Woe Woe and thrice woe!
Discussion
The old Franki Howerd catchphrase that those of a certain age will perhaps recall.
Now, my latest problem with my newly aquired vintage Humber. Recently it has been hiccuping or miss firing at very low revs such as pulling away from roundabouts, it clears when the revs rise a bit and runs smoothly until repeat process revs drop, misfire revs rise and it clears.
I put this down to the carb' problem but it seems I may be mistaken about this. Today I went to start the old girl up, using the crank handle as starter motor is under repair. Nothing from the engine at all, not even trying to fire into life despite my best efforts.
The ignition system has a magneto conversion using a 12v coil through the mag' and a condenser is fitted as well.
Looks like no spark, the battery is well charged. Is it possible the coil and condenser have given up the ghost?
Now, my latest problem with my newly aquired vintage Humber. Recently it has been hiccuping or miss firing at very low revs such as pulling away from roundabouts, it clears when the revs rise a bit and runs smoothly until repeat process revs drop, misfire revs rise and it clears.
I put this down to the carb' problem but it seems I may be mistaken about this. Today I went to start the old girl up, using the crank handle as starter motor is under repair. Nothing from the engine at all, not even trying to fire into life despite my best efforts.
The ignition system has a magneto conversion using a 12v coil through the mag' and a condenser is fitted as well.
Looks like no spark, the battery is well charged. Is it possible the coil and condenser have given up the ghost?
I can't remember if mags have centrifugal weights? could they be stuck? Points gap closed up? Thinking back don't inlet/vacuum leaks show more at low revs? It's usually something simple (my recent woes of fuel starvation ended up being a float sticking fully up closing the needle valve).
Update, our lad had some spare time and worked through the system. Dried out the magneto which had moisture.
Cleaned up all contacts in ignition system.
Set all gaps
Cut back ignition leads to. are fresh contacts
Tried starting the car at each stage, using crank handle and it only started when the whole system had been attended. It's an ex museum car only used two or three times yearly for past decade or two. Still got the original misfire from engine when it's pulling a load at low revs, and seems to be when engine is working temperature. Fitting new coil and condenser today.
Cleaned up all contacts in ignition system.
Set all gaps
Cut back ignition leads to. are fresh contacts
Tried starting the car at each stage, using crank handle and it only started when the whole system had been attended. It's an ex museum car only used two or three times yearly for past decade or two. Still got the original misfire from engine when it's pulling a load at low revs, and seems to be when engine is working temperature. Fitting new coil and condenser today.
Thanks for continued suggestions. Yes fresh fuel in use. Today I fitted the new ignition coil and condenser, started up OK but I conked out on test drive. Now I have long been a car enthusiast so to run out of petrol is unforgivable 
Refuel and see how we get along, not having a fuel gauge is not helpful and I have yet to grade a fuel tank dipper stick. I love vintage cars.
Refuel and see how we get along, not having a fuel gauge is not helpful and I have yet to grade a fuel tank dipper stick. I love vintage cars.
Today I splashed out on some new spark plugs, noticed another step in improvement of engine performance. Nice one Eccles 
Think I will replace all of the plug leads and the lead to the coil, I think the existing leads are old new stock.
The engine still feels a bit flat so thinking perhaps timing is a bit out, that's a job I am definitely not able to do.
Think I will replace all of the plug leads and the lead to the coil, I think the existing leads are old new stock.
The engine still feels a bit flat so thinking perhaps timing is a bit out, that's a job I am definitely not able to do.
crankedup said:
Today I splashed out on some new spark plugs, noticed another step in improvement of engine performance. Nice one Eccles
Think I will replace all of the plug leads and the lead to the coil, I think the existing leads are old new stock.
The engine still feels a bit flat so thinking perhaps timing is a bit out, that's a job I am definitely not able to do.
Does it have advance and retard on the column? Perhaps try with different levels of each to see if it gets rid of the flatness (is that even a word? Think I will replace all of the plug leads and the lead to the coil, I think the existing leads are old new stock.
The engine still feels a bit flat so thinking perhaps timing is a bit out, that's a job I am definitely not able to do.
)eccles said:
crankedup said:
Today I splashed out on some new spark plugs, noticed another step in improvement of engine performance. Nice one Eccles
Think I will replace all of the plug leads and the lead to the coil, I think the existing leads are old new stock.
The engine still feels a bit flat so thinking perhaps timing is a bit out, that's a job I am definitely not able to do.
Does it have advance and retard on the column? Perhaps try with different levels of each to see if it gets rid of the flatness (is that even a word? Think I will replace all of the plug leads and the lead to the coil, I think the existing leads are old new stock.
The engine still feels a bit flat so thinking perhaps timing is a bit out, that's a job I am definitely not able to do.
)I have the same setup on my 1930 Cowley. I developed a miss fire and over several years could not get rid of it. One day it would not start (handle only on this as it is an ex VSCC trial car). By chance I noticed a spark between the magneto body and the engine block. Cleaning up the interface resulted in no more spark there and no more misfire.
The car has been in storage for the last 10 years or so, tried to start it today and no spark. Again, a spark between the mag body and the block. This weekends job is to pull the mag off and clean it up again, and hopefully it will cure it again. Might be the same problem on yours, worth a look?
The car has been in storage for the last 10 years or so, tried to start it today and no spark. Again, a spark between the mag body and the block. This weekends job is to pull the mag off and clean it up again, and hopefully it will cure it again. Might be the same problem on yours, worth a look?
Just to round off the thread, transpires that the ignition timing was way out. My local trusted garage reset the timing for me. All I need to sort out now is the starter motor which has given up, I will send it off for a rebuild. The dynamo and or regulator which are not working and the starter ring which is in need of a new set of teeth!! Love vintage cars!!!!!
^^^^
Thanks, although not quite there yet, i still is refusing to fire up but have ignition OK right through. Almost there though.
Has your car a cone clutch or plate? My own car is cone clutch and was snatching very very badly. The handbook directed me to add some parraffin through a couple of openings, which I did, two lots sprayed in with an old domestic hand spray thing i. Massive improvement in clutch now.
Thanks, although not quite there yet, i still is refusing to fire up but have ignition OK right through. Almost there though.
Has your car a cone clutch or plate? My own car is cone clutch and was snatching very very badly. The handbook directed me to add some parraffin through a couple of openings, which I did, two lots sprayed in with an old domestic hand spray thing i. Massive improvement in clutch now.
Edited by crankedup on Wednesday 12th July 18:58
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