Locating an oil leak
Discussion
I have a MK1 I've gradually been fettling and having fettled.
In the last few years it's had a swap from auto to manual, an interior swap out, and some welding work. I.e. it's been interfered with a bit.
It's developed a small oil leak, which I thought I'd fixed by installing a gravel drive. Last night I parked on the road and it's reminded me that the leak is still there.
It's not immediately apparent where the leak is coming from. Are there and 'usual suspects' when it comes to mk1s?
In the last few years it's had a swap from auto to manual, an interior swap out, and some welding work. I.e. it's been interfered with a bit.
It's developed a small oil leak, which I thought I'd fixed by installing a gravel drive. Last night I parked on the road and it's reminded me that the leak is still there.
It's not immediately apparent where the leak is coming from. Are there and 'usual suspects' when it comes to mk1s?
The gravel driveway is a pretty novel solution, though it didn't help me when I tried parking my car on a steep gravel driveway when it had an oil leak...
Things prone to leaking in no particular order - and telltale signs (not definitive, just my experience). Try these and then wash your engine bay/degrease your engine bay - they're cheap!
CAS O-ring - Oil tends to drip down the back of the engine. On a 1.8 you can see oil stains on the heater hoses occasionally. Not sure on a 1.6 I guess EGR piping and wiring loom? Can eventually drip around the gearbox and make the uninitiated think the rear main seal has gone!
Valve cover gasket - look for oil dripping down the head to the bottom of the block.
Camshaft end caps - there should be some blobs of silicone RTV on the corners on the two front caps and the cap that holds the cam angle sensor. Worth re-doing with a new valve cover gasket
Oil filter and oil cooler mount - is the filter on tight, undamaged and making a good seal with the oil cooler mount/filter mount? (ask me how I know..)
Things less prone to leaking in no particular order - and telltale signs (in order of least PITA to most PITA, assuming you are quite mechanically inclined)
Front main seal - if there's oil around the oil pump/behind the harmonic balancer
Rear Main seal - did you swap it on your gearbox swap? Worth noting I changed one on one of my engines because I mistakenly thought a hidden valve cover gasket leak was actually the rear main seal as the leak appeared to be coming from where the bellhousing attaches to the motor
Sump gasket - typically siliconed on, PITA to fix if it is that. Look for oil below the sump but not above
HTH
Things prone to leaking in no particular order - and telltale signs (not definitive, just my experience). Try these and then wash your engine bay/degrease your engine bay - they're cheap!
CAS O-ring - Oil tends to drip down the back of the engine. On a 1.8 you can see oil stains on the heater hoses occasionally. Not sure on a 1.6 I guess EGR piping and wiring loom? Can eventually drip around the gearbox and make the uninitiated think the rear main seal has gone!
Valve cover gasket - look for oil dripping down the head to the bottom of the block.
Camshaft end caps - there should be some blobs of silicone RTV on the corners on the two front caps and the cap that holds the cam angle sensor. Worth re-doing with a new valve cover gasket
Oil filter and oil cooler mount - is the filter on tight, undamaged and making a good seal with the oil cooler mount/filter mount? (ask me how I know..)
Things less prone to leaking in no particular order - and telltale signs (in order of least PITA to most PITA, assuming you are quite mechanically inclined)
Front main seal - if there's oil around the oil pump/behind the harmonic balancer
Rear Main seal - did you swap it on your gearbox swap? Worth noting I changed one on one of my engines because I mistakenly thought a hidden valve cover gasket leak was actually the rear main seal as the leak appeared to be coming from where the bellhousing attaches to the motor
Sump gasket - typically siliconed on, PITA to fix if it is that. Look for oil below the sump but not above
HTH
Edited by mrciarano on Thursday 28th November 20:30
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