Wanted to see if anyone had any input I have a 2005 S40 2.4 that won't start but cranks I believe it's getting fuel cause gas is shooting out the fuel rail and it smells like gas really bad when I try to crank it over buty question is can a worn timing belt cause a crank but no start and also should you be able to move the timing belt with your hands because it's that loose it's looking like it wants to move to outer edge when I crank it over and it must of been doing it for bit cause some of the plastic timing cover is melted a little so any help would be appreciated thanks.

 

If the timing belt has jumped more than a couple teeth, chances are VERY high that you are in for a world of pain. The engine is an "interference engine", meaning that the valves normally extend down farther than the pistons travel up. These are kept apart by the timing belt coordinating their movements, but if it's slipped much at all, they've probably gotten into a fistfight, and at the very least it'll require a new or rebuilt cylinder head to fix (big bucks).

If the engine was running fine and then suddenly died, AND you're very lucky, it only slipped enough to keep the engine from starting, and not enough to destroy the valves.

Thing is, if you CAN move the timing belt by hand, something's drastically wrong (probably the timing belt tensioner). Pretty much zero chance that the slippage wasn't "severe" in that case.

 

​Ok thank you very much for your input the car did die all of sudden and we had it towed home but if I crank it over would I here a bunch of bad noises if the valves are junk? Thanks again

 

Two possibilities... 1) The valves got munched enough that they no longer contact the pistons, or 2) The timing isn't off enough (yet - be careful!) that they never touched.

I'd suggest taking a look inside the pistons with a borescope (you can get a reasonably nice one that uses a smartphone for chump change on eBay or Amazon). You should be able to see evidence of violence on the piston faces if the worst happened.

If not, you need to do a timing belt, etc. (water pump, tensioner, etc.). It's not all that trivial a job on a Volvo I5, but is DIY-able if you don't mind buying a couple very specific tools (lots of threads here on that subject).

 

if you don't have an inspection cam, a simple compression test will do. very low to no compression = bent valves, mid to low compression can be cam timing related. a 2.4i should have somethign like 170-180 PSI compression - a turbo will have 150-160 and you'd probably need 100-120 to get the car to start (last one is just my guesstimate)

 

mt6127, does a compression test work with slipped timing? I've always assumed that it won't, but I suppose it might be dependent on the number of teeth the belt slipped...

 

really depends on how far its slipped but my thinking is if the belt has slipped its more likely to have damaged valves than not. I recall some other posters noting that their compression fell off with the timing being a bump or two off...