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Technical Project Paolo

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Technical Project Paolo

Vitesse said:
Does the ignition switch spring back? You should have the off position at 12 o'clock where you can pull the key out. One turn anti clock to parking lights where you can pull the key out. Then one turn clockwise which turns on all the ignition lights etc, then another turn clockwise which should be sprung which is where you turn the starter over. I've got an original 850 ignition switch here and the springy bit is very sprung but this is a brand new switch.
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Yes its a sprung ignition switch and the key is springing back but the starter still turns. Even when I turn it to off!
 
Will try it tomorrow when I have an assistant. I guess if the voltage stays at 12v its the switch and if it drops to 0v its the starter?
 
Sounds like the solenoid is getting jammed on. You can take it apart, it's just a magnet and a coil but it might be a bugger to get to with the engine in situ.
 
If its the starter- give the solnoid a "persuader" tap.....the contacts may of fused together.
 
AndrewHarvey said:
If its the starter- give the solnoid a "persuader" tap.....the contacts may of fused together.
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Just tried that Andrew but it still spins. I have two starters and have just bench tested the other one which works perfectly. Have a feeling the one I have on the car is dodgy. Will swap them over tomorrow and fingers crossed that will fix it.
 
A bit of success, the starter was dodgy. Swapped it with my spare and it now only spins when you turn the key to the start position. However I now cant get the engine to fire. Here starts the usual sequence of trying to find the culprit!
 
Need some electrical help please. Have established that I am getting no spark at the plugs. I am running a hall effect sensor so no points or condensor so the next thing back is the coil. Had the wife turn the key whilst I had the voltmeter on the coil + & - . Got no reading. Took the wire off the positive terminal and connected that to my voltmeter and put the negative on the coil. Turned key and got 12.6v. So it seems that the coil is at fault but I have tested the primary resistance and got 3.4 ohms and get 11000 ohms on the secondary. What am I missing?
 
Paolo66 said:
Need some electrical help please. Have established that I am getting no spark at the plugs. I am running a hall effect sensor so no points or condensor so the next thing back is the coil. Had the wife turn the key whilst I had the voltmeter on the coil + & - . Got no reading. Took the wire off the positive terminal and connected that to my voltmeter and put the negative on the coil. Turned key and got 12.6v. So it seems that the coil is at fault but I have tested the primary resistance and got 3.4 ohms and get 11000 ohms on the secondary. What am I missing?
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Hi Damian you won't get 12v across the coil when the terminals are connected. It is after all what it says it is, a coil of wire connecting the two terminals together, that measures 3.4 ohms in resistance. It's exactly the same as you putting + 12v's on the end of a bit of wire. Then sticking your meter on each end of the wire.

You need to measure the + terminal to earth and - terminal to earth it will be the same, as the voltage drop across the coil resistance 3.5 ohm is so minimal you won't see it.

Remember the black wire of the coil - goes to an insulated little plastic terminal post on the distributor to prevent it from earthing. It's the points or the electronic ignition that allow the current to flow to earth.

Can you go back to points and condenser to see if you can get a spark with them?
 
Thanks Tony. Bloody electrics is like voodoo black magic to me. I cant go back to points and condensor. Are you saying my coil is okay? If so is it just timing? I swapped over the leads and still got nothing and also twisted the distributor but still got nothing
 
Paolo66 said:
Thanks Tony. Bloody electrics is like voodoo black magic to me. I cant go back to points and condensor. Are you saying my coil is okay? If so is it just timing? I swapped over the leads and still got nothing and also twisted the distributor but still got nothing
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Yes the coil sounds good from those resistance figures you posted.

I might be wrong as I haven't used a Hall effect for years but I don't think you can manually twist the distributor around i.e. The same as you would when opening and closing points and get a spark on a plug resting on the block? I think the engine needs to be spinning at speed to do that. I know that is the case with the distributorless ignition I have on the 650 engine.

Tom runs a hall effect I think and should be able to clarify?
 
No I meant I'd twisted it in different directions to see if the timing was out but it made no difference as I have no spark at all. That means it can only be coil, leads or rotor doesnt it?
 
Franko500 said:
Do you have a standard dizzy with points that you could try first.
Go back to basics first, get the engine running then you can play with modern stuff
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I might have the bits somewhere but if the leads or coil are at fault the result will be the same surely? The only thing that I dont have a spare of is the coil
 
Just disconnected the HT lead and held it against the engine block. There is no spark so that points to the coil doesnt it?
 
Changed coil, rotor arm and dizzy cap. Got a spark at the plugs now but still wont start. All as I get now is nothing and then a really loud back fire.
 
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