10 replies to this topic

[Mini71s]

Hoping someone more knowledgeable can help…

 

I’m trying to start up my engine after a refresh but for some reason I’m not getting a spark to my plugs.

 

With ignition on I’ve checked the coil and coil HT lead by randomly earth-ing the coil negative lead and the coil is working and sending a spark down the HT lead so I know the coils working but I’m not getting the plugs sparking.

 

The leads, plugs, condenser, rotor and cap are all new and the points are opening/closing and correct gap.  It’s a 25D dizzy.

 

I’ve noticed that the condenser wire and negative coil wire are both connected on the same terminal is this correct?

 

If so what do you think is the issue for he plugs not sparking?

 

Photo below of dizzy.

 

Thanks for your advice Jason

 

 

 

 

[unburntfuelinthemorning]

If you have a spark from the coil HT lead when earthing the coil negative terminal but are not seeing a spark at any of the plugs then either the contact breaker is not switching properly or the distributor cap is not distributing the spark to the individual HT leads.

 

The condensor wire and coil negative wire indeed should be connected together.  Are the terminals of these two wires in electrical contact with the contact breaker spring?

[GraemeC]

Long time since I’ve played with a 25D, but I would say the terminals should be in contact with the spring and insulated from the nut and the threaded post. The way you have it they are permanently connected to ground and therefore the the points aren’t breaking the circuit to the coil -ve.

Edited by GraemeC, 29 May 2019 - 09:36 PM.

[Ethel]

Looks like your misplace an insulator,

 

The leads go on the spring side of the white plaggy ferule jobbies so the route to earth is via the points contacts and not the retaining nut.

[Mini71s]

If you have a spark from the coil HT lead when earthing the coil negative terminal but are not seeing a spark at any of the plugs then either the contact breaker is not switching properly or the distributor cap is not distributing the spark to the individual HT leads.

 

The condensor wire and coil negative wire indeed should be connected together.  Are the terminals of these two wires in electrical contact with the contact breaker spring?

 

Looks like your misplaced an insulator,

 

The leads go on the spring side of the white plaggy ferule jobbies so the route to earth is via the points contacts and not the retaining nut.

Cheers for the replies all - I will try moving the insulator and put the contacts on the spring side.

 

thanks again Jason

[Mini71s]

Long time since I’ve played with a 25D, but I would say the terminals should be in contact with the spring and insulated from the nut and the threaded post. The way you have it they are permanently connected to ground and therefore the the points aren’t breaking the circuit to the coil -ve.

Cheers for the reply - I will try moving the insulator and put the contacts on the spring side.

 

thanks again Jason

[richmondclassicsnorthwales]

Do you have the small braided wire which earths the base plates ?

 

This is a small inch and a half cotton braided wire which screws on the base plate to the distributor earth

 

I can't see it on your set up

[Mini71s]

Do you have the small braided wire which earths the base plates ?
 
This is a small inch and a half cotton braided wire which screws on the base plate to the distributor earth
 
I can't see it on your set up

Hi, no there isn’t a wire present on mine - though when i’ve looked at other photos of 25D’s there isn’t one on them I can see?

Should it have one on?

Cheers Jason

[richmondclassicsnorthwales]

Hi 

 

Yes, it was normally a pressed wire against the upper base plate and then connected to the body of the distributor.

 

If you look at the points where the wires join on to the points, just above that almost on the body of the distributor, there is a recess on the distributor body, if you look carefully, you will see it is threaded. it should have a screw in, look in turn 180 degree and you will see the other screw

 

This is to where the wire should attach and it should screw in there from the base plate

 

The lower base plate is secured here by these 2 screws

 

You can connect a lead by putting it under the condenser screw

 

If you earth the top plate with the wire, and put the wire under one of the 2 screws holding the lower base plate, it should hopefully start

Edited by richmondclassicsnorthwales, 30 May 2019 - 05:57 PM.

[Mini71s]

Hi 
 
Yes, it was normally a pressed wire against the upper base plate and then connected to the body of the distributor.
 
If you look at the points where the wires join on to the points, just above that almost on the body of the distributor, there is a recess on the distributor body, if you look carefully, you will see it is threaded. it should have a screw in, look in turn 180 degree and you will see the other screw
 
This is to where the wire should attach and it should screw in there from the base plate
 
The lower base plate is secured here by these 2 screws
 
You can connect a lead by putting it under the condenser screw
 
If you earth the top plate with the wire, and put the wire under one of the 2 screws holding the lower base plate, it should hopefully start

Hi, Got home and checked - there is a little black braided wire at the bottom of the plate to the right of the rotor arm, it was a little hard to see until I got a torch.

I’ve swapped the little plastic insulated washer around so the contacts are under it and touching the points arm and it’s now sparking

Thanks everyone for the advice : )

[richmondclassicsnorthwales]

Marvellous !!