The cambelt tensioner on my g/friends car has spat out its bearings causing the unevitable piston valve contact! Its gunna need 4 new exhaust valves, the inlets look ok Im not sure ifthe guides are bent tho, whats the best way to check? Heres a pic


Also theres some contact marks on the pistons, iwas thinking of just sanding them a bit coz the crank turns ok and theres no marks on the bores, what do you think?



Any advice would be greatly appreciated before we shell out on new bits!
Thanks [/img]

 

Anyone?

 

I wouldn't have thought you'd bend guides, take the valve spring off, and see if they slide nice, I'd of thought so, you got to be VERY unlucky to bend guides

 

I usually just slide down a new valve and give it a rock about to check if its okay. And If it were mine I wouldnt worry about the pistons either. New valves will need lapping in so you should be able to tell from the fine grey line it leaves if they are seating okay

 

Cheers Will get hold of some valves on tues when the shops are open.
How do you "lap" the valves in?

 

grinding paste, and a stick, buy both at a motor factor, first course, then fine in a trying to start fire motion, until there is a grey ring around the valve seat! it takes time to get it right!

 

Valve grinding paste and a lapping stick

Put some on the seat of the new valve and a couple of drops of oil and lap away. Turn the valve a quarter of a turn every so often until the new valve is seating correctly all the way round

 

ar, i get it, nice one

 

Some how sounds better than the way I put it!

 

We have things called lighters up here to start a fire

Same thing tho .... "lap away" and Dont get any paste onto the stem of the valve whilst your doing it either - but a drop of oil helps

 

Ha ha funny guy





But soooo right

 

other way round, surely? Inlets bent, not exhausts..

if the seats in the head look clean, go straight for the fine lapping paste and see how it goes, may save a chunk of time and effort. The poo paste that factors usually sell is lumpy and fookin lumpy anyway, "fine" is usually a matter of opinion.. lol