Fan moving in and out- bad water pump bearing? (also noise)

[StephenL]

Would welcome wisdom to guide me

Symptom is a nasty intermittent knock/grinding noise on 2001 4.0 Sport Trac

I replaced the idler pulley and the tensioner. Bearings on both were not special, so no regrets on that, but it hasn't solved the problem.

I've put an ear against a long screwdriver touching the alternator, ac compressor and steering bodies, I can't really pin it down to one of those, all about the same volume. Same goes for the water pump BUT the pump and the fan are moving in and out between the block and the radiator ever so slightly. That doesn't seem right to me, so I'm going in for a water pump replacement thinking the water pump bearing is shot. Vesicles has 257k miles, no idea if it is the original pump but I've had it since 215k

What do you think? TIA

 

[swshawaii]

With the engine cold, remove the belt and start. Listen carefully for noises from the belt driven components. If nothing is heard, place the screwdriver tip on the front of the driver valve cover and rear of the passenger valve cover. Also the primary timing chain in the front center. Possibly a broken plastic timing chain guide causing chain slap, especially at cold startup. Do not run the engine too long without the belt or the engine will overheat.

 

[StephenL]

Thank you for your reply. I think I've solved the mystery as even though I ordered the parts I needed the car for one last trip before they arrived. The water pump seized, shredding the belt, damaging the wiring to the MAF sensor (wrapped around the alternator pulley). its very clear now the water pump bearing isn't the best.....

 

[StephenL]

Here is the bundle of wires that went to my MAP sensor and got wrapped around the alternator pulley. Pretty terminal.

Since the above plea and update, I have been to a junkyard to get a replacement section of loom off a scrap car and soldered it in. I've also replaced the water pump and got everything put back together

So in theory I should be good to go. But , the engine won't crank. Nothing. I can't see any other damage from the shredded belt that can explain it. I've checked all the fuses and the starter relay is NOT getting power when the key is turned.


I can't think what has caused this. it could be lots of things but it must be related to this incident as it was fine before. The thick red wire, probably a live, above has probable touched the alternator pulley, which isn't good, but I'd like to think it would have blown a fuse.

Maybe this has something to do with the PATs security system, maybe from being towed or how did this belt issue screw it up??


I'd be grateful for any suggestions as I'm out!

 

[oknopa]

I just remember, when my trac wouldn't start is was the ignition switch. Maybe take a look.

 

[StephenL]

Thank you, I've got further into this and found some good stuff that may help others
-The starter relay is fed a live and a ground by 2 sperate circuits
The live circuit goes through the ignition and switch on the transmission that ensures the car is in park or neutral. If either of then are bad then it won';t provide the live
The ground circuit is the PATS system (the chip in the key) and anti theft, via the PCM

So I tested the live on the relay socket, which is under the hood between the battery and the driver. When key was turned, I got a live which tells me all that is OK

The ground was not being provided though. When I ran a wire from the battery ground to that socket and pushed the relay back in, the car cranked, but would not start.

This tells me the fuel/spark are not being provided too so I have moved on to that. Because its not just the starter impacted I am going to do some tests on the PCM. My suspicion right now is that the PCM got some shorts when the wires in the picture above got shredded and is toasted.

 

[StephenL]

To close this out that was the problem. Bad PCM shorted when the wires were damaged

 

[DILLARD000]

Do keep us updated on how it goes, assuming you're now replacing PCM.
Consider renewing the 2 OilPressurized TimngTensioners, needed every 100kMiles\12yrs,
if not already done, or you don't know.