what damage have i done

[james butler]

i went out going to bassets pole last nite, when as i was going down the m42 the alternator belt snapped so while taking it v steady cruised the last half a mile off the moterway and off a junction. battery light was on but the coolant stayed about where it normally does, so i had the bright spark idea of trying to limp it home. i got as far as shirley when the oil pressure light came up on the dash and ide ad enough by then and shut it off. time to call the breakdown cover. but other than the engine seizing why else would the oil pressure light come on as well as buzzing? im going to try a new belt tonight to see if she still runs but when i stopped the coolant had got red hot and boiling in the top half of the engine while the bottem alf was cool so im thinking head gasket will probly have gone agen, but the oil light is the one thats got me worried. because it was the alternator belt that snapped i was running on batt power so could it be lack of power that brought it on (wishfull thinking)? i really ope i havent done anything serious

[ChrisPears]

If the coolant isn't circulating, then the oil could have got very hot and really thinned out since its the only thing cooling the engine. This would result in a loss of oil pressure.

You might get away with it if you shut it off as soon as the oil warnings went off.

[eefy]

i had the same think with my oil light coming on when the oil got very hot, the oil was old and was getting thin, new oil solved my problem.

cant believe your temp light didnt come on with in minutes!!!! when mine snapped i got about half a mile before the engine started overheating, ended up getting a lift backhome on a low loader lol

[Nate]

as said, the oil gets thinner as it gets too hot, so will flow easier making the pressure less. once it has cooled down you will have normal oil pressure return, assuming you didn't try to drive it once the light came on. if you did carry on driving, you may find that it will have low pressure at tickover and may spit a bottom end bearing out at some time in the future. the more likely damage is that you will have warped the head causing a gasket failure

[ChrisPears]

Probably best to change the oil before you try starting it up again....the stuff that got cooked won't be very good anymore.

[james butler]

i shut it off as soon as i saw the oil light come on. yeah it was strange that the water temp light never came on, but as i was trying to drive it i was watching the temp gauge for signs of over heating but it never went above half way???? i gave the car a real good service on saturday the plugs were sooted up and the oil was black but after a good service ive been driving it the last couple of days and it has been fine. a bit ruff for the first 10mins but freed up after a bit. im hoping ive got away with it. cheers guys