Project escort, removed pistons and found some marks like valves had given them a kiss, 1 i could understand but all 4???
start with the head,
Bit dirty but no damage


Pistons after a clean-up with some neat petrol





All 4 marked in same place, no damage to head..... Has it had a snap and been revalved??????!!!!!!! Definatly not ment to be like that unleas they mchined them with a hammer and chisel because they are definatly knocked!!
Any ideas?? The valves are undamaged and the marks on pistons were all mucked up so guessing not recent, im pretty stumped as could be a number of wrong doings, head skim, gasket, wrong lift clearence, wrong pistons, wrong valves at some time.... Any ideas??

 

looks like timing has been out at some point maybe? and its been fixed on the cheap...

 

as above probs snapped a belt before and bent valves before due too crown down damage like that

 

they have defo been in contact with the valves before and not changed

 

With it only being one side would that indicate one cam was out and thus only one set of marks

 

more than likely the timing was slightly out causing the valves to come in contact with the piston,

 

my money is on a previously snapped belt. If its a n/a motor then i'd make sure the valves are sealing ok and then just clean the burrs off the pistons with some emery tape and oil

 

As said timing or belt snaped could be the head was swoped out with a replacement ?

 

Why if it's n/a any engine needs correctly seated valve not just a atmo one!

 

Jim, I think the n/a comment was more to do with the pistons rather than the valves. As you say, all engines need the valves to seat/ seal correctly.

 

Dosnt come across anything to do with pistons to me?

 

its over revving that causes this kind of damage mate if it were a timing belt failure the exhaust valves would have made contact too !!!

 

Heads going in shop tomorow for pressure testing clean up etc, may get a bit of head work done while its in...

 

my pistons were exactly same when i missed a gear! as said over rev!

 

could have been worded better but Rob got what i mean't, Go find some tech thread to nit pick in