Possible bad alternator

[j_boucher]

So I noticed my voltage was a the bottom of the 28V on my gauge, I went and check the alternator out put and they seemed fine but was curious does the voltage regulator lights blinking on and off green normal or do they need to be steady , no other colors just green , I just took it to the store and noticed my headlight symbol in dash blinking and when I got home I noticed the front lights turning on and off corresponding with the dash light. And now I have no more output from the alternator regulator lights still blinking . Anyone ever seen this ?

 

[Ronmar]

measure the voltage at the alt.

flashing green means it thinks its voltages are normal...

 

[MatthewWBailey]

So I noticed my voltage was a the bottom of the 28V on my gauge, I went and check the alternator out put and they seemed fine but was curious does the voltage regulator lights blinking on and off green normal or do they need to be steady , no other colors just green , I just took it to the store and noticed my headlight symbol in dash blinking and when I got home I noticed the front lights turning on and off corresponding with the dash light. And now I have no more output from the alternator regulator lights still blinking . Anyone ever seen this ?

 

[j_boucher]

View attachment 926445

Thanks I believe it was the grounding strap I cleaned connections on grounding strap, Both 28V and 14V wires and terminals at battery . Seems to be working OK. Thanks for the quick responses greatly appreciated

 

[MatthewWBailey]

Thanks I believe it was the grounding strap I cleaned connections on grounding strap, Both 28V and 14V wires and terminals at battery . Seems to be working OK. Thanks for the quick responses greatly appreciated

Seems like a common problem on a lot of these.

 

[MatthewWBailey]

Thanks I believe it was the grounding strap I cleaned connections on grounding strap, Both 28V and 14V wires and terminals at battery . Seems to be working OK. Thanks for the quick responses greatly appreciated

.

 

[Ronmar]

Thanks I believe it was the grounding strap I cleaned connections on grounding strap, Both 28V and 14V wires and terminals at battery . Seems to be working OK. Thanks for the quick responses greatly appreciated

Have you cleaned the connections on the polarity box/LBCD back by the spare tire? How about ground strap between starter and drivers frame? the alt relies on a good connection between alt and batt, all 3 of them, 12, 24 and gnd…

 

[j_boucher]

Have you cleaned the connections on the polarity box/LBCD back by the spare tire? How about ground strap between starter and drivers frame? the alt relies on a good connection between alt and batt, all 3 of them, 12, 24 and gnd…

Those are on the list today , although I don't remember ever seeing one on the starter will be going out to check soon

 

[Ronmar]

Those are on the list today , although I don't remember ever seeing one on the starter will be going out to check soon

The battery ground lead cable runs to a stud on the front of the starter motor housing. From that stud there is a braided strap over to the drivers frame rail. That is how battery ground reaches the rest of the chassis…

voltage drop tests can be run on all these circuits if you have a battery load tester. the voltage dropped/developed by the wire resistance while feeding a load thru the circuit is a definitive test of circuit capability…

 

[j_boucher]

The battery ground lead cable runs to a stud on the front of the starter motor housing. From that stud there is a braided strap over to the drivers frame rail. That is how battery ground reaches the rest of the chassis…

voltage drop tests can be run on all these circuits if you have a battery load tester. the voltage dropped/developed by the wire resistance while feeding a load thru the circuit is a definitive test of circuit capability…

Yes I found it , already cleaned the connections on the polarity box , curious when the change from being the Polarity relay box went to being the newer LBCD .

 

[j_boucher]

The battery ground lead cable runs to a stud on the front of the starter motor housing. From that stud there is a braided strap over to the drivers frame rail. That is how battery ground reaches the rest of the chassis…

voltage drop tests can be run on all these circuits if you have a battery load tester. the voltage dropped/developed by the wire resistance while feeding a load thru the circuit is a definitive test of circuit capability…

The battery ground lead cable runs to a stud on the front of the starter motor housing. From that stud there is a braided strap over to the drivers frame rail. That is how battery ground reaches the rest of the chassis… ------ Mine has a good amount of rtv type substance on the front of starter " prob for water proof" , beginning to clean all this now

 

[Ronmar]

In place of a rubber cover, the rtv keeps a dropped wrench from arc welding itself in place. Not needed on the ground stud though, only the + terminals on the solenoids and starter motor…

later A1 trucks added the battery disconnect relay and the LBCD to control it/ disconnect the load/batts from an overloaded alt and put them on a trickle charge.

I believe this was a bandaid to protect the alt from the grossly oversized battery instead of upsizing the alt to match the batts. AGM batts made the problem too big to hide with a LBCD, so they finally upsized the alt to a proper size for the batts…

 

[MatthewWBailey]

the rtv keeps a dropped wrench from arc welding itself in place

That's interesting, I thought it was just a crude thread locker to keep that hot lead from coming off and whipping around. Never thought of the wrench risk lol

 

[MatthewWBailey]

LBCD

I gave mine away to a needy family from Ecuador. They had more use for it than I did

 

[Skyhawk13205]

In place of a rubber cover, the rtv keeps a dropped wrench from arc welding itself in place. Not needed on the ground stud though, only the + terminals on the solenoids and starter motor…

it is common to have potting on ground and bonding straps in the aviation world, usually the potting you use is a special type of RTV that is less corrosive, what the potting does best is to hold the water and corrosion in until the connection fails, usually intermittently and at the worst times possible.

 

[Ronmar]

it is common to have potting on ground and bonding straps in the aviation world, usually the potting you use is a special type of RTV that is less corrosive, what the potting does best is to hold the water and corrosion in until the connection fails, usually intermittently and at the worst times possible.

Exactly! I have never seen topically applied RTV seal anything, except the moisture inside the connection

 

[MatthewWBailey]

Exactly! I have never seen topically applied RTV seal anything, except the moisture inside the connection

..that's because it must be administered intra venously otherwise ineffective.