Grey Motor Condensor

[Burnsy]

I am just running through my electrical system trying to fix a problem and have replaced my leads, this fixed the problem but I am continuing through it doing a bit of preventative maintenance.

I need a new condensor for the coil and have been told that it is a Bosch GB61-c that I need and the coil is a SU12.

Can anyone confirm this as Bosch no longer list pre HD in their parts book.

Also does anyone know the part number of the condensor on the distributor (if in fact the grey has one - I am not at home so can't check) so I can make sure that it is not this one that I have bought?

Thanks,
Burnsy

[craiga]

Burnsy,

The Grey motor definitely has a condenser - of about 18 - 22uF. The condenser is designed to dissipate the energy remaining in the coil after the energy in secondary coil winding has collapsed - the spark has sparked!! It also protects the points from 'back EMF', a phenomenon where energy from the primary winding of the coil flows back across the points and burns them. Best way to tell if your condenser is stuffed is if you are seeing burning on the point surfaces.

The condenser is just a capacitor - so any modern version of the same spec should be OK. One designed for a HK - HQ will be fine.

I did a tech write up for the NSW Club magazine last year about ignition systems - maybe RET could post it up??

Cheers,

Craig

[Burnsy]

Thanks Craig, I do have burning on the points so that is what pointed me to the condensor.  I am now confused though as my Coil has a condensor on the +ve side - is this the condensor I need to change or is there another one on the side of the distributor?  

[craiga]

Burnsy,

The capacitor on the +ve side of the coil is a suppressor for the radio. It is designed to filter out AC voltage a reduce the crackling effect on your radio. It has nothing to do with the burning of points.

You can safely remove it, and will have no resulting effect except noise in you radio - and usually only AM band.

Cheers,

Craig.

[Burnsy]

AM radio station whats that?  I will remove the capacitor and replace the condensor in the distributor with a GB61-c.  Would have looked pretty stupid replacing the capacitor with a condensor

For those who are interested, Supercheap can order these in from Coventrys for $14 (as they no longer stock them)but if you go direct to Coventrys they want $23.

[Dr_Terry]

Hi Guys.

Capacitor & condenser are 2 different names for the same thing.

The one on the +ve side of the coil is for radio noise suppression & the one on the distributor works in conjuction with the points to fire the coil as mentioned.

The only difference between the 2 is their physical layout (to suit their mounting situation) & their actual capacity value (measured in this case in microfarads).

Dr Terry.

[RET]

Craig's article referred to above is available for Club Members from here.