Morris Minor Owners Club

when running from cold its ok. after a short trip the light comes on when ticking over but goes out as soon as the car is on the move ? the P.O. had changed the oil and filter. also no rattels or strange noise from engine. what can it be

It's lowish oil pressure........ You should fit an oil pressure gauge asap so you know what's going on. Do you know if it is 20W50 oil in there - and if the filter has been properly fitted - with spring and pressure plate present and correct? It would probably help to drop the sump and inspect the big-end bearings - a new set of shells may make all the difference. But if the crank is scored and worn , it really will need a regrind - which means engine out. But so saying - with gentle handling the engine will still be good for many a mile as it stands. Is it otherwise ok - running well, no excessive oil consumption ?

hi roy. it makes no strange noises, has fresh oil +filter, only had it on the road today and it runs good. cant say about oil consumption yet. unsure about if its 20/50 oil?

Many many A series engines get damaged bearings, because over the years - the spring and pressure plate go 'missing' from the filter container. Then the filter is doing absolutely nothing - dirty oil circulates, and destroys the bearings and the oil pump. It is the one reason I would advocate the upgrade to the screw-on Mini filter - at least it's fool-proof. The only way for you to know is to drop the filter casing and inspect. May be an idea to change the oil and filter anyway - to flush out all the old , and to be sure you have 20W50 in there. The 20W50 from Wilko is fine - no need to spend a fortune on oil for these humble engines. But it does need to be 20W50, and well filtered.

I would be concerned about the oil pressure light on at tickover on a cold engine. First thing to do is to check the back of the speedo to make sure that the oil pressure and ignition warning lights are in the correct positions.
My oil pressure warning light comes on at 20mph after a run down the motorway but still shows 60 psi when starting from cold.
And the engine rumbles if I don't turn the engine over on the starter before firing up

went for a run and the light stayed on untill it was reving harder is this a major problem ie lots of engine work will remove the oil filter housing and change it for the screw on type. would it be worth flushing the engine before adding new oil and filter??? thanks

mike.perry wrote:I would be concerned about the oil pressure light on at tickover on a cold engine. First thing to do is to check the back of the speedo to make sure that the oil pressure and ignition warning lights are in the correct positions.

do the easy things first- check that they are in the right positions.
long shot, but is the pressure switch on the blink? mine was and was on nearly all of the time, feared the worst, but changed the switch and everything was normal again.

also make sure its 20w50 in the engine, drain the old out and replace, then you know for certain.(what bmcecosse said)

had a look at the speedo. the green/ green yellow was in one of the orange lights(what are they for) so swapped it over. could it be the dynamo then? also it has a black faced speedo with 2 orange lights 1 ignition red and the high beem blue, the orange light on far left doesnt come on at all ??? has got the right speedo?? its a 1965 on a c plate thanks

black faced, then yes its got the right speedo.

one of the lights will be for the useless oil filter blocked light- that won't come on.

im not sure on the colour of the oil pressure light wire , but it think it is green and yellow however if im wrong, im sure that someone will correct me in a minute)

oil pressure-orange
oil filter -orange
ignition-red
high beam-blue

the oil pressure should come on with the ignition, should be above the ignition light, but sometimes they are on the other side( been swapped over in the past) no other lights should come on.

You don't NEED to change to the screw-on filter, as long as the spring and pressure plate are present in your cartridge filter, I actually think it is the better filter! Certainly cheaper to get new filter elements. The problem arises when these parts get 'lost' during a filter change. An oil pressure gauge really would be a wise buy. And maybe a swop to 20W50 will 'cure' it - who knows what's in there right now. By changing the oil now you will effectively be 'flushing' it - since it was supposedly (but WAS it ??) changed by the PO.

Red light = ignition, brown/yellow & white cables.
Orange light above red = oil pressure warning light, green/brown
Blue light = main beam warning light, blue/white
Orange light above blue = blocked oil filter warning light, green/yellow. Should never come on if filter is working correctly and is changed regularly.
If you switch off a cold engine then turn the ignition switch on immedately the engine stops, the ign. light should come on first, then the oil pressure light as the pressure in the engine drops

many thanks to you guys i will check all the wires on speedo tommorow and go from there. will be fitting a spin on on filter later in week so will also be getting the oil changed at the same time

I had this recently as well, my oil pressure switch was on knackered. A new one costs about a fiver and can be changed in a matter of minutes. I would try this before doing all those other things and rule it out.