output voltage on both alternators.
i did not know if there was a problem at all. just trying to see if the batteries are bad or its the starter. I had been using the truck as a daily driver. trying to find out if i ran the batteries low or burned up the starter bleeding the fuel system. when the truck is running the volt gauge is in the green. my first post was to find out which is the problem.
MrSchaeferPants
1/2 ton status
If you're in the green, it may be safe to assume you're charging fine. I like using a multimeter when I have doubts.
Only true way to see if the batteries are bad is a load tester and hydrometer to measure the gravity. I believe parts stores can do a load test, not sure if they use the regular one that looks like a electric stove top coil, or a big computer controlled one that looks like a battery charger.
You can check the starter. Go ahead and charge, or if need be try to jump (keeping in mind the 12/24v stuff that was posted). Hard testing the starter if you're not sure on the condition of the batteries. If you had access to two known good batteries, hooked them up, and bench test the starter.
update , took batteries to autozone , 1 failed the load test. bought a new battery , hooked everything up turn the key and starter goes click. volt gauge is still in the yellow. 1 thing was different there was a continuous clicking coming from the dash firewall area.
have you changed the starter relay under the dash to a heavier duty one?
is the chattering at the top of the dash or at the bottom, if its the top its just the GP relay making noise mine makes it also some times when its sorta low of juice.
is the chattering at the top of the dash or at the bottom, if its the top its just the GP relay making noise mine makes it also some times when its sorta low of juice.
No if its the starter relay your starter wont turn off and it will kill its self until you disconnect the batteries
http://www.steelsoldiers.com/showthread.php?61184-Doghead-relay-mod-on-my-M1028
http://www.steelsoldiers.com/showthread.php?61184-Doghead-relay-mod-on-my-M1028
mines always yellow when i turn the key on because it has to charge the GP's on the cucv's I have noticed its easier to have two new batteries instead of a new one and a old one. it starts better and runs better.
You are always supposed to replace batteries in pairs on diesel trucks.
is this a must just to see if the truck will start?
