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OK, valves hit pistons, all good.
Bent 2 - bit weird..
Even weirder that its 1 in no 2 and one in no 4!
why not both inlets in each chamber?
The both open together and the piston is flat...
anyone had this?
possibly to do with valve spring weakness.. had you had any valve change pout before, stem lenght maybe be different betwwen valve's and the hydraulic follower compensated, or are they mechanical ? im interested
1991 S2 3B Coupe, KW v1, solid sub frames, poly bushed, chipped, about 260 ish
Because when the weaker valve bends it relieves pressure on the other valve, and the firing order is 1,2,4,5,3... So the next cylinder to suffer from the 'error' is the next in the firing order...
85 WR Urquattro, 85 20vT International liveried RallyRep
93 MTMS2 Avant
Because when the weaker valve bends it relieves pressure on the other valve, and the firing order is 1,2,4,5,3... So the next cylinder to suffer from the 'error' is the next in the firing order...
ok. i want to understand what you posted. how did only 1 valve hit the piston if both open same time and at same rate, closing rate could be different, i just cant figure out what you mean, even if 2 valves hit and 1 bent the force on the other would increase would it not ? im in no way denying what your saying, just want to learn
1991 S2 3B Coupe, KW v1, solid sub frames, poly bushed, chipped, about 260 ish
possibly to do with valve spring weakness.. had you had any valve change pout before, stem lenght maybe be different betwwen valve's and the hydraulic follower compensated, or are they mechanical ? im interested
One Hydraulic lifter empties easier than the other or has
some air in it, an empty one gives ~3mm more valve clearance.
OK Ian, but as the piston is bending one, how does it not bend the other? have you seen this before? im thinking to change the others too.
it all depends on the forces at the point of failure, if its pre-ignition enduced failure then as the piston is rising in the bore the early entry or early ignition of the fuel will force the piston down and the valves closed prematurely, bending the valve... If its through cambelt failure or similar, everythibg just gets mullered. My guess is the timing/boost/pre-ignition has occurred and uncontrolled, bending the weaker intake valve to relieve the pressure... I'd change all of the intake valves, and check the stronger exhausts for weakness..
85 WR Urquattro, 85 20vT International liveried RallyRep
93 MTMS2 Avant
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