04-11-2015, 10:52 AM
(This post was last modified: 04-11-2015, 10:56 AM by pug306driver.)
Nice looking combustion chamber, apart from the damage that is....
Car sat for 2 years ? maybe a clue there.......
You live close to the coast, or in a wet/humid area ?
Valves can and do ( I have seen it myself on older vehicles, engines etc ) stick open, with catastrophic results, as we have seen.
Some valves will be open when the engine is a rest, so any dampness will get in the cylinder eventually, not to mention any gum etc on the valve stems.
The engine turned over by hand ( rather than just jump starting and whizzing the engine over on the electric starter ) , which is always a good practice on engines that have been standing for a while, but inclined valves are a bit different, as they are "inclined" to get bent ( if stuck open ) by the up coming piston.
Turning the engine over slowly by hand, its as well to watch all the valves open and close, feel for any "clunk" or tight spot ( valve touching piston ) and watch for "enlarging valve clearance gaps", suggesting a stuck open valve, with the plugs out and some oil down the bores. Some oil or lub on the rockers/buckets etc and on the valve springs and upper stems is also a good precaution. Over the top, no, not really, just see the pictures.
Not too difficult on a 4 cylinder but much more complex on a v12 believe you me.
In the old days when most valves ( not all by any means ) where inline with the pistons, a stuck open valve would be "snapped shut" by the up coming piston, a gentle nudge ( when turned over by hand ) to free the stuck valve off. You would hear the "whack/crack" of the valve slamming shut.
A tv comedy show with a "master mechanic" ( my god he don't half break a lot of stuff ! ) says that the engine should be turned over by hand ONE REVOLUTION, yeh that's why he's a master, right ?
Watch the blue FIAT/SEAT episode, the car not sounding too healthy as its trying to start, sounds like a low compression, starts sort of, backfiring thru the carb until it suddenly clears, stuck valve maybe ??
So, be warned, if the car has been sat for some time, think stuck valves, take your time and be very careful.
Car sat for 2 years ? maybe a clue there.......
You live close to the coast, or in a wet/humid area ?
Valves can and do ( I have seen it myself on older vehicles, engines etc ) stick open, with catastrophic results, as we have seen.
Some valves will be open when the engine is a rest, so any dampness will get in the cylinder eventually, not to mention any gum etc on the valve stems.
The engine turned over by hand ( rather than just jump starting and whizzing the engine over on the electric starter ) , which is always a good practice on engines that have been standing for a while, but inclined valves are a bit different, as they are "inclined" to get bent ( if stuck open ) by the up coming piston.
Turning the engine over slowly by hand, its as well to watch all the valves open and close, feel for any "clunk" or tight spot ( valve touching piston ) and watch for "enlarging valve clearance gaps", suggesting a stuck open valve, with the plugs out and some oil down the bores. Some oil or lub on the rockers/buckets etc and on the valve springs and upper stems is also a good precaution. Over the top, no, not really, just see the pictures.
Not too difficult on a 4 cylinder but much more complex on a v12 believe you me.
In the old days when most valves ( not all by any means ) where inline with the pistons, a stuck open valve would be "snapped shut" by the up coming piston, a gentle nudge ( when turned over by hand ) to free the stuck valve off. You would hear the "whack/crack" of the valve slamming shut.
A tv comedy show with a "master mechanic" ( my god he don't half break a lot of stuff ! ) says that the engine should be turned over by hand ONE REVOLUTION, yeh that's why he's a master, right ?
Watch the blue FIAT/SEAT episode, the car not sounding too healthy as its trying to start, sounds like a low compression, starts sort of, backfiring thru the carb until it suddenly clears, stuck valve maybe ??
So, be warned, if the car has been sat for some time, think stuck valves, take your time and be very careful.