stripped timing belt

[3-Z-CARS]

Hi, weather is starting to warm up here in southeastern Washington so I need some help with my 1987 300zx. Last fall I went to start the car after work and nothing happened. I ended up taking it to a shop and they told me the timing belt needed to be replaced. Got the car back at the house and have the front end of engine off and got the timing belt removed, crankshaft pully etc., but my concern is whether the engine got ruined. I've put the crankshaft bolt back on a kinda of rotated the crankshaft very slowly, with the spark plugs out, and I didn't feel anything out of the ordinary. I just need some advice, can't afford to have a mechanic to do this and I've done a little engine work so I figured I'd dive into it and see what's up. Any help/suggestions would be greatly appreciated

[Ace2cool]

If it didn't start after shutting it off, it's possible the timing belt broke, but more than likely to me the shop was just trying to weasel some money out of you. More than likely they would have come and said "oh, ______ needs to be replaced as well...."

However, if there was an issue, the VG is a low tolerance interference engine, and it's possible there was piston/valve contact. A bent valve can feel normal while rotating. Was there a physical problem with the belt? The only real way to tell is to compression test it, or start it up and see if it runs correctly.

Also, this section is for the Z32 ('90-'99) 300ZX. I'll move this to Classic Z.

[3-Z-CARS]

The belt wasn't broken but there were quite a few teeth that were gone and shredded debris at the bottom. Thanks for the reply. I'm really lame at navigating this site. Don't know what the heck I'm doing, posting a ? etc. Not a clue.

[evildky]

short of putting it back together and seeing if it fires, you can do aleakdown test on each cylinder, if the valves are bent it'll be obvious.

[3-Z-CARS]

Leak down test? Not sure what or how that is done. Does it have to do with some kind of compression test? So do all the spark lugs have to be in and then one individully taken out, at a time, and some sort of compression gauge hooked up? Putting it all back together sounds like a pain, but do-able. Not sure about timing and all that. Thanks for the input! :-)

[evildky]

leakdown test you hook to one cylinder at a time through the spark plug hole and use shop air to pressurise the cylinder then measure the loss.

[3-Z-CARS]

Hey, thanks for the info! Sorry I haven't replyed sooner. I think I'm just going to get the parts I still need, i.e. water pump, front main seal and thermostat and start putting it back together. I'm not sure how to get the timing marks set up, so if you have any suggestions I'd really appreciate it.

[evildky]

you set the crank at tdc, there is a notch in the oil pump housing that lines up with a dot on the crank gear, then set the cams so the dots on each line up wiht the dots on the backing plates, it's all laid out in the fsm, or haynes or chiltons