I have a 2000 Jeep Cherokee Sport 4.0

Anyway I replaced the water pump and the vehicle cranks but does not start. Because the engine overheated due to pump failure a friend suggested either the timing chain is off alignment or broke, or possible crank sensor CPS.

any ideas???

 

A more accurate title would probably be "overheated...now won't start". Unless it was running fine before the water pump job, the water pump probably doesn't have much to do with it.

Your next step is a compression test. You can usually rent the tool from local auto parts stores.

 

Do you have any engine codes?

​​​​​​​I'm not sure how the timing chain would be thrown off by overheating...breaking is rare.. usually they stretch out. How bad did it overheat?

 

Fuel, air and spark. One is missing.

 

No error code came up when I turned key on and off 3 times to retrieve it.

 

I think a compression test would help to verify. Just curious... have you checked your oil? not really for the level...but to see if you've got coolant mixed in it. If it overheated bad enough, could have cracked the head and or block.
side note... not priority at this point.. but when you replaced the water pump, did you also replace the t-stat as well?
I say work on the higher priority things first to track down where the damage/issue of not starting is.

 

as far as I coukd tell oil looked fine. I didn't detect coolant being mixed in with oil

 

If it ran well before the overheating, it should run now if the overheating didn't do any damage. If there was extensive damage caused by overheating, you need to have it looked at.

First, Did you check for spark? If you did, is there spark? If there is, is it blue and does it "SNAP" when it sparks, or orange-red and seem weak?
Second, if spark is present, will the Jeep run on a short spray of starting fluid?
Please report back after these things have been tested.

 

That's good... When you have a severe overheating issue all kinds of nasty things like that can happen... so good to check.

 

Not a bad idea... just as with any "fire".. you need 3 things or you have no fire....air(o2), fuel, and an ignition source.
Now... being of the older school growing up on carb style cars, the old starter fluid trick especially in a new or engine that has been sitting a while is an easy straight forward thing to do.
I do NOT claim to be an expert on this...and if others have used that step on a fuel injected vehicle and had success then great, but there's a bigger risk of causing damage using that trick on a motor with fuel injection. But it can be done... just don't use the same amount you would use in a carburetor, or I think you'll be sorry.
I would check for the spark and other things though. Could still be FP or CPS too. Although I don't think the overheating would have caused either of those two parts to fail...but doesn't mean they weren't on their way out and are causing problems now.

 

Thanks eveyone the problem was simple as replacing the CPS. A common problem I was informed when engine overheats!