My friends Peugeot XU 1.9 petrol engine is oil smoking from start-up at tickover or fast tickover speeds, hot or cold.
1) What should the Compressions be when doing a compression test.
2) Can the Valve stem seals be changed in situ, without removing the Cylinder head.
I know the cam will have to be removed, but can it be done?
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The compression depends on the exact engine code this XU9 lump is.
Around 120 psi + is what you should be looking for roughly, All 4 cylinders should be around the same result.
The XU9 engine has liners & the seals can fail.
Yes the valve stem oil seals can be changed in situ, Nice long bit of nylon string fed through the spark plug hole, turn the engine over so the pistion holds the valves shut tight.
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while not being aufair with stripping a wet lioner pewgot engine down i would be miffed if my tester showed 120 a pot i would want a minimum of 150 and ideally 175............
i do stand to be corrected though...........
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Thanks for your replies
The XU9 is a GTI motor and the compressions he has are between 200/213 psi when the engine is hot. Which I don't think is too bad.
I understand the point of putting something through the plug hole to hold the valves up, But how do you or what do you use to compress the Valve springs to remove the cotters.???
thanks
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Ingenuity, in spades. Mike
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I think you can buy special tools, particularly for fords, but on similar engines I have used a pair of safety specs (in case collets go flying!), tap top of spring lightly using small socket (so freeing , but not releasing, collets from holder) then 1 guy holds spring down with suitable ring spanner whilst mate uses magnet to pick out collets.
Lots of fun if spanner slips, as collets are difficult to locate in garage jumble
Was much younger, and enthusiastic, in those days
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I've used the "rope trick" successfully on a different car.
1) lock the crankshaft well - you don't want it suddenly turning backwards. I used a large ring spanner on the nut, and roped the other end tight.
2) plug every single hole and oilway on the top of the engine. If a valve collets falls down inside the engine you have created a new job extricating it.
3) a makeshift compressor worked well for me. It was just a flat bar like a tyre lever, with a large hole at one end losely held under a camshaft bearing bolt with a large washer, and then a concocted bit of cut-away tubing to press the valve but still give acces for fine nosed pliars to extract the collets.
With the valve freed you can cautiously release the crankshaft a fraction, to drop the valve say 1/4", and then check for wear in the guide.
An alternative is an adaptor and compressed air, but you are at the mercy of sudden leaks and decompression.
I have recently heard of someone who successfully recovered a dropped valve by removing the inlet manifold and coaxing the valve back up into its guide with a bit of wire through the inlet port.
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I totaly agree with oldman peugeot petrols run at 150 to 175 psi your engine is suffering from valve stem oil seals going hard this is a commun fault of thios engine,however saying that when I worked for peugeot the way we did it was take head off then check for bore wear or heavy blue tingeing of bore liners. or you can do what we call a cylinder leakage test as this will show up any ring problems[megrandad] if heavy oil contamination of bores this is due to ring failure[megrandad]
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