Dozer overcharging. We have a 1972 D4D Cat that is a Mitsubishi/Japan made tractor. It has Mitsubishi electrical/alt/gen on it. While running it today the ampmeter was higher than usually and once I shut her down, I noticed the finals on both sides were wet. After better inspection, I determined that the batteries were boiling and weeping down onto the finals. Any pointers on what I should be looking for or looking at first? Thanks
It would be nice to get a voltage measurement to see what your current charge rate actually is.
I can do that next time I’m over there.
12 or 24V? get the voltage measurement at the batteries before you start, then at the alternator with the key on, engine off. Then at the alternator with engine on. All the terminals on the alternator. If it's 24V, get each battery's voltage also.
Alternator
And here I thought this was going to be a thread about the rate dealers charge!
left batt at rest was 12.66v right batt at rest was 10.71v combined at the switch at rest was 23.2v left batt while running is at 17.35v right batt while running is at 16.75v Napa Commercial Cat size batts. Within 2 minutes of starting it the caps start bubbling. I didnt have a chance to pull the side cover and check at the V at the ALT last time I was over there.
Voltage regulator on back of alternator
I've always heard over 14.5-14.6 volts charging on a 12 volt battery is when you run into problems. It looks like you have 1 bad battery though. I'm not sure if 1 bad battery can affect the charging rate of both batteries?
Yes, one bad battery will cause the good one to overcharge. The water usage will be much higher in the good battery. A voltage drop test on each battery will prove one is shot. A hygrometer will show a bad cell as well if it is not a sealed battery. Cam
I thought you meant Cat were over charging for parts
He has one bad battery, and both being overcharged. This is not just one bad battery causing an issue with the other one.
So an update. I pulled the alt and reg and went to RE electric and they had a hard time figuring out how to test it since they had no drawings/schematic for the old Mitsubishi stuff that was on there. CAT could not get the regulator, NLA with no updated replacement number either. So at RE we stated getting alternators out and eventually we found a new one wire Delco style that was the same exact dimensions on the top and botttom mounts. The cat pulley was the same diameter center hole for the shaft. Also the distance/offset to the front was the same also. It was a perfect fit for the D4D. The part number is 8367N. It’s a pretty common alternator used on many newer trucks and equipment. It now charges at 27.4v and works perfect.
Here is the Alt.
Also tossed in some new Deka/East Penn batteries to hopefully make this a trouble free upgrade for 6-10 years. $600 later, of course! lol A big thanks to the guys at Romaine Electric in Tacoma for their help (again!)
Two more, just because it seems to look better when it’s working properly!
GOOD deal!!! I'll have to make a note of that Delco number....
They're not that bad to figure out, unless they're not working, then it takes a little longer . If you wanted, you could probably find a new regulator online, but the Delco is easier.
Your alt pulley looks worn. Is it not hard on belts?
Seems to work fine.
It may work fine but the point @56wrench was making is that either the pulley grooves are worn out or the wrong belt profile has been installed. The top surface of a new belt installed on a "to specification" pulley should sit at worst flush or even slightly proud of the top of the pulley flange, not lower as your photo clearly shows. The illustration below may help to explain it. As the Chinaman would say - Sum Ting Wong....
What’s the pros and cons of running the belts and pulleys I have?
There are no pros. Potential cons are vibration, rapid belt wear, chances of fan and/or alternator bearing failure, etc, etc. While you're at it you really need to take a good look at the fan and crank pulleys and inspect them for wear.
How would it wear the bearings?
Vibration.
Vibration is easy to see in a set of belts. The only downfall to running worn, smooth, or deeply seated belts is loss of power transfer and heat. We run a sawmill/lumberyard and Ive spent way to much of my life changing belts and sheaves/pulleys. If the pulley shows no sings of the belt bottoming out in the groove, no slippage/loss of power transfer, no additional heat in the sheave/shaft, no cracking, fraying or cupping/deflection, then I will keep running them. Margins are tight these days and profit$ have gone down and belt$ have gone up, lol! I appreciate the concern from you fellas, but the gypo logger/sawyer in me says the belts gotta a few more hours in them, lol
The alt pulley quite often wears the most/fastest because quite often it may be the smallest of the sheaves that the belt/belts run on