Quote:

---

Fellas -

Excursion didn't want to crank this morning; had to use my jump box to get it going. Has 2 batteries (diesel) and it's a pain to pull them out to bring them to Advance to get tested. Alternator is fairly new (10k miles) and it's been cranking slowly for the past few weeks so I think I'm due a new battery or two.

There's a Harbor Freight in town and it looks like you can get a battery tester for $16 or so. Are these worth a darn? http://www.harborfreight.com/100-amp-6-volt-12-volt-battery-load-tester-90636.html

I don't mind dropping some $ for a nice tester, but there's a Harbor Freight in town and I'd like to get this done today, if possible.

Thanks!

Scott

---

No there not worth a darn. I wanted to buy one from a truck parts supplier and he warned me about them. To get a real battery tester it must put a load on the battery with a heavy duty resister. A good one will cost a couple 100 bucks.

A volt meter will help you decide which battery is giving you trouble. Put the volt meter on the battery and then connect a load to it, like turn on the headlites to check it.

Diesels suck when it comes to batterys because it's usally best to replace both batterys at the same time.

Quote:

---

They are ok. I have used a similar one to that for many years. No, they are not as good as an adjustable carbon pile tester, but you can load the battery with them and they will usually pick out a bad battery. The problem with them is you can't vary the load based on the size of the battery, so they are not real accurate at decerning a "weak" battery from a good battery. The best way to use it is to test a known good battery of the same size ( load it for - say 30 seconds ) and take a voltage reading. Then test your suspect battery and again check the voltage reading after a 30 second load. Anything below 9.6 volts is usually considered a bad battery. Don't forget to start with a fulley charged battery.

---

Quote:

---

This is the one you want. My buddy works for Whayne Supply and has one, he said was exactly like the expensive ones off the tool trucks.

http://www.harborfreight.com/automotive-...ster-91129.html

---

Quote:

---

Both batteries have 13v with no load, 12v with load, and 14v when idling. Both seem to be ok.

Thanks,

Scott

---

Quote:

---

Don't rule out the starter itself. Starters can give an intermittenet draw problem. Some times they start fine, and some times they drag. They can be hard to diagnose, unless they are in the drag mode. When it is in the drag mode, usually tapping on it with a hammer will free it up. Tapping on a starter is not good for a starter. If it's already bad, who cares.

---

Quote:

---

Thanks, that looks like a pretty good deal.

---

Quote:

---

Quote:

---

Thanks, that looks like a pretty good deal.

---

That`s the problem with most of the harbor freight stuff, it looks good but hardly ever holds up. A friend bought a lathe from them and it worked for a few weeks and then broke. They gave him another one and a few months later and it broke again.

---