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Alternator rotor stuck fast

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69 Commando. Stripping clutch cover side for engine removal. Looks like a replacement alternator rotor. Stuck fast. Tried a small 2 arm puller and two screwdrivers behind it but no luck. Very little gap between the rotor and the triple sprockets and chain.

Suggestions welcome

Many Thanks

Eddie Cross

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Evening Eddy

Can you get the triplex chain off? Does it have a split link? one of the links at the top near the clutch chain wheel is a different colour, sometimes meaning a split link, the clip might be at the rear of the chain next to the inner case. Use a mirror to check. If no split link try moving the box towards the engine, possibly getting more space by removing the top and bottom g/box bolts, the movement limited by the inner primary case. If you do get the chain off, it will give you more space to get a bigger/better/three leg puller in there. Report back please   

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Not original rotor and looks like the chaincase was fitted more recently than 1969, so unlikely to be rusted on. Warming rotor to 100C (spit test) ought to give your small puller a fighting chance.

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Thanks Stan and Peter,

Broke out the heat gun this morning. Hot enough to move it out an 1/8" with two screwdrivers before it jammed again but just enough room to give my puny 2 jaw puller a fighting chance.

Now out. Inner crankshaft sprocket knew the game was up and came off easily with the sprocket puller.

Onwards upwards and outwards!

Cheers

Eddie Cross

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Above result very good. Well done all participants. I must question one point, the rotor is said to be a 'replacement' rotor. The number on it is a good number. But the real Lucas disappeared in the 1980s. So this looks like a later 'copy' replacement. Very fine if it does the job but in the 1970s there was lot of failed rotors from Lucas. Can we be sure the replacements are up to the job? Let us be aware. Even advise me if any problems, I am happy to be told of any issues.

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Will do Alan.

Regards

Eddie

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The Wassell/Lucas rotors are constructed in the same way as the ‘welded’ Lucas rotors were. 

 

As you know, they are not welded at all - this was a marketing ploy at the time.

 

However, the laminated ‘keepers’ that cover the magnets are cast in, so nothing can fly off.

 

One thing to be aware of though is the fact there is less clearance (air gap) between rotor and stator with the newly manufactured kit.

It makes good alignment even more critical than it used to be.

 

I take a light skim on the lathe when I use a modern replacement:

https://youtube.com/shorts/OULRRNfaRpE

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Hi Grant,

If I need this done...What amount would I tell my friendly engineer to take off or is he ok with "light skim"?

Thx

Eddie

 

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The official clearance is 8thou. All the way round! Then of course eccentricity is to be attended to. You are working towards this 8 thou, so you can decide what to remove to get this. If the gap gets a bit bigger you will lose a 'very little' electricity.

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Thanks for the information Alan. I will recheck clearance on reassembly

 

Eddie

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Refitted Rotor and 8 thou average clearance to stator. Bit tight in places but feeler gauge clears so will leave as is.

 

Thx

Eddie 

 


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