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Posted: Sun Oct 18, 2009 10:52 pm
by PSL184
Certainly will be the case re the regulator but it's £20 saved if you ever do need it ;-)
Posted: Fri Oct 23, 2009 6:03 pm
by sgray
Hello again..
I took out the dynamo today to change the brushes, but I just can't get it open. My Haynes says to undo the two screws/bolts marked on the picture below.<br>

<br>
but I can't get these to move. Have soaked them in WD40 and tapped them etc but without any success. Even took them across the road to a neighbour whose far more skilled than I am but he couldn't shift them either.
Do I have to give up and replace the dynamo?
Also, and it may be irrelavant, but when I turn the dynamo and look at the brushes, I see one contact moving in and out on every revolution, but the other one is fixed (shown below) - is this normal or should they both move?<br>

<br>
A new dynamo is £54 + vat so not cheap - actually it's almost the same price as the alternator conversion kit - I wasn't going to put an alternator in but maybe it's sensible to do at the same time??
Simon
Posted: Fri Oct 23, 2009 6:07 pm
by PSL184
The screws are the correct ones to remove but they run the full length of the dynamo so the threads are at the other end - WD40 at the top end won't help. If the commutator is moving with ovality then I guess the bush is worn too which is in the top cap bit (once you remove it)....
Posted: Fri Oct 23, 2009 6:08 pm
by bmcecosse
Both brushes need to move - just get on with it - and remove the screws!!!! Try harder!!!!
Posted: Fri Oct 23, 2009 6:32 pm
by LouiseM
just get on with it
Try harder!!!!
You're starting to sound like one of my old school teachers

Posted: Fri Oct 23, 2009 7:03 pm
by Mick_Anik
Big screwdriver...mole grips.....hammer......a strong will to succeed.....
Edit: a screwdriver with a hex at the top of the shaft, just under the handle, and the appropriate spanner would be better than the moles on the handle - I have a chewed up screwdriver for things like this, but you might not want to chew yours up!
Posted: Fri Oct 23, 2009 7:09 pm
by sgray
^*^*&%&%*&*&^*&^!"%^! - ok, will try one more time.
Posted: Fri Oct 23, 2009 7:15 pm
by Mick_Anik
No!
You have to keep trying until you get them off. You will get them off, if you believe that you will get them off.
A bit like in the film Matrix.
Posted: Fri Oct 23, 2009 7:21 pm
by Mick_Anik
But if you don't have the right tools at the moment, maybe better to wait until you have.
Posted: Fri Oct 23, 2009 7:43 pm
by sgray
I will go and see another neighbour tomorrow and look lost! Thanks for the encouragement
Posted: Fri Oct 23, 2009 7:58 pm
by Mick_Anik
Knowing when you need to stop and take stock is one of the most important aspects of motor mechanics! Butchering on in frustration usually ends in mishap.
Posted: Fri Oct 23, 2009 8:14 pm
by bmcecosse
Apply a little heat at the thread ends - at the other end of the dynamo! And Plus Gas - and a big BANG on the head of each screw with a hammer - and a good solid screwdriver with a good blade, and a pair of grips clamped to it's shaft to turn it. They WILL come out.
Posted: Fri Oct 23, 2009 8:17 pm
by Mick_Anik
I think they are made from hardened steel - that's mainly why they will yield, ultimately.
Posted: Fri Oct 23, 2009 8:22 pm
by bmcecosse
And the end casings are made of mush - so be a wee bit careful!
Posted: Fri Oct 23, 2009 9:46 pm
by linearaudio
Surely in this instance, the simplest way is to grip the outer edge of the screw head with the hypothetical molewrench and they will unscrew easily? Always worked for me in the past! Heating and hitting dynamoes??? What bodgery

Posted: Fri Oct 23, 2009 9:57 pm
by Mick_Anik
One can always try shouting at them!
Posted: Fri Oct 23, 2009 10:09 pm
by bmcecosse
The head may just break off the long screw - be aware!
Posted: Sat Oct 24, 2009 7:31 pm
by Mick_Anik
Main item is the right screwdriver. An impact driver with the large bit for big slots is worth a shot. I'd sit the dynamo upright on two solid blocks, get a mate to hold it, and give the beasts a jolly good seeing to!
Posted: Sun Oct 25, 2009 2:56 pm
by sgray
hello all..
I managed to get the screws undone with a baby stilson and the help of my octogenarian neighbour. The brushes were pretty worn and were disconnected from the wires.
I have fitted the new brushes and re-assembled everything, but I'm still only getting 12v at the battery with the engine running and the ignition light stays on. It dims when you rev the engine - does this mean that the dynamo is doing something?
I have changed the control box for a spare one but the readings are the same.
If I connect the -ve battery terminal and the F (centre) connector on the control box I also get 12v - I was getting 4v before I changed the brushes I think.
any other ideas - any way of confirming the dynamo is working?
Simon
Posted: Sun Oct 25, 2009 6:27 pm
by mike.perry
If you remove the dynamo and connect the terminal to the neg term. of the battery and the body to the pos term of the battery (assuming the car is still pos earth), with a pair of jump leads the dynamo should spin. If neg earth connect the leads the other way round.
Did you clean the commutator and pour a few drops of oil into the bronze bush in the end plate whilst you had it apart?
It can be a fiddle getting the tension springs in place and the brushes contacting the armature when re assembling.