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Electrical Problem MRM

I am slowly working my way through the mechanical areas of MRM 300 W the scrapyard special that I bought as a parts donor (but the parts that I want aren't good enough to justify removing-how sad is that?).

Anyway, there is an electrical problem in that the ignition light doesn't go completely out even when the engine is revved.

On turning on the ignition, the light is very bright, then when the engine fires up there is just a very faint glimmer.
Does anyone know what the cause might be ?

I was thinking of taking the Alternator off to check the bushes as a first step.

I think that MRM has been off the road since November 2005 at least that's when the last tax disc expired.So it probably avoided the scrappage scheme through not being MOT'd.

I have sorted the engine and the brakes and it seems OK mechanicallyexcept for the aforementioned electrical problem,a blowing exhaust (Ithink the downpipe is holed) and a waterleak which appears to be coming from the joint of the bottom hose and the waterpump.As the car has the crappy wire clips on the hoses ,I hope that the leak is from the joint and not from the waterpump.Any way, these two problems will be fixed next week.

That'll just !!!! leave the bodywork before I try to get it MOTed.I will post some pictures of the (g)rot areas next week:o

hi john
it probably is the alterator thats at fault as its been standing and the brushes will be stuck,if you put a volt meter across the battery to check charging imput it will verify if your not showing voltage.
good luck

Thanks Steve .will try this next week.

Hi John. Not long after I bought my GT, my ignition light didnt come on when ignition turned on but when engine was running, it came on. We looked at everything, even changing the alternator to no avail. It transpired that one of the 2 little black round boxes (a regulator?) screwed to the drivers side inner wing had gone down. We changed one and job done. They are dated so you can see how old they are.

Good luck with getting the B sorted.

Hi John...I'd certainly start with the alternator..check whether the battery voltage raises to between 13 & 14 volts at 1500 rpm. I have just replaced my V8's alternator as I had exactly the same problem as it is often the sign that it is about to give the ghost up...

Pity you didn't know when the GB for the 65 amp alternator was going although if you want one let me know as I will be ordering some others from the wholesaler to adapt for the V8 so I'm sure that I can get another 1800 at the same price.;)

Good luck and keep us posted

If it ain't broken don't try to fix it as if you do it will definitely break

Just a thought if nothing else solves the problem, if the car has been laid up for a while it maybe just furred up contacts on either the ignition starter switch or the ignition switch relay thats causing a slight current bleed? I think you may find where these are on Bob's circuit diagram he found. Have a look at the condition of them. Sorry I can't tell you where they are as I've never had to find them myself before.
Good luck with getting the car sorted, hope you solve the problem.:)

Thanks to those who gave advice.A new alternator has sorted the problem and a wter pump has sorted the leak.
Cheers John