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MG MGB Technical - wiring loom

I bought a 1977 American mgb roadster abandoned project car. At the moment I am inspecting the condition of the wiring loom and I remove all the wiring that I don't need(seatbelt module,anti run on,...)So I came to the cooling fans wiring and I found a ... between the fuse box and the thermostat. According to the autowire schematics it should be a fuse or a circuit breaker. Can anyone give me some info about that part(Amps rating and so on).
Second question. There should be a "EGR service counter and lamp"according to Autowire. Can anyone tell where should search for that lamp?
H. Jorens

The thermal cut-out looks a bit like a 2-pin indicator flasher. Moss.com have them in stock https://mossmotors.com/circuit-breaker and the markings on the can indicate it is 20A. A fuse would be a standard 17A rated 35A blow, but with the current from twin fans the fuse holder can over-heat and even melt, as I've found with the twin fans on my V8.

According to Clausager the EGR service interval counter was deleted for the 77 to 80 model years. The box is indicated in the attached, the warning light was rectangular and fitted under the cigar lighter.

If you remove the anti-runon system or interfere with the emissions plumbing in any way you are quite likely to find you cannot turn the engine off with the key. This was due to a wiring design error that wasn't initially discovered as the anti-runon system did such a good job of stopping the engine by sucking the fuel out of the car jet. There are various frigs to get round it but to do the job properly as the factory eventually did you will need to move the white/brown wire that feeds the ignition coil from the fusebox to connect to the white wire on the ignition relay. More info here http://www.mgb-stuff.org.uk/fueltext.htm#runonna and scroll down to 'March 2019'.




paulh4

Paul,Thank you for the answer.The original fans are for the garbage bin, instead I will install two 9" fans, they are 80W each. I intend to put a relay in the fan circuit and give the fans a fuse from a new to install extra fuse box.
All the emission things will be removed and I will install two SU's.
When I was looking at the wiring diagram I saw that there was something wrong with the ignition system. But I intend to convert the ignition system a non ballasted system with a 45D dizzy and electronic ignition module inside(I am an Accuspark fan). My other cars(A & BGT) have the same ignition set up and it works perfect. Keeping things simple.I will read your article in Hammer and Spanner and adapt the wiring.
H. Jorens

I'll just say that a ballasted system does have benefits over a non-ballasted for starting in adverse conditions and has no down-sides that I'm aware of.
paulh4

This thread was discussed between 11/10/2019 and 12/10/2019

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