01 - a6 quattro 2.7t - 145,000 miles

my alternator went out about a week ago - as car was no longer charging the battery. funds are tight, so i've been limping along with a battery charger & spare battery. getting couple hundred miles between swapping battery and charging at night. en route home one day, about 2 miles out, the car overheated with a large amount of steam spewing from center of engine area. i let car cool overnight and drove home the next morning with nothing out of ordinay - except for overheating due to lack of water/coolant - if i had driven that long. no noises out of ordinary on final trip home

i found that it was the aux water pump that blew out from the front area (where water enters and exits). replacing this took a couple days, in that time my son turned the engine over whilst a 3/8" wrench had fallen into main fan blade area - this kicked the wrench up & subsequently knocked of the serp belt.

in reading what others posted in the forum i mistook what was required to get the serp belt back on track as i tried using an 8 mm allen turning the inside of the bolt used to releive pressure from the serp belt tensioner. in reality i found that it was the 17mm socket (on the outside) needed to loosen the tensioner and allow putting the serp back on. which i eventually figured out.

inspection of the immediate area & serp belt showed no obvious signs of damage and thought i may have escaped unscathed - though after putting car back together and starting i heard a loud screeching noise coming from what seemed to be the main water pump and/or area (at top of engine behind turbo air intakes). when i turn the wheel i hear loud noise from serp belt/top of engine area & feel a sticky/jittery movement from power steering.

my wife has an 02 a6 allroad quattro 2.7t nearly idetical to mine. her serp belt seems to not be as tight as mine. not sure if whilst using the 8 mm allen i tightened my belt up? though i read it's an auto tensioner which would make me believe that's not possible.

any direction/help would be much appreciated.

thank you

 

I don't know about giving directions, but you may have two scenarios, from which one may be or not related to the wrench knocking off the ribbed belt.

The main water pump is driven by the timing belt, so more likely has nothing in common with the wrench incident, but it may have some relationship with the overheating. Maybe its bearing/pulley seized. I doubt you have one with a plastic impeller (old style) judging by the year of the car, but you never know. It is a possibility that it got damaged at the same time with the secondary pump. If that's the case, then the tb just runs over the pulley, rubbing against it rather than turning it. I would assume that could cause a screech.
I would remove the timing belt covers and see if the WP pulley turns.

The second possibility is that your power steering pump's pulley may be seized and the same rubbing (from the ribbed belt) is going on causing the screech. You should be able to see the pulley turning through the hole in the front engine cover. Does it turn as the engine runs?

 

i do remember looking at the water pump wheel/pulley while the engine was running yesterday and saw the wheel turning so i'm thinking it's not seized, but bad bearings is a very real possilbility. additionally i could turn the stearing wheel with ease, the noise just became much louder noise while the wheels turned. i believe the power stearing pump is working ok.

this morning i turned the engine over & heard a loud grind so i let off the key. i tried it twice more for short periods (a second or two) and felt heavy resistance from the engine - sort of like i would feel from my corvette - before i got the a6 - with it's higher compression. i'm thinking the direction i should be leaning is the timing belt. it's likely that's where the grinding would come from. i'm also thinking that is what the higher compression - what do you think?

thanks for your help