SINCERE Apologies for the SPAM answer you got from jamessizer... (a book peddler).
No serious mechanic is EVER going to tell you a "NORMAL" compression (nor should they).
As a well running engine runs through it's possible LIFE-CYCLE... It is highly probable the cylinder compression can decrease significantly (harmlessly... smooth as silk).
The ONLY reason to troubleshoot with a COMPRESSION GUAGE is to detect engine imbalance (like a dead cylinder)... looking for burnt / cracked piston, burnt valves etcetera...
If the compressions are similar... no MECHANICAL conclusions should be drawn from any specific pressures...
Hope this helps your understanding... especially of Jaguar Engines.
Factory manuals for my Jags were quite expensive... but also very informative... and there are some serious ENTHUSIASTs volunteering here if you care to elabortate on what issues you are having...
Good to have spares around... Those engines are amazingly robust...!! Do consider looking at the soft plugs (casting plugs)... for any signs of corrosion. They are TERRIBLY EASY to change when the engine is completely out & filly accessible (I'm just saying).Good to have spares around... Those engines are amazingly robust...!! Do consider looking at the soft plugs (casting plugs)... for any signs of corrosion. They are TERRIBLY EASY to change when the engine is completely out & filly accessible (I'm just saying).
Answers & Comments
SINCERE Apologies for the SPAM answer you got from jamessizer... (a book peddler).
No serious mechanic is EVER going to tell
you a "NORMAL" compression (nor should they).
As a well running engine runs through it's possible LIFE-CYCLE... It is highly probable the cylinder compression can decrease significantly (harmlessly... smooth as silk).
The ONLY reason to troubleshoot with a COMPRESSION GUAGE is to detect engine imbalance (like a dead cylinder)... looking for
burnt / cracked piston, burnt valves etcetera...
If the compressions are similar... no MECHANICAL conclusions should be drawn from any specific pressures...
Hope this helps your understanding... especially of Jaguar Engines.
Factory manuals for my Jags were quite expensive...
but also very informative... and there are some serious ENTHUSIASTs volunteering here if you care to elabortate on what issues you are having...
Good to have spares around...
Those engines are amazingly robust...!!
Do consider looking at the soft plugs (casting plugs)... for any signs of corrosion. They are TERRIBLY EASY to change when the engine is completely out & filly accessible (I'm just saying).