10 replies to this topic

[crazy_yoghurt]

Hi

I have been having a few minor issues with the battery/alternator/ignition on my Mini 25 over the last few weeks which I am trying to resolve before i send her in for an MOT

I have replaced the alternator with a brand new one and have now managed to get the engine to fire up, however I get no ignition/battery light before turning the key. I have no idea if the alternator is actually charging the battery as I have no voltmeter (or any idea how i would use one i'm no mechanic).

I was wondering if anyone has any suggestions before i resort to just letting it go in for the MOT and letting them fix it for me (probably rob me of loads of cash I don't have LOL).

Also I have purchased a powder coated alternator fan from ebay any advice on how to remove my old plain boring one and replace it with the new one would also be appreciated

thanks in advance

[Yoda]

If you have connected it up correctly, then the problem is likely to be a blown bulb or bad connection. In either case, you will not get a charge from the alternator, so this needs to be fixed. You will probably find the old alternator was working but due to this problem you were not getting a charge.

Regarding the alternator fan removal, it just needs the large nut removing from the end of the shaft, then remove the pulley, replace the fan and refit all together again.

[crazy_yoghurt]

thanks for that.

looks like its a garage job then as I'm not that confident on wiring and stuff

as for the fan i guess I'm gonna need a vice or something to hold the fan istelf otherwise it's just gonna spin is that the best way to hold it so i can release the nut?

[tiger99]

I use a Black and Decker Workmate for that. I clamp the pulley between the wooden jaws, nut facing up, and unscrew with the appropriate size of socket. Holding the alternator body so it does not fall to the floor, a few taps with a plastic faced hammer on the end of the shaft soon has it out. With care, the pulley is not damaged.

On the car, you can sometimes undo the pulley nut, using a socket and ratchet, by a quick tap on the end of the ratchet, having first tightened the fan belt more than usual.

[crazy_yoghurt]

Thanks tiger99

looks like i'll be busting out my workmate later on then.

cheers

[dklawson]

As above, the warning light is more than just an indicator, it is part of the charging circuit and must work for the alternator to charge. I know you said you would take this to a garage for correction but if you can access the bulb, replacing it yourself could save you a bit of money.

You stated that you are not mechanical so the following probably won't be much help to you but I am providing it so others searching for similar threads will find the information. If you are unable to hold the alternator pulley to remove the nut, hold the pulley with whatever is available to you (strap wrenches, wooden jaw vises, etc.) Use an air powered impact wrench on the pulley nut. The sudden application of torque typically spins the nut right off. This is one of the few areas where I use an impact wrench as my first choice.

[tiger99]

Doug, you have just reminded me of another trick which sometimes works, by mentioning strap wrenches. Some people have one for removing the oil filter, which may work. But in this case you can sometimes improvise one with an old fan belt (not a good one, it will be damaged) and a piece of tube. You bend the belt back on itself tightly, shove the end through the tube, loop the free part of the belt round the pulley, pull the belt tightly so the tube is forced down almost against the pulley, and anchor the two sides of the protruding belt together tightly (Mole grips may work).

[dklawson]

I like the belt and tube idea! That sounds like a great solution.

[crazy_yoghurt]

thanks to everyone who offered advice

I have replaced the fan (i used the workmate) it was much easier than i expected in the end

I have also after having a little bit of a play around (didn't do much just played around with the bulbs and stuff as advised) I now have an ignition light and everything appears to be working as it should do.

Now just to book in for an MOT and we are up and running.

once again thanks all

Ian

[dklawson]

Excellent on both repairs! You should feel very proud of your work and happy with the money you saved.

[tiger99]

Well done, and I am glad the Workmate idea was successful. They have many uses other than what the inventor imagined.