Have done repairs took shortcut ...

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Referring to similar thread...
"Have done repairs, car won't start"
My repairs were to replace a damaged timing chain guide.
Doing the job properly requires the engine to come out, the heads to come off, the lower sump cover and the upper sump covers to come off.
Remove the timing chain covers, fix the chain guide,

Reassemble.

I didn't remove engine, I did not remove cylinder heads, I did not remove upper sump cover :p .

I did manage to get the timing chain covers off, fix chain guide and re-assemble timing chain covers around the cylinder head gaskets and the upper sump cover gaskets ................:D

BUT :( after testing everything from sensors to sparking to fuel supply I finally tested compression..................:(

I have no compression on two cylinders, 8 bar on two cylinders, 7, 9, 9.5 and 10 bar on the rest when I should have at least 11bar on all of them ................

So are there any ways in which I can correct this without removing my engine ? It's a speculative question as I'm pretty sure there's only one answer and it's not a nice answer................. so much for taking the short cut ?

[revert]

Possible to leak past rings only ?
Is it possible that I've lost compression due to damaged rings ?

How bad is this going to get !!!!

[Bill R.]

m60 motor should be 12 bars minimumhttp://www.bimmernut.com/%7Ebillr/images2/compression%20for%20v8.jpg

I would almost guarantee that either you still have the cam timing off or you have bent some valves.. The other remote possibility is that its a nikasil motor and the bore is gone on some of them...




[quote=revert]Referring to similar thread...
"Have done repairs, car won't start"
My repairs were to replace a damaged timing chain guide.
Doing the job properly requires the engine to come out, the heads to come off, the lower sump cover and the upper sump covers to come off.
Remove the timing chain covers, fix the chain guide,

[revert]

Yeah thanks Bill,

I phoned around a little and somebody said to me that "no compression" means more than a little leak - like the valves are all opening at the wrong times. So I agree and don't have a problem with the additional fire. Opened up again and now I'm busying rotating the crankshaft and checking the position of each valve.

Firing order is 1 5 4 8 6 3 7 2 and back to 1. Having a little difficulty sussing out when valves are opening and closing since they're all doing their thing together. I had drawn up a diagram through the 360 cycle (x2) of the crankshaft and now I cannot find the elusive document. Anyway, trundling along some more.

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I have the "tappet covers" off, the crankshaft set to TDC and I notice that the camshafts on the block with cylinders 5 to 8 are still in their correct position. But the cams for block with cylinders 1 to 4 are out by a few degrees.

When I did the adjustments I also used the special tool that you wind into the chain tensioner slot up to 1.2Nm - I notice that my chain tensioner does not push the chain as much as the special tool. Either
a) Is this typical ?
b) The chain tensioner was replaced by the BMW dealership before I took the car away from them (lots of money and no progress .... ) so I'm assuming that they did actually replace it and that this little guy is supposed to not tnsion as much as the special tool. Maybe the tensioner needs replacing ?
c) The chain is stretched and the special tool should not have been able to tighten the chain more than the replaced tensioner ?

Or maybe I have a few too many bent valves :(

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After repeating timng checks and this time being absolutely sure of the alignment of the cams and crank to TDC I came up with worse results:
Compression results before and after re-adjusting
Cyl 1 = 8.0 / 7.5
Cyl 2 = 0.0 / 0.0
Cyl 3 = 10.0 / 7.0
Cyl 4 = 9.0 / 6.0
Cyl 5 = 7.0 / 3.5
Cyl 6 = 9.5 / 7.5
Cyl 7 = 0.0 / 0.0
Cyl 8 = 8.0 / 6.0

What's the opinion: Stretched timing chain or bent valves ?

How can I test to determine which it is ?

[Bill R.]

pull the valve cover on the cyinders that have no compression and rotate the engine so that cam is on the heel for that cylinder first for the intake, look and see if there is a space between the camshaft lobe and the hydraulic valve adjuster, if there is a gap then the valve is bent




After repeating timng checks and this time being absolutely sure of the alignment of the cams and crank to TDC I came up with worse results:
Compression results before and after re-adjusting
Cyl 1 = 8.0 / 7.5
Cyl 2 = 0.0 / 0.0
Cyl 3 = 10.0 / 7.0
Cyl 4 = 9.0 / 6.0
Cyl 5 = 7.0 / 3.5
Cyl 6 = 9.5 / 7.5
Cyl 7 = 0.0 / 0.0
Cyl 8 = 8.0 / 6.0

What's the opinion: Stretched timing chain or bent valves ?

How can I test to determine which it is ?