MGB-GT question?

[amgrave]

I know some of our knowledgable folk also run or have run a MGB. I have just acquired one and I can't work out what a relay is for and can't find it in the manual without knowing what it's for. It's in the engine bay bolted to the inner wing offside. There seems to be from the bulk head end three in a row a starter relay then the fuse block and next to that is the mystery relay. It's a 1975 model.
I'm a bit disappointed with the MGB forums, not a patch on ours. Any help with this is gratefully received and appreciated.
Andy.

[geoberni]

Assuming it's an original fit item, can you work it out from the wiring colour codes against the wiring diagrams in the manual?
Shouldn't be too hard, I can't imagine there's that many relays on 70s car.

Equally, if its after-market owner fit, it should be easy enough to physically follow, as most people won't disturb the car too much fitting an accessory.

Best of luck.

[alanworland]

Horn relay?
Electric fan relay?
Spot/foglight relay?

Alan

[beero]

http://www.advanceautowire.com/mgb.pdf

These diagrams are very good, you should be able to identify it from the wiring colours going to your relay.
Mines a 72 so probably won't be the same.

[kennatt]

can't remember if any of mine had a relay,but they were all of the 70, 72 era. But if it is still connected,you can check the function..... Hold it while an assistant switches on various electric components,you will feel and hear the relay click,if not then probably been an accessory spot lights or after market electric fan.Is it def. a relay,photo would help.

[geoberni]

can't remember if any of mine had a relay,but they were all of the 70, 72 era. But if it is still connected,you can check the function..... Hold it while an assistant switches on various electric components,you will feel and hear the relay click,if not then probably been an accessory spot lights or after market electric fan.Is it def. a relay,photo would help.

These days you can even get GPS Trackers that pretend to be relays. So if it looks like a modern relay, rather than a '70s one, and you can't find out what it does.... https://www.ebay.co.uk/sch/i.html?_from ... y&_sacat=0

[andy.pointeer]

relay.jpg (316.27 KiB) Viewed 2200 times

Does it look like the photo, this is a relay for a electronic fan control, it has two sets of wires, one to fan and one to control unit in top/bottom hose

Red power feed to fuse

[Blaketon]

The attached shows my mother's 1978 GT engine bay. I haven't got the wiring diagram to hand but I think the one next to the fuse box is the relay for the starter solenoid (The solenoid is on the starter motor) and the front one, with the thick brown wire, is the relay for the radiator cooling fan.

If you are interested in connecting battery savers, without having to lift the back seat all the time or in a battery isolator, let me know.

[amgrave]

Thank you for everyone's replys, sorry I am a bit late responding but I changed my email address last week and it seems to have upset the running of the forum and I got knocked off of it so was not able to reply to posts.
However the answers to my question has assisted in finding out the purpose of the relay, it is for the rear heated screen. Not available now but any relay will do the job and I think I have a spare one somewhere.
So again sorry it's taken me this long to respond and many thanks for your help.