Hot coil
Hot coil
77 MGB w/Pertronix ignition. I know the coil gets quite hot when running. But should it be hot with just the ignition on? Seems it shouldn't be drawing current so shouldn't heat. What am I missing?
1977 MGB
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Re: Hot coil
How long is the ignition being left on? It's not a good idea to do so as the coil will overheat. If you have to leave the ignition switched on for a long period without the engine running then the feed wire to the positive coil terminal should be disconnected to avoid this happening.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
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Re: Hot coil
How long are you leaving it on for ? If its boiling hot after 2 or 3 mins then that's wrong but if it was left on for hours then it could be expected
1979 MGB GT
2003 MG TF
2003 MG TF
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- Posts: 787
- Joined: Wed Dec 21, 2016 6:07 pm
- Forename: Vic
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- Location: North West Hampshire
Re: Hot coil
When I was trying to get my Land Rover windscreen washer pump to work I had to leave the ignition on for a short period but I didn't think of checking the coil. This has Pertronix electronic ignition fitted too with a recent NGK coil.
Presumably you have the correct ballast resistor coil with an impedance of around 3 ohms. Easy to check with a multimeter.
Presumably you have the correct ballast resistor coil with an impedance of around 3 ohms. Easy to check with a multimeter.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
Re: Hot coil
Thank you all. I do have the correct ballast resistor and the coil gets hot after about 1/2 hour. I'll just disconnect it. That works. And I'll revisit this after fixing other electrical issues. Watch for those threads coming up.
1977 MGB
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- Posts: 787
- Joined: Wed Dec 21, 2016 6:07 pm
- Forename: Vic
- Surname: Butler
- MGCC Member: Yes
- MGOC Member: Yes
- Location: North West Hampshire
Re: Hot coil
A few minutes is ok but half an hour is far too long for the ignition to be switched on without the coil being disconnected.
1977 Stage 2 MGB GT
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine
1975 SWB Series 3 Land Rover with a later 2.5 petrol engine