m3vs911

Hi mates, hope everyone is having a good time with your 964s. I've recently realised the oil leak of my 1990 c2 is (seems!...) getting worse that I start to get worried. Let me try to summarise the background...

Originally there are 3 oil leak locations that i reckoned, they are
- the engine itself
- oil lines between the oil tank next to the right rear rear wheel
- somewhere around the front oil cooler

- oil cooler fan has shot
- oil level sender has shot

so i've brought my car to my mechanic and get these done...

- entire new oil lines from the engine all the way to the oil cooler
- new oil cooler fan , and clean the oil cooler , reseal the part that connects between the oil tank and the oil lines to the cooler
- new oil level sender
- shell helix oil 10w60

Recently when I have my car back, I am happy with the 2 oil leaks at the oil cooler and the oil tank location are gone. oil temperature is low enough that won't show me problematic readings from the temperature gauge (ambient temp here is about 20-30 degree C day time) and I can feel strong wind from oil cooler location.

Problems:
Oil leak from the engine that mark on the floor is getting bigger than before,
it is obvious to me every time when i get back to the car. therefore I start to look at the oil consumption and top up frequency.

from Adrian's book, the working temperature for the engine should be at 9 o'clock position , which i can only get it reaches at 8 even if I let it idle for 15mins . (I used to be able to hit 10 o'clock position before getting the cooler fan fixed in some hot days)

so after leaving the car on flat road and idle, the level gauge will not register at all and always point around red zone. from the dip stick i can see 1/4 oil there. so I topped up 500ml and i start to see the level gauge move and gets to somewhere about 1/3 - 1/2 position. I am happy with it and switch off the engine.

few days later (been driving for about 500miles) , the oil gauge shows low again and I have to do the same thing again, and again..

My questions ...

is that my oil temperature too low that causes the oil level reading at low?
or am I just over-worried about my oil level as 964 do leaks most of the time? When I leave the car at idle , the pressure gauge doesn't stay stable, it can sometimes bounce from 2-4 (but not always) but will not get to 1 unless the oil is low and stay idle at up slope. Does it mean the pressure sender is shot too ? I've heard that the pressure sender could cause oil leaks too?

Been owning the 964 for 3 years since 110k miles (124k miles now), these problems really start to get on my nerves

m3vs911

used water jet to wash out the oil grime , drove it to a dry area, and spent 3 mins to observe. and most of the leak is from this jubilee clip. has anyone got any clue on this ?

placed this bottle to collect for tomorrow morning...
https://fbcdn-sphotos-d-a.akamaihd.n...55418222_o.jpg

jevvy964

That jubilee clip is only holding the heat protective wrap on the oil line - there is no join in that area so the leak is higher up and leaking down.

The oil is still expanding @ 8 o clock so you wont be getting a proper "hot" level. Idling a 911 engine for 15 mins aint going to do it any favours whatsoever - go find a quiet road and rip the **** out of it to get it to proper temps then check the levels.

Is that the last outstanding leak? Have you looked at the backside of the rear wheel arch where that pipe terminates? I'm guessing that's yr source.

m3vs911

I am not sure about this, haven't got a chance to check the location where the oil pipe terminates at the rear wheel arch yet. I will try to sort it out tomorrow, at the moment I think i can just keep an eye on it ...

and the oil does leak from some other part of the engine, but they aren't really noticeable in a short period of time, apart from the location in the pic!
heard that some of them could be fixed without dropping the engine... the gasket of the valves cover ?

does it really make a difference in oil level before the temp gets at 9 o'clock ?

cheers ,
arthur

Vandit

Yes.

m3vs911

i tried to get a spirited drive tonight , did 80 mph for 5 mins on the motorway but the temperature was even lower than 8

i thought thats normal as air should be blow to cool down the oil more...?

or there is another proper way ?

ras62

Cover the engine lid air intake with a blanket while running the engine. The engine will soon warm up. When the front wing gets hot from the oil pipes underneath is the time to check the level.

jevvy964

Yr doing it wrong, you need to find somewhere that you can go at least 1st to 3rd at full throttle through each of the gears, turn round and do it again until you get it hot. Blasting along the motorway @ 80 with low ambient temps is perfect oil cooling territory for a 911 - you got to work it a bit

AVI_8

Get your car up to normal operating temperature, then let it idle for 5 mins and check your levels, you don't have to run it for a few mins at full throttle through the gears in order to check the oil levels, the oil temp will increase when idling and stationary once it's warmed up

m3vs911

this sounds new to me!
did you mean to cover the vents on the spoiler with the engine running ?

ras62

Exactly. Go for a drive to warm the engine then park up and cover the black air vent. The engine will warm up much faster.

jevvy964

These engines are designed to deal with heat generated through use not from choking them. Why leave it idling for 15 mins when 2-3 strong runs will get the job done much quicker and get the engine hot in all the right places instead of all the wrong places. YMMV

ras62

Jevvy, not sure what you mean by warming all the wrong places but getting the engine hot is not always easy if the ambient temp is low or traffic does not permit big revs on the gas. Covering the air intake does no harm whatsoever and is a quick and easy way of bringing a motor up to temp.

Michael D'Silva

Interesting thread.. hope you find the source of your leak...
Is the right hand heat exchanger burning off some oil as well?
Or does it just seem to be coming from that rear line?

J richard

FWIW, don't pay too much attention to the oil level guage. They are notoriously inaccurate and depend on so many variables; level temp time of day and orbit of the moon.... The dipstick is the way to do it. If you can't get the car warm in short order, even on a cold day it could mean your stat is stuck open/not closing. Check the temp of the oil lines to the front cooler and see if they remain cool until the motor is warm or if they start to warm immediately.

If you are at the age where the lines were toast you can pretty much assume they all are. Also I would check your oil return tube seals as they age very similarly...