bluedog333

Well-Known Member

• Feb 15, 2025

• #1

Other than a seizes bearing, is there anything else on the alternator that can fail and cause the pulley to lock-up?
I’ve been trying to track down an intermittent engine issue (felt like engine braking + heavy steering) and finally think I’ve found the culprit. The alternator is about 5 years old, Lucas “quality”. Discovery 200tdi.
Ta muchly.

 

tottot

Well-Known Member

• Feb 15, 2025

• #2

The bearing/bearings having partially seized most likely. Was the alternator getting rather hot?

 

kermit_rr

Very

Full Member

• Feb 15, 2025

• #3

I would say yes. If the regulator fails and causes the stator to burn out/melt/fall apart etc then that could cause it to lock up

 

bluedog333

Well-Known Member

• Feb 15, 2025

• #4

tottot said:

The bearing/bearings having partially seized most likely. Was the alternator getting rather hot?

Click to expand...

No hotter than usual, I think. It’s still charging the battery fine, but at the expense of slowing the engine down!

 

bluedog333

Well-Known Member

• Feb 15, 2025

• #5

kermit_rr said:

I would say yes. If the regulator fails and causes the stator to burn out/melt/fall apart etc then that could cause it to lock up

Click to expand...

I’ll probably put a new one on then. I’ll try and repair the current one when it’s not so cold and miserable out!

 

tottot

Well-Known Member

• Feb 15, 2025

• #6

If the regulator fails sometimes the result is an alternator putting out to many volts, end result will be a fried battery. Check voltage at the alternator connection engine running, should be 14. something at most.

 

bluedog333

Well-Known Member

• Feb 15, 2025

• #7

tottot said:

If the regulator fails sometimes the result is an alternator putting out to many volts, end result will be a fried battery. Check voltage at the alternator connection engine running, should be 14. something at most.

Click to expand...

I’m going to do some more investigating tomorrow. I did some readings yesterday - at the battery was measuring 14.5V, at the alternator was all over the shop, couldn’t get any sort of steady and meaningful reading.

 

kermit_rr

Very

Full Member

• Feb 15, 2025

• #8

Do you have an old analogue volt meter? That will give you a better idea than a digital one will

 

bluedog333

Well-Known Member

• Feb 15, 2025

• #9

kermit_rr said:

Do you have an old analogue volt meter? That will give you a better idea than a digital one will

Click to expand...

I do, good shout.

 

kermit_rr

Very

Full Member

• Feb 15, 2025

• #10

I'm sure you know the drill.. check the volts between the +ve and the alternator body, if you can

 

bluedog333

Well-Known Member

• Monday at 07:11

• #11

Problem solved…and it had nothing to do with the alternator!
Long story short, the alternator belt was probably a bit on the tight side, so adjusted that and now it’s fine. The culprit behind all the issues I have been experiencing? The dreaded lift pump!! I chucked my spare new one on and away she went!
Now I’m going to spend the money I had set aside on an alternator on a 12v fuel pump instead!

 

kermit_rr

Very

Full Member

• Monday at 07:22

• #12

That's great!! But now it's on your mind, check the voltage anyways. It should start charging around 14.7v, if it's closer to 13.6 then it's definitely worth replacing the regulator with a new one, if possible. The battery will love you for it