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[ajsphead]

Alternator no longer giving out any charge. I suspect the regulator pack but am happy to replace the whole thing. Is 127K attached to a nice low revving diesel engine near enough to the end of it's service life to justify total replacement ?

[Marks DTM Calib]

No not at all, the only parts that ever need replacing are the reg and occasionally the bearings.

[ajsphead]

Superb, thanks. I will save myself a fairly large sum of money.

[Diamond Black Geezer]

There's a rumour/suggestion going round that PFL alts are more reliable than FL - in this case is it still just these bearings/regulator affair that need replacing? Ta 

[Marks DTM Calib]

I have always found the pre 2002 alternators better than the later ones 

Same applies, the later ones have a different (and more expensive) reg which appears to fail more often.

[Diamond Black Geezer]

Ta very muchly 

Aiming to get a spare alternator, paint it, replace the bits that wear, so I've got an as-new spare to go on when the time comes. Did a test a while back and it's 'getting on', though still within tolerance, so to speak.

[Marks DTM Calib]

If its working then clean it and fit new bearings, job jobbed (and circa £10.....don't buy cheap no name bearings!)

[Diamond Black Geezer]

no point fitting a new regulator feller, then? Just bother with the bearings? One of those 'aint broke don't fix it' things?

[Bigron]

There is no predictable wear rate/MTBF figure for electronc parts, so no point in replacing the regulator "just in case" - a new one could just as easily fail sooner than your existing one, DBG - so no, don't fix it!

Ron.

[terry paget]

Do they have brushes? I am amazed they can turn out 120 amps. The current seems to be generated in the fixed stator coils, the rotor exciting them. Either the rotor is a permanent magnet, or it needs current to it. I wonder how they work?,

[Nick W]

There is no predictable wear rate/MTBF figure for electronc parts, so no point in replacing the regulator "just in case" - a new one could just as easily fail sooner than your existing one, DBG - so no, don't fix it!

Ron.

You could quite legitimately say that of the bearings. We only hear of the ones that have failed, but how many cars get scrapped with an original untouched alternator? Or any other rotating part for that matter. As these cars age we're going to see more parts that used to be considered bulletproof failing due to wear that would previously have been thought of as unusual.

[Diamond Black Geezer]

Indeed Nick. 

Me, now, I have replaced most of my doors, it's literally insane to spend time grinding out rust, welding new in filler, and a repsray, when a new door can be had for £25 or less, and swapped over in a lunchtime(ish) fast forward a few years and someone with a FC Victor would be faced with no other option than the very costly former.

I mentioned a while ago I'll be getting a spare ECU at some point. Met with several replies of 'why?' of course- well, no-one yet knows the true lifespan of these, the Omega being only really the second generation of cars to have such electronic systems. Once they go - poof! Car go bye bye. Unless spares can be amassed. 

Diff mounts anyone?....dun-dun-durrrr!!

[Marks DTM Calib]

Do they have brushes? I am amazed they can turn out 120 amps. The current seems to be generated in the fixed stator coils, the rotor exciting them. Either the rotor is a permanent magnet, or it needs current to it. I wonder how they work?,

Standard alternator setup, chuck a little bit of current (sub 10 amps) through the rotor field winding, lob in some mechanical rotational input and you induce a large alternating current in the stator windings. Rectify it and job jobbed.

Vary the field current to alter the output volts via the regulator.

There are a few tricks, the poles on the rotor are triangular which creates a non sinusoidal current in the stator (its quite square) which reduces ripple.

Thing is that there is no commutation of the field current (its slip rings and brushes) so no arcing and pretty much no wear as a result.

[Diamond Black Geezer]

I was with you all the way up to 'Standard'


 


https://youtu.be/7kgT5WPktIM?t=836

[Kevin Wood]

There are a few tricks, the poles on the rotor are triangular which creates a non sinusoidal current in the stator (its quite square) which reduces ripple.

Ahh.. Always wondered why they are that shape.