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Loss of power
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1stpop



Joined: 03 Dec 2007
Posts: 109

PostPosted: Wed Jul 02, 2008 7:04 pm    Post subject: Reply with quote

ARGHHH!!!! its not cured at all!!! but it doesn't happen every time the car is running - just sometimes? any clues?
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pigtin



Joined: 23 Nov 2007
Posts: 1882
Location: Herne Bay

PostPosted: Wed Jul 02, 2008 7:20 pm    Post subject: Reply with quote

Ah! History repeats itself. Confused Have you tried changing the coil and condenser?
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1stpop



Joined: 03 Dec 2007
Posts: 109

PostPosted: Wed Jul 02, 2008 8:58 pm    Post subject: Reply with quote

Its got a new condensor so I will check the coil next...... watch this space. Just thought I've had a couple of times when for no apparent reason it wont start at all - turns over but sounds like no spark!! ha ha - the coil?
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Old-Nail



Joined: 23 Nov 2007
Posts: 854

PostPosted: Wed Jul 02, 2008 9:07 pm    Post subject: Reply with quote

Engine Oil level?
I once had problems similar to this due to the oil frothing and blocking the engine breather, once settled the engine would run normally again. Check there's not too much oil in Confused
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Greeney in France



Joined: 06 Mar 2008
Posts: 1173
Location: Limousin area of France

PostPosted: Wed Jul 02, 2008 9:10 pm    Post subject: Reply with quote

You got it, heat affects the spark as does cold so you may find once started it works at least until the heat builds up and shorts it
I recently changed the coil on my Renault 5 that I have for sale it had similar side effects plus more Rolling Eyes
NEVER trust new condensers always have a 2nd available, in my time of playing with cars and servicing I have had about half a dozen faulty ones
I once had an embarrassing situation too where I service my sister in laws spitfires, it would not start I called the AA out and told him what happened he laughed and cleaned the points with petrol, it started immediately, there was a thin layer of protective gel on the point surfaces to stop damage in transit Rolling Eyes
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pigtin



Joined: 23 Nov 2007
Posts: 1882
Location: Herne Bay

PostPosted: Wed Jul 02, 2008 9:22 pm    Post subject: Reply with quote

As Greeney says, always have a second condenser available, I have recently had two new ones go down almost immediately. If you can get originals they are much more reliable.

Don.
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peter scott



Joined: 18 Dec 2007
Posts: 6299
Location: Edinburgh

PostPosted: Thu Jul 03, 2008 12:14 am    Post subject: Reply with quote

If you're running out of ideas check that the contact breaker plate is making a good earth to the distributor body. The little screws can have stripped threads in the casting.

Peter
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ukdave2002



Joined: 23 Nov 2007
Posts: 3555
Location: South Cheshire

PostPosted: Thu Jul 03, 2008 8:34 am    Post subject: Reply with quote

1stpop wrote:
ARGHHH!!!! its not cured at all!!! but it doesn't happen every time the car is running - just sometimes? any clues?


I say this every time someone has a problem like this; if you can get the car on a Crypton analyzer 9/10 problems will be diagnosed within a couple of mins.

Failing that as it doesn't occur every time it sound like electrical connection, given you have just done the 12 conversion it would be a coincidence if the 2 were not related, either a component that got replaced; coil, control box, etc, or a connection that was disturbed during the conversion or a problem caused by the conversion.

An example I saw of the latter in a similar case to yours was when the A & A1 terminals were not used correctly on the control box, certain combinations of electrical loads would cause the box to regulate incorrectly, producing a drop in voltage to the coil and then misfire, putting the headlamps on would cause this as could other combinations of load.

If you canít get the car on an analyzer it would be worth hooking a temporary voltmeter up to the coil, and seeing what the voltage is when the problem occurs, anything less than 11.5 V indicates a problem.

In terms of component faults, coil has to be top of the list as itís the one thing in the ignition you would have changed (unless you put a ballast resistor in). Normally coil faults are more predictable and associated with heat and breakdown of internal insulation, but a new coil can have a simple dodgy connection inside which would be intermittent.
The control box has to be a contender (and connections to it) Did you put a new control box on ? and did you set it up? If not would be worth running through the set up process.

I would also be tempted to run the car with all ancillary electrical equipment disconnected at the control box and see if the fault is still there, you will know then if looking for something outside of ignition.

Just following on from Peters comment, I was chatting to the Petronix ( replacement electronic ignition firm) tech guys, they were saying that when customer call up with a problem after fitting one of their kits, its nearly always a bad earth on the dizzy plate.

Rotor arms can fail when they warm up and give exact same symptoms as you describe, you may not see any visible sign of a fault, but when they do fail it tends not to be intermittent, also unless you changed it recently it would be a coincidence if it suddenly failed, unless of course you are getting a higher HT output with the new setup which has triggered some tracking on the HT side?


After you have done all this it will probably turn out to be dirty petrol Mad Shocked Very Happy Wink

Dave
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1stpop



Joined: 03 Dec 2007
Posts: 109

PostPosted: Sat Jul 05, 2008 8:39 pm    Post subject: Reply with quote

Just found a fuse in the lighting system that keeps blowing - could this be effecting I wonder? will soon know - lol
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1stpop



Joined: 03 Dec 2007
Posts: 109

PostPosted: Tue Jul 08, 2008 6:01 pm    Post subject: Reply with quote

well... replaced the coil, fixed the short problem, and.... still not running right!! will keep searching. At least its keeping me off the streets!
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Rick
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Joined: 27 Apr 2005
Posts: 21318
Location: North-west UK

PostPosted: Tue Jul 08, 2008 6:17 pm    Post subject: Reply with quote

and all this is since the 12v conversion, or did it show any signs of playing silly bu**ers beforehand?

R
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Various 1920s-1960s - Austin, Morris, Commer, Dodge etc.
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pigtin



Joined: 23 Nov 2007
Posts: 1882
Location: Herne Bay

PostPosted: Tue Jul 08, 2008 7:18 pm    Post subject: Reply with quote

Check the wiring to the switch and distributor, check the insulation to the points, remember, something that was not quite shorting on 6v will sometimes short when you double the voltage. This theoretically should only apply to the low voltage side but it's quite possible you have also boosted the HT, in which case. Rotor arm Dist cap and HT leads. though I assume you have already changed these.
As Sherlock Holmes was wont to say "Eliminate the impossible and what ever is left, however unlikely, must be the answer."

Don.
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1stpop



Joined: 03 Dec 2007
Posts: 109

PostPosted: Wed Jul 09, 2008 8:09 pm    Post subject: Reply with quote

Yes it was playing silly bggrs before thats one of the reasons I went to 12volts - its wasn't very reliable, But now I've got it to start 1st time every time it wont run - lol. Still its why I bought it... gotta learn sometime.
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Rick
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Joined: 27 Apr 2005
Posts: 21318
Location: North-west UK

PostPosted: Wed Jul 09, 2008 8:18 pm    Post subject: Reply with quote

If this is something that was a problem prior to the conversion, I'd be tempted to go back to first principles, ie check:

- engine: check compressions on each cylinder, the head gasket may be on the way out
- fuel: pump diaphragm, fuel line clear, make sure tank isn't pressurising at all, jets in carb not blocked, mixture set ok? choke operating and closing off ok?
- electrics: sounds like you've checked a lot of this, but double check rotor arm, points, dizzy cap, plug leads (including firing order - 1243 not 1342 as on most cars), coil, condenser, main earth lead from engine to chassis, timing

when problems occur, does the engine fade away & cough/splutter, or cut out sharply?

R
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Various 1920s-1960s - Austin, Morris, Commer, Dodge etc.
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1stpop



Joined: 03 Dec 2007
Posts: 109

PostPosted: Mon Jul 14, 2008 8:34 pm    Post subject: Reply with quote

well.... its just fades away... but when its warmed up it seems to run ok? I think there is a problem with the carb and have managed to track down another one to give that a try. I am also managed to find a kit for overhauling the fuel pump which I think is probably a good idea. As I'm finding out, what one guy thinks is a good repair job may not really be up to standard - lol - and there have been a lot of these kind of 'repairs' done on my pop! Rolling Eyes
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