Best way to clean water pump housing on the 1.8?

[AJ97]

Long story short, on my 2004 A4 1.8T I went to do the timing belt back in December. Figured I’d replace the pump while I was in there. Turns out I did it incorrectly and now have a coolant leak. After researching a bit I think my mistake was not putting the pump in by hand, instead tightening down the bolts a half a turn at a time until it was fully seated. Guess this causes the O-ring to become damaged. Well I have the car apart again, at the point where I’ve removed the middle timing cover and have the carrier slid out enough to work on. I need to get the coolant drained, and remove the tensioner so I can pull the pump out again, but what’s the best method for cleaning the pumps mating surface. Last time I sat there with green scotch pads and carb cleaner for hours. I got most of it off but still had a bit of scaling on the inside where the o-ring sits. I want to make sure I do this 100% correct because I DO NOT want to do this job again lol. Hoping to be able to reuse the hydraulic tensioner by putting it back in with a c-clamp, think I still have the pin laying around somewhere. I’m REALLY hoping not to have to take off the harmonic balancer (?) off the crank. That was a huge pain last time since I’m not completely removing the carrier.


But My biggest questions still is what’s the best method or materials for cleaning the water pump housing? Thanks!

[BARRY]

scotch bright, steel wool, emory cloth, or sand paper. just make sure to not get any material inside. stuff a rag into the hole first to help protect.

[Biged243]

Wire brush also does the trick

[AJ97]

Oh boy has this been fun. So I first tried again with the scotch pads. Had no luck. So I tried one of those 3M “medium” sponge sanding blocks from Lowe’s. Didn’t really do much either. So I went to the store again and got some steel wool and those stainless steel scrubbing pads. Neither of those did anything. So once again off to the hardware store. Picked up some 2000 grit sand paper. Seems to be working a lot better but still needs a lot of effort to get it all off. What a PITA it is just to clean the surface! Taking a break after scrubbing for 2 hours. Really hoping this sand paper will do the trick.

[AJ97]

I finally was able to clean off almost everything on the mounting surface, cleaned the pump up again, and put it in with a small beed of sealant around the block. However now I’m having an issue with the hydraulic tensioner extending all the way out when rotating the engine clockwise a full turn. I set the proper tension at 8MM, then tighten the nut on the roller to 20 foot LBS. Everything stayed perfect until I rotate the engine and the tensioner expands almost all the way. The gap is more like 12mm now. I tried again 2 times and the same thing keeps happening. Is this a bad roller tensioner? Is it fine to have it extended all the way?

[BARRY]

not possible unless installed wrong.

[AJ97]

not possible unless installed wrong.

I’ve double checked everything, and tried again two more times. Not sure what’s wrong. Every time I get the tensioner set properly and go to rotate the engine over, the tensioner fully expands. The roller seems to be functioning properly, but I have a feeling that it might be broken if it’s not keeping the tension. Could it also be due to the fact that the t-belt is already 6-7k miles used? So it’s more stretched out and the tensioner is picking up the slack? Please help, I need to get this car finished ASAP!


Thanks!

[BARRY]

please post picture...what you describe is not possible if everything is installed correctly...or your belt is stretched? belts last 80-120k miles before failing on these engines.

[AJ97]

please post picture...what you describe is not possible if everything is installed correctly...or your belt is stretched? belts last 80-120k miles before failing on these engines.

http://i.imgur.com/Pl4QJno.jpg

Apparently can’t figure out how to post an imagine on here lol

For comparison that’s an 8mm Socket.

This is the best I could get considering I didn’t fully remove the full carrier.

[EuroxS4]

http://i.imgur.com/Pl4QJno.jpg

Apparently can’t figure out how to post an imagine on here lol

For comparison that’s an 8mm Socket.

This is the best I could get considering I didn’t fully remove the full carrier.

Thats a old setup. Get rid of that useless horrible design and go to the litens design. Roller tensioner in 1. So much better than they hydralic garbage. Yes it looks weird possibly over tensioned , the gap should be less than that IIRC. Should be able to fit a 6mm hex in there. Also IIRC you had to pretension those pull the key for the tensioner and then tighten the 13 or 10mm nut.

[BARRY]

do you have a farther picture? i believe your pulley is on incorrectly. the hydraulic tensioner works great if you are not high horsepower or reving the engine past 7,500rpm constantly.

the pulley is offset and needs to be installed in the correct orientation.

https://www.pelicanparts.com/techart...eplacement.htm




https://www.audizine.com/forum/showt...er-Pump-Change

[AJ97]

The problem I think was the metal tab on the roller. Like mentioned above it needs to be positioned exactly as it is above. Rotated the engine and it stayed below 10mm. Closed everything up, filled the coolant and started it up. Everything seemed fine. Stoped it after a few minutes and pulled the top timing cover and checked the gap. Now it was around 6-7mm. Perfect. Well I go drive it around maybe 3 miles, get home and park it. Look for leaks and see a small puddle on the back passenger side of the engine bay. Nothing to bad. Go to back it in my driveway and it starts gushing. Lost probably a quart and a half just backing it into my garage. Same spot, back passenger side of the bay.

Looking around the top of the engine I see it wet on the top of the transmission, and I see some moisture on the drivers side under in the intake manifold. I don’t think it’s the coolant flange is it? When I bought the car a year ago they replaced that before I bought it. Thermostat and j-plug maybe? Such a pain. I had no major coolant leak except from the pump before this repair and now it’s just gushing coolant.

[walky_talky20]

The problem I think was the metal tab on the roller. Like mentioned above it needs to be positioned exactly as it is above.

It's not that there is one "correct" position. That tab is a fully variable adjustment for the eccentric and it needs to be adjusted correctly at time of install. This process is kind of difficult to explain in text and is often done incorrectly or skipped, even by actual technicians. This is why I always suggest using the updated "Litens" tensioner in all cases where this eccentric/hydraulic setup would have previously been used. The Litens version ditches the hydraulic altogether and uses a spring loaded eccentric with a really easy "point and shoot" tension adjustment mechanism.

[AJ97]

I wish I could just drive this car again! Urgh. So I looked over my documents from when I bought the car last year, I knew they replaced the coolant flange but I wanted to double check. It says they replaced the flange and the thermostat. So I ended up calling a tow truck and had them take it a firestone down the street. They did a compression test and called me back saying it was the heater core line on the back of the engine. Wanted over $500 to do it *eye roll*. They also claimed that the AC system would need to be drained in order to do it. I went and paid the diagnostic fee and got the keys. Waiting for the tow truck to bring it back to my house now. A shop about 25 miles from me is willing to do the job for $205 with labor and parts, and they specialize in Audi/VW. So now I’m stuck with either doing the work myself or getting a tow truck for $50 and paying the $205 service charge. How difficult is it really to get back there? Is it something that’s not a huge PITA? I would love to save money but my back is killing me from working on this car.

[kwilson]

If you can do a timing belt, you can do a coolant flange. You'll be happy that you saved $200.

[BARRY]

the most difficult thing to do on the 1.8t is the rear coolant flange. everything else is SUPER EASY. just takes time to do it anything else right. oh and installing a turbo inlet pipe is a pain due to spacing. oh and maybe timing chain tensioner, but after doing it 3 times...its really easy.

[Gosser]

I can do a coolant flange in my sleep now. Its just a a matter of not cutting corners, and removing all the stuff that’s in the way, and that includes the combi valve.