2003 mini cooper s won't start (timing issue?)
 

i'm thinking about buying a used mini cooper s that won't start
the seller says he's sure it's a timing issue (because it has fuel and spark)

I've done some searching and haven't come with some some details, hoping you guys could please help me out

1. what's the best way to diagnose if this is correct?

2. how hard of a fix is this? it looks like the timing tensioner isn't too bad to do but if it's jumped the chain could it have caused valve damage? I'm guessing these are interference engines

Why does he think it is the timing?? history of a problem? Could be crank or cam sensor!!
Yes they are interference motors --valve damage is likely if the chain just jumped..best be careful. Best to price it to require head work.
You would need to the the front cover (oil pump) off to reset the timing and change the chain etc--fairly big job.

excellent question. i think he's just trying to get rid of the car.
he told me it's an easy $400 fix but he doesn't know how to do it, and he's sure it's timing since he has spark and fuel.
sounds fishy to me.

i've done subaru timing belts, but it sounds like it's as big or bigger than that

It's not that big a job, but more difficult with the engine in the car (takes about 4hrs if you've done it before--so figure a whole day). You will need a new chain and tensioner (optional, but while you have it apart)--tools--crank puller, cam position tool and serpentine belt tool . You will also need a new set of oil pump seals, crank bolt and cam bolt. The job is fairly straight forward, but you need to remove a lot of stuff to get at it all--fender liner, crank pulley,belt tensioner, intercooler, move the engine up and down to get at some of the bolts etc.etc. SO kind of a pain in the ass.

If you can get it cheap enough it might be worth it--I would check/replace/borrow a cam and or crank sensor before looking at the timing--unless he has a real history of the chain being the issue.

Price it like it needs a new/rebuilt head--because if it is the chain then some valves are likely bent. How many K on the car?

just over 100k on the car, the guy wants $4k for it

Not worth that kind of money. Could be all kinds of things and if he thought it was a $400 fix strike a contract with him that says you will pay him $4400 for a running car. Think of this as a hedging moment.

If it has done damage you will hear it as it cranks over - THAT IS WHEN YOU WALK. The rest is up to you.

You won't hear anything when cranking it over if valves are already bent (they have made their own clearance) the car will just fail to run or run very poorly when started.

i agree. he said it'll turn over but won't fire up
when i asked how he knows it's the timing the response was "i just know"

Timing issue on a gen1 isn't common & he just knows? I hope he can tell you more about the car's history than that. If not bent valves, it could be either ignition or fuel supply & pressure. The latter can easily be checked by fuel pressure gauge hooked on the schrader valve under the intercooler. It should read above 50psi upon priming the pump w/o cranking.