It connects to the negative terminal on the coil, looks similar to condenser inside the dizzy. can't find any info on it

Hi Kirill,

If your Rolla is fitted with a "points" distributor, then there will always/should be a capacitor or condensor in parallel to the points.

 

Read Primary Circuit paragraph http://classicmechan...3/ignition.html

 

These are normally fitted inside the distributor, or as in most of the Nippon Denso & Bosch dizzies fitted to Rollas, it is attached to the outside of the distributor case, close to the terminal. However, it could be connected to the negative terminal of the coil, which is also connected to the points.

 

This might have been done, because an available replacement was a different shape or size, and couldn't easily be attached at the dizzy. Does you points distributor have a capacitor/condensor at the dizzy ?

 

If the capacitor/condensor was on the positive terminal of the coil, it could well be an interference filter, to prevent ignition interference with the radio.

 

Cheers Banjo

Edited July 20, 201511 yr by Banjo

Hey banjo, my car has this capacitor mounted next to coil and also inside distributer. On photos of other ke55 s I can see they have it to . My problem is weak spark .

If you haven't replaced the one in the dizzy, do so. That condenseor builds up the spark to fire the coil. If that doesn't fix it, check the coil resistance and the leads.

 

As Banjo said, the coil capacitor is for radio noise suppression.

Thanks mate

Weak spark can be caused by several things.

 

Resistance in the primary circuit wiring. If the points are worn or "olde", then replace them. Disconnect capacitor to see if that improves things. If it does, in means it has electrically broken down inside, and should be replaced. Check battery voltage under starting conditions. Battery could be weak and getting old. Check ignition voltage to the supply end of ballast resistor & coil with multimeter, with points open & closed. If the voltage drops substantially with points closed, when current is flowing in primary of the coil, then it could mean a high resistance fuse or wiring on the ignition supply. Could even be the ignition switch. Quick test is to run a temporary "thick" wire from battery +Ve to coil and see if spark improves.

 

On the secondary HV side of the coil thare are lots of things that can break down to the HV, & result in weak spark.

 

Break down on the coil top itself. Break down of HV leads, or O/C HV leads. Break down inside the dizzy cap. Spring & carbon bush in top of dizzy. Very dirty spark plugs. Any thing that fails or has detoriated on the HV side should be replaced.

 

As "Altezzaclub" says, measure the primary & secondary resistances of the coil, or take it to an auto electrician who can test it dynamically.

 

A very good way to find leakage or breakdowns in the HV side is to try & start the car in the pitch dark, or even run it in the pitch dark.

 

You then can clearly see "coronas" of HV break down, dancing over leads etc. that are impossible to see in day light.

 

Hope something in there helps you solve your issue.

 

Cheers Banjo

Edited July 21, 201511 yr by Banjo