Compression

Big lumps of metals and spanners.

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banana
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Post by banana »

As no one replied to you I thought I would speculate ( as Im no expert) that cylinder no.1 is probably OK or maybe 5% down on compression but no.2 is therefore only running at 75 - 78% its normal. That would seem to be enough to suggest the rings on 2 are in very poor condition and thats why your oil is not lasting long. Thats my guess. Hope someone else gives you a better answer.
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TD
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Location: Leicester

Post by TD »

well if you engine has lasted that long you should get in in the Guinness Book, most of the non turbos croak at less than 100K, even the turbos at 100ish.

But I had a compression test on my old TD engine at 102970 miles and average compression pressure was 400Bar

But 6000 miles later it was a goner due to cracked head and oil burning.

My advice to you is not to worry until it either fails MOT through smoke or is using coolant big time, even then just top it up but stay in this country and join AA.
Hope this helps :)
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HarryMann
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Post by HarryMann »

The 390's low, could be valves but prob. rings. Castrol Magnatec has something in it that might clean the situation up, levelling pressures (read the guff). A bit akin to Magic Marvel oil in the US.. Change the oil, run it for 1000 miles or so and retake the pressures. Can't fix a broken ring of course, but it can free p stuck rings and reduce oil consumption a bit too. Else it's a rebuild

400 bar is nearly 6,000 psi :roll:

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