I've just bought an 1998 XC70 with possible engine damage but before I open up the engine I wanted to know what you guys think.
Basically the ex owner changed the headgasket and when he put back the timing belt he forgot to put the pin in the belt tensioner and as soon as he tried to crank the engine he lost the timing and compression. So now the engine turns freely with no noises and no compression.
My mechanic says he'll adjust the timing and try to start it before he opens the head.
What do you guys think?

 

these ARE interfearance engines, you have valve damage if you have no compression, time to tear it apart.

 

If he did something wrong yes the valves are bent.
But something about the explination above is fishy.
You said he forgot to put the pin in the tensioner?
You remove the pin after installing the belt. The tensioner gets compressed and the pin holds it compressed. After installing the belt you remove the pin.

 

Something definitely does not sound right about that explanation. Tech is right, the pin is pulled AFTER the belt is on. Unless he said he forgot to pull the pin out. That would keep the tensioner compressed and with no tension on the belt, it would definitely slip.

One should ALWAYS turn the engine over by hand several times after changing the belt and before starting it. A lot of trouble can be avioded that way.

Good luck and let us know how it goes and if you need any help.

Glenn