It all started when my vacuum pump pulley seized up last week, I was about 45 miles from home, so I cut the belt off (which had already broken and got wraped up in the pulleys) and was able to drive home at about 40 miles an hour. This kept the engine cool because the fan was able to tun freely.

I replaced the vacuum pump and a new belt, two days later. The batteries were dead (from driving home without a charge), I was able to put a charger it and it started just fine in about an hour. I drove it that day (yesterday) for about 8 hours, stoping and starting numerous times. All was well.

This morning the batteries were dead and when I turned the key on, the dash lights, gauges and WTS lights would come on for about 1.5 seconds and then cut off for about 1.5 seconds, then repeat. I charged the batteries and it is still doing the same.

The batteries most likely need to be replaced, but that should not cause the on and off and on again power.

Could this be the voltage regulator (on the passanger fender) or the regulator that goes to the glow plugs and fuel injectors. Seems like perhaps the main regulator because it is causing all powe to go off an on.

Any and all suggestions would be appreciated!

-Rick

 

You can have the alternator tested at most parts places . How old are the batteries ?..They can be tested also ...

 

Thanks Action - the batteries are probable 3-4 years old. I will replace them. Alternator showed charging all day yesterday. The problem right now is that the batteries are showing a full charge (after charging all morning), and when i turn the key on, the dash lights, gauges and WTS lights will come on for about 1.5 seconds and then cut off for about 1.5 seconds, then repeat. Power will not stay on, seems like a regulator or something cutting in and out.

All suggestions welcome.

 

You may want to clean & tighten all the battery connections & grounds, all the way down to the starter . Sounds like low battery voltage to me ..

 

OK. I will trace all leads in the morning. Battery connections, voltage regulator connections and glow plug regulator connections are all tight.

Have you ever heard of a voltage regulator cycling on and off like i described?

 

The voltage regulator is built into the alternator; it's not mounted externally.

 

Ok, that is good to know. Any ideas as to what would cause the power to cycle as described?

"when i turn the key on, the dash lights, gauges and WTS lights will come on for about 1.5 seconds and then cut off for about 1.5 seconds, then repeat. Power will not stay on, seems like a regulator or something cutting in and out."

-Rick

 

Will a soleniod switch or an ignition switch do this?

 

The only solenoid in play is the starter solenoid (and the one on the fender is the RELAY, it's NOT a solenoid). If this is happening with the key in RUN but not START, it could be the glow plug relay, or just weak batteries. It could be the GPR is pulling so much current that it's pulling down the batteries, voltage is dropping below the point that the relay (or, for that matter, the relays in the underhood fuse box) can no longer energize, then with everything off, the batteries recover, re-energize the relay, and the cycle starts all over again.

How powerful a charger do you have? Is it one that has a "fast charge / jump-start" setting, like 50A or more? If so, try hooking it up in that mode, and turn the key to RUN, and see if it cycles as you describe. If so, then the batteries and/or battery terminal connections are suspect.

Do you have a battery load tester? If so, you should test each one individually. Even if you're simply testing battery voltage, make sure you do it with the two batteries disconnected from one another.

 

Makes sense. I just pulled both batteries out and am hooking them up to the charger, initally one appears to be full charged and one appears to be about 90%.

I do not have a load tester, so will have to take these to Autozone or somewhere to load test.

I do have a 50A / start selection on my charger. After topping off each battery, I will try what you suggested.

Thanks for your suggestions. I will post back with progress later today.

 

Just wanted to close this out. Replaced both batteries and all is fine. Went with Duralast Gold 850 CCA. Thanks for the advice