Oil Pressure/ Coolant Temperature

[jonathan lovell]

Hi guys,
i have a Year 2000 W reg 2.0 Petrol Bora, the coolant temp gauge never seems to get up to 90 degrees, sometimes it will slowly rise up and then drop back off again. i also wonder if this has anything to do with a oil pressure low alarm i get sometimes ifit is a cold morning, when i took the oil filling cap off there seemed to be a brownish sludge round the cap, does this mean that i have a possible coolant leak into the system???? but then why would my coolant temp gauge be affected by this???

Many thanks guys.
Jonathan

[rickgti]

is 90 not the normal running temp.... that's what it is on my golf:confused:

[v6dub]

90 is the normal running temp, what it sounds like is that you head gasket has gone,

[jonathan lovell]

wouldn't the performance of the engine be grreatly affected if the head gasket went, there's no smoke or mist coming from the engine and the oil and coolant levels do not seem to drop

[v6dub]

Well if your getting sluge under the oil filler cap, then there is water getting into the oil system, so the main way that water gets into the oil is from the coolant, so the head would be going, it would not affect performance if it was just starting to fail but it would start to get worse the longer you leave it, keep an eye on the water level and see if it is getting low, also what is your oil level at???
:beerchug:

[jonathan lovell]

Admittedly i think the oil level is falling quicker than it should do but not at a worrying rate, however like you said it could be early indication that the gasket is on the way out. how much are they to buy and is it a job that can be done at home or is it worth taking it to a garage? i have overhauled engines before but never tackled a VW one before!

[Lex Luthor]

The classic cause of mayonnaise at the oil filler cap is the engine not getting up to temperature, either because of short runs, or more likely in your case that the thermostat has failed open and the coolant never gets hot.

[jonathan lovell]

could this cause the oil pressure lamp to come on because it only does so when the car is first started on cold mornings? is a new thermostat fairly cheap and easily replaced?

[Lex Luthor]

could this cause the oil pressure lamp to come on because it only does so when the car is first started on cold mornings?
No. What oil are you using ?
How long does the light stay on for?
How long does the engine crank before it starts ?


is a new thermostat fairly cheap and easily replaced?

Yes

[jonathan lovell]

It is the right oil, can't remember what type off the top of my head, the engine starts straight away, no hessitation, sometimes the light clears straight away other times it stays on for a bit longer but when i switch off and switch on again it doesn't come up.

[Lex Luthor]

When it starts from cold, after being stood for at least 2 days, how quickly does the engine quieten down ?
I should take no more that 2 seconds for the tappets to pressurise and for the cam chain tensioner to take up the slack.
Have someone start it for you and have your head under the bonnet !
If it is longer then either the oil is too thick when cold or the oil pump may be on the way out or the pickup strainer might be partially blocked.

I have had success, on two older cars now, of using 5W40 fully synthetic to shorten this "quieting" period.

[jonathan lovell]

Cheers Lex, Ill try a thinner oil, it's passed it's MOT recently with no problems with regards to the exhaust emissions thats why i'm not convinced that it is as bad as the head gasket breaking down.