| Author | Message | ||
     George Constantine New User Username: theo Post Number: 31 Registered: 06-2012 |
Weak spark on No 3 & 4 A & B bank, also what is the gap on the ignition module on 1979 shadow, please | ||
| Hubert Kelly Frequent User Username: h_kelly Post Number: 405 Registered: 03-2012 |
George, clean the dash pots of carbon buildup (oil same) it may very well solve symptoms? . | ||
| Robert J. Sprauer Frequent User Username: wraithman Post Number: 641 Registered: 11-2017 |
If the air gap was off within the Opus module, it would effect more than 2 cylinders. I would look at the cap and definitly the wires if original. | ||
| George Constantine New User Username: theo Post Number: 34 Registered: 06-2012 |
Hi Hubert Checked the dash pots, they were clean but cleaned them anyway, no change. Robert, I did change over the HT leads and clean rotor and cap etc but no change? | ||
| Geoff Wootton Grand Master Username: dounraey Post Number: 2223 Registered: 05-2012 |
Have you checked for wear in the distributor spindle. | ||
| Larry Kavanagh Frequent User Username: shadow_11 Post Number: 663 Registered: 05-2016 |
Gap at ignition module in UK/Europe designation cars is 0.76mm/0.03". Australia, Canada, Japan & USA gap is 0.89mm/0.036". Use a plastic feeler gauge. Distributor dwell angle @ 1000 PRM should range between 33 to 39 degrees. Ignition timing using 97 octane petrol should be set at 25 degrees BTDC @ 1300 RPM. I generally use 95 octane petrol and set the timing at 25 degrees BTDC at around 1600 RPM and sometimes have to make slight variations to find the sweet spot. | ||
| Larry Kavanagh Frequent User Username: shadow_11 Post Number: 664 Registered: 05-2016 |
Geoff's suggestion regarding possible wear on the distributor spindle could be on the money. Firing order is A1, B1, A4, B4, B2, A3, B3, A2. Your weak spark would appear to be mostly from one side of the distributor cap. If you have a dwell meter you can get the dwell angle reading from the coil and if the reading fluctuates a lot the chances are that there's wear at the distributor spindle. The reading should be fairly steady at about 36 degrees but any number from 33 to 39 degrees is acceptable provided the reading remains steady. | ||
| George Constantine New User Username: theo Post Number: 35 Registered: 06-2012 |
Thank you all for your input. I'll make a few more checks as per your recommendations | ||
| Larry Kavanagh Frequent User Username: shadow_11 Post Number: 665 Registered: 05-2016 |
Or, if you're lucky it might be something as simple as the rotor arm not being seated properly. | ||
| Robert J. Sprauer Frequent User Username: wraithman Post Number: 643 Registered: 11-2017 |
Remove the plastic pick up and check the 3 ferrite bits. Make sure they are not loose and intact. Pertronix is far more reliable than the original circuit board and related parts. Re-set the airgap. |
