MG MGB and MGB GT Tech Talk
My tester came in the mail today and I've just done the test.
the car was cold,well it dosn't start yet (needs a coil),so I turned it over a good 10 times for each cylender.
starting from 1 to 4 in PSI.....
132
138
138
142
now that to me looks quite good,I want the engine out anyway to clean it all down,replace seals etc,but is it worth replacing the rings etc.
L
es, start her up & see what you have to start with (oil & water leaks) Comp. is good. Leave well enough alone!
Looks good I wouldn't touch it unless it's blowing oil through the valve guides.
I guess you could refresh the bearing while you have it out but other than that, if there is no sign of significant oil leaking I would leave well enough alone.
ah now we have a problem,just been out to it to check standard ignition stuff and make sure about the coil and found the ignition light is staying on,I never noticed it before.What made me think the coil was gone is that the spark is very small,but this thing with the light staying on even with the key out of the ignition might be the problem.
when I got the car the battery was dead,I charged it up and put it back in,but everytime I've finished doing a check or whatever I've always disconected it just as a safety precaution,seems that was a good idea!
so now I've got the electrical problem,anyone got any ideas to start on?
See this post. I used the search function. You may need to start a new thread if this doesnt help.
http://www.mgexperience.net/phorum/search.php?1,search=ignition+light+stays+on,page=1,match_type=ALL,match_dates=30,match_forum=ALL,body=1,author=1,subject=1
RS
Les,
when the ign. warnig light stays on, the brown/yellow wire at the generator might have dropt or is broken.
The light must be understood as a balance between the battery and the car's electric system. When the engine is running, it should be off as the generator is charging and the voltage of your battery is equal to the voltage output of your generator at this state.
Ralph
I strongly recommend you try and get it running before taking it apart. That way you can see if you have problems that need to be resolved. It looks like your compression is good, and when you get it running you might find that the oil pressure is good and there are no leaks. Hey, miracles happen! :)
Les,
the pressures look ok. Unless you have a serious smoker when you crank it up, I would not worry about the rings.
On to your warning light - what Ralph says is true - check the brown/yellow wire. Make sure it is not shorted out somewhere (a quick test would be disconnect it from the alternator - if the warning light goes out, it is not shorted). Do you have an alternator or generator? If it is an alternator and the N/Y wire is not shorted, then it is likely a failed diode in the diode pack. A good electrical service shop can test it and advise you. Replacing diode pack is less expensive than replacing the entire alternator.
Good luck.
Pat
Its gone dark now so I'll have to wait till the morning but great information as usual!
I wonder if I'll be able to stump you lot before the end of the restoration,I very much doubt it!
I doubt it. If we don't have the answer, someone's bound to make something up that sounds convincing. :)
Its the alternator!,you were right.
Unplugged the alternator and the light went out.Still won't start though,someone has put silicone leads on an old style coil (brass washer type)so I don't think that helps much at the coil terminal.The car had been standing for years before I got it but I think someone has tried to get it going recently because of a few new prts such as rotor arm and cap so it could be a minefield!,it might have just needed fresh petrol in it before they started.
its freezing today so I'll go through the whole system tommorow.
Derek up North Wrote: