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Thread ID: 121498	2011-10-28 09:05:00	Borris the Morris: Engine dies after while?	The Error Guy (14052)	PC World Chat

Post ID	Timestamp	Content	User
1240498	2011-10-28 09:05:00	So for those of you who don't know a group of us are working on a circa '57 Morris Minor, its in a bit of a mad way but the engine is great and once we got it running it goes very smoothly. Now all of a sudden it has started cutting out during idle or mild revving, bearing in mind it has no brakes and the area the school has permitted us to drive in is small, the speeds are low so we aren't sure if it cuts at speed or if its just in the low revs. Anyway, we don't have a proper car battery and we are using a 12v motorbike battery atm to get the fuel pump going and the first spark in order to crash start it, it almost always picks up from the first catch and the engine runs smoothly, its not skipping or misfiring. Yesterday however the car started to just die, running fine and then gone, no splutter or anything its as if the key has been turned off, pushing off again gets it to start right back up until it dies again. Towards the end of the day we couldn't actually get it started, it would fire a bit and stop. So far we are not sure what would be causing it. I don't think its a distributor problem since that would probably cause an uneven firing pattern (although someone said it could be the condenser). The fuel system looks good. Morris Minors dont have a fuel filter although the pump has a strainer (which was pretty clean) there is a bit of sediment in the carb float bowl though which could be causing it. Right now I am suspecting the sediment being sucked into carb and cogging up the nozzles is the problem, or possibly a lack of electricity since the battery is weak as it is although the car can usually run under its own generator power, not sure what it could have changed electrically that would cause it to stop working now. Anyone have any wisdom to bestow upon us? Next week ill try borrow a proper car batt and try running with that, and clean the carb. Cheers. TEG	The Error Guy (14052)
1240499	2011-10-28 09:33:00	I do voltage drop test on positive side and negative side with a multimeter for checking high resistance in electrical components, e.g. alternator, starter, fuel pump, etc. The component must be running or power supplied with switch on. However I don't know if it's applicable to generators. Maybe try it. Usually earth side is near or at 0 (e.g. < 0.02V) and positive side maybe < 0.6V. Probe along either side (+ then - side) to see if a high reading exists. Maybe test between battery clamp and it's post for resistance as well. Also, a good battery should read about 12.7 V.	kahawai chaser (3545)
1240500	2011-10-28 10:33:00	One thing that used to crop up with these old cars was the failing of the internal earth wire between the points base-plate and distributor body (was usually a braided wire from memory) This would often cause intermittent misfire's and engine cutting out for no apparent reason. The movement that on the base-plate that the vacum and mechanical advance process produces can make the wire break contact if it's getting frayed etc. Not saying that's what the fault is, but certainly one thing I would look at - had it happen to a few cars in the old days :)	bevy121 (117)
1240501	2011-10-28 18:08:00	I would also consider the battery is getting flat.	tut (12033)
1240502	2011-10-28 18:23:00	At higher revs there will be a higher drain on the electrics. If the generator/alternator is under performing, then the ignition will be relying on the battery to provide sufficient power. Problem is the battery also has limitations, and will get weaker as the running time lengthens. Maybe monitor the voltage across the battery while the engine is given some revs. In a healthy system I wouldn't expect the voltage to drop while the engine speed increases (usually the opposite, with voltage rising when the generator gives more juice). If the voltage is low, and abruptly rises at the moment the engine stops, then you've got a drain on the battery (or lack of generation) causing issues.	Paul.Cov (425)
1240503	2011-10-28 19:33:00	Cheers for that guys, ill run over the electrical system some time next week as its more than likely to be that than anything else.	The Error Guy (14052)
1240504	2011-10-28 20:25:00	In the event of any trouble, Cherchez la Lucas.	R2x1 (4628)
1240505	2011-10-29 20:42:00	9/10 Car engine problems are electrical	Ofthesea (14129)
1240506	2011-10-29 22:15:00	It's not a carb problem is it? The SU's need the correct oil in the dash pot to function correctly, SAE 10 and also the correct jets From memory there is some sort of vacuum system in there somewhere (leak) Remember reconditioning one of these ,there is a piece of reinforced hose between the block and head,got the head on,valve gear to notice the hose missing Still remember that	Lawrence (2987)
1240507	2011-11-05 02:13:00	Three things come to mind: A partial blockage in a fuel hose, flap of rubber inside a rotting hose which was designed for leaded fuel. A blocked vent to the fuel tank. Float needle valve seat loose and lowering the needle against the float.	mzee (3324)
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