oil pressure & engine temp when stationary

[Big Bad Wolvey]

hi guys, i've looked through a bunch of threads on the subject of overheating and oil leaks but i cant find the problem that i've got.

when cruising at any speed over 30mph the temp gauge stays in the middle and is fine. the oil pressure gauge moves between being a bit low and just about ok depending on how heavy my right foot is on the gas at that moment

however when i get stuck in a traffic jam, or whatever, and only crawling along or stationary for extended periods, the oil pressure drops right down and the engine temp starts to rise. when i'm stationary i always shift into neutral or parking gear but it doesnt help. i tried gassing it a little, when stationary, and with the increased engine revs the oil pressure increases and the temp gauge starts to go back down to normal again. i'm not too fond of doing this though because i'm aware that i'm probly filling the car behind me with exhaust fumes!!

there is oil leaking from somewhere and i'm sure water is leaking from somewhere too because i get air pockets in the cooling system. the oil leak isnt constant though - when i park up it leaks oil for a few minutes then stops.

does anyone know what the problem is? i thought it might be a blown cylinder head gasket, because it looks as though thats where the oil is leaking from, but i'm not sure and i'd like to find out a little more before i start taking action with a socket set.

[Sancho]

hi guys, i've looked through a bunch of threads on the subject of overheating and oil leaks but i cant find the problem that i've got.

when cruising at any speed over 30mph the temp gauge stays in the middle and is fine. the oil pressure gauge moves between being a bit low and just about ok depending on how heavy my right foot is on the gas at that moment

however when i get stuck in a traffic jam, or whatever, and only crawling along or stationary for extended periods, the oil pressure drops right down and the engine temp starts to rise. when i'm stationary i always shift into neutral or parking gear but it doesnt help. i tried gassing it a little, when stationary, and with the increased engine revs the oil pressure increases and the temp gauge starts to go back down to normal again. i'm not too fond of doing this though because i'm aware that i'm probly filling the car behind me with exhaust fumes!!

there is oil leaking from somewhere and i'm sure water is leaking from somewhere too because i get air pockets in the cooling system. the oil leak isnt constant though - when i park up it leaks oil for a few minutes then stops.

does anyone know what the problem is? i thought it might be a blown cylinder head gasket, because it looks as though thats where the oil is leaking from, but i'm not sure and i'd like to find out a little more before i start taking action with a socket set.

The oil pressure moves around all the time - it should be about a third at idle and about two thirds when you're moving. I don't think you have a major problem there but you should get the leak fixed, obviously. If it's at the top of the engine, it could well be the rocker cover gasket, which is not a massive deal.

Change your thermostat, it could be jammed shut or clogged, and do your radiator cap at the same time. Both are cheap, easy and the most likely cause of your problems. Also have a look along the top of the radiator for any signs of leaks. Check that both your viscous fan and electric fans are working properly.

If you do all that and it still overheats you've probably got a problem with the head.

[nero279]

re: the overheating - I would hazard a guess at the viscous fan coupling being shot or needing new silicone stuff.

I would also suggest getting the coolant checked for combustion gases, to either rule out head problems or confirm an expensive predicament.

[BUSHWHACKER]

re: the overheating - I would hazard a guess at the viscous fan coupling being shot or needing new silicone stuff.

I would also suggest getting the coolant checked for combustion gases, to either rule out head problems or confirm an expensive predicament.

Synthetic or semi-synthetic engine oil will give a lower reading on the oil pressure gauge than normal mineral oil.


Maybe lock the viscous fan so that it's spinning all the time like mine.

[Big Bad Wolvey]

The oil pressure moves around all the time - it should be about a third at idle and about two thirds when you're moving. I don't think you have a major problem there but you should get the leak fixed, obviously. If it's at the top of the engine, it could well be the rocker cover gasket, which is not a massive deal.

Change your thermostat, it could be jammed shut or clogged, and do your radiator cap at the same time. Both are cheap, easy and the most likely cause of your problems. Also have a look along the top of the radiator for any signs of leaks. Check that both your viscous fan and electric fans are working properly.

If you do all that and it still overheats you've probably got a problem with the head.

my oil pressure is below a third when idle and ranges between just over a third - half when moving. i kinda hoped it'd be the rocker cover gasket thats blown, but i'm pretty sure its not cause there is no sign of oil leakage around there. i just came back from town and checked the fans when i parked up. they're all working and there doesnt seem to be any radiator leakage either.

where else is the oil likely to be coming from?

[coolsv650]

my oil pressure is below a third when idle and ranges between just over a third - half when moving. i kinda hoped it'd be the rocker cover gasket thats blown, but i'm pretty sure its not cause there is no sign of oil leakage around there. i just came back from town and checked the fans when i parked up. they're all working and there doesnt seem to be any radiator leakage either.

where else is the oil likely to be coming from?

The oil pressure you discribe is certainly like mine, the oil pressure will rise with engine speed, upto a point there a relief valve will stop it raising too far, conversly worn main & big end bearing will cause a drop in oil pressure, often with a knocking that would increase with engine speed.

I'm pretty sure your oil pressure sounds ok, it will also drop as the temprature rises and the oil thins out.

The most common places for oil to leak is the rocker cover gasket, the cam oil seal and the plug as the very back of the head, (it's like a semicircular bung on the very back of the engine & difficult to see without removing the rocker cover.

I don't know of any other place oil would leak from except the head gasket itself. As nero said a combustion test would be a definitive way to find out. You can get the stuf on Fleabay for about £30

[plumb bob]

It sounds like your probs maybe oil/oil pump related, you need to check/test the operation/efectiveness of the oil and water pumps, to make sure they are ok.

What oil have you got fitted?? & when was it last changed??

Is the idle speed correct?

Flush cooling system and replace coolant.

[Big Bad Wolvey]

i last changed the oil in november, but its looking pretty black and vile right now so i got a new oil filter and gonna do that on the weekend. i also got a new rad cap because on closer inspection the top seal on the old one was split... duh i should have seen that the first time!! so anyway, i'm hoping the overheating was because of air in the cooling system. gonna try bleeding it and get all the air out and see if that fixes it.

apparently the oil pressure is fine, i have fully synthetic oil in there right now but i got some 15w 40 oil for when i do the filter change.

still dont know where my oil leak is, but it seems to be coming from the front of the engine somewhere, so i'm gonna take off the sump guard and have a gander.

thanks so much for all the help so far everyone