Pressure under oil filler cap

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JimH240
1.8 8v
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Joined: Sat Jun 30, 2007 5:08 pm
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Pressure under oil filler cap

Post by JimH240 »

Hi
Got a 2000 HDI 90 Rapier. 168K miles. Had it 10 years. Great car. Completed an oil and filter change and checked for leaks etc next day after a half hour run. Undid the oil filler cap and noticed a bit of blue smoke coming out under quite a bit of pressure. Never used to have any pressure when i've undone the cap on previous occasions. Car uses almost no oil and performance however seems same as ever.
Pulled off the big central breather pipe but only at the end at top where it meets the crankcase cover just to see what would happen. Nothing changed with pressure staying the same. Is it worthwhile to take the breather pipe off completely? Is there a filter in the breather that maybe needs cleaning out? Or is it all just wear and tear and keep fingers crossed?
Any hints infor be grateful as i really like the car.

Jim
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Welly
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Re: Pressure under oil filler cap

Post by Welly »

Sounds like a breather issue, could be worth removing it and looking at the bottom part, I know you've had the car a long time and this will sound daft but you haven't over-filled the oil at all?

Has the car been used for constantly short journeys? this can lead to a build up of residue in the breathers.
Cars in my care:
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2013 Renner Twingo - donkey work
JimH240
1.8 8v
Posts: 25
Joined: Sat Jun 30, 2007 5:08 pm
Location: Bromley Kent

Re: Pressure under oil filler cap

Post by JimH240 »

Put in the usual 4 1/2 litres oil and do varied journeys. Car used daily to work 12 miles each way. If take the breather off, do I need to drain oil from sump first?
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Welly
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Re: Pressure under oil filler cap

Post by Welly »

JimH240 wrote:Put in the usual 4 1/2 litres oil and do varied journeys. Car used daily to work 12 miles each way. If take the breather off, do I need to drain oil from sump first?
You shouldn't need to as the breather should always be above the oil level of the sump. It'd be worth doing a bit of homework before you try the job, maybe have a new hose assembly and fixings to hand; these things have a habit of breaking when removed for the first time.

To be fair I wouldn't worry too much about this if the car's alright otherwise, maybe ask if others with a 90bhp can check theirs does the same thing?
Cars in my care:
2021 Kia Spottage 1.6 Pez Turbo Dual Clutch Gearbox Trickery
2013 Renner Twingo - donkey work
runner1
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Re: Pressure under oil filler cap

Post by runner1 »

My car does the same thing but I know the head is venting in to the coolant system. Checked the top breather in to the air intake which was clear. I assume there are other pipes I need to check?
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