3.0t coolant vs. PCV valve

[ELaw]

Folks,

I pulled the supercharger off my 3.0t to install a smaller pulley, and preventively replace some parts that are underneath it, including the PCV valve or whatever it's officially called.

Something I read on the 'net implied that removing the PCV valve would spill coolant into the oil, requiring the oil to be changed. Does anyone know if that's 1) true at all and 2) true even if the coolant has been completely drained?

Thanks!

[gk1]

I think I read the same as you where someone's oil separator failed and leaked coolant.


In this pic it looks like the main integrated pipes in the top of the oil separator carry coolant. I don't have the Audi coolant flow diagram for the 3.0T.


I don't know for sure if you have drained all the coolant if that area is then emptied. Hopefully someone else can chime in.

[ELaw]

Yeah I was looking at some diagrams and photos and came to the same conclusion. It looks like in their infinite wisdom, Audi uses the PCV valve to carry the coolant from the water pump outlet to the two cylinder banks!

I'm hoping that since I drained the coolant pretty well there will be little if any left over in those passages. But if the coolant were full I can see a disaster happening if you remove the valve.

[Valpo A7]

If the oil looks like chocolate milk when you fire it back up then you know you got coolant in the oil and its time for an oil change. OR go ahead and change oil now and consider the $50 of oil as cheap insurance.

[quattroism25]

Folks,

I pulled the supercharger off my 3.0t to install a smaller pulley, and preventively replace some parts that are underneath it, including the PCV valve or whatever it's officially called.

Something I read on the 'net implied that removing the PCV valve would spill coolant into the oil, requiring the oil to be changed. Does anyone know if that's 1) true at all and 2) true even if the coolant has been completely drained?

Thanks!

Do you have DIY for the PCV valve? What other parts did you replace with the supercharger off?

[ELaw]

I don't think I could make up a "DIY" for it as I didn't keep very careful notes, but the general idea is "keep removing stuff from the top of the engine until you can get to the PCV assembly, replace it, then put all the stuff back". ;^)

I think the thing that might generate the most questions is which lower intake mainfold(s) you need to remove to get the PCV out. The service manual says you only need to remove the left one (viewed from the front of the car) but when I got to that point I realized I had so much stuff off I might as well take the right one off also and clean the carbon off the valves. Oh and I've heard tales from exotic foreign lands of people removing intake manifolds from the engine and having the injectors stay in the head(s), but between my (B8) A4 and this car I've had 10 out of 10 injectors come out with the fuel fail, necessitating changing the seals on said injectors. I worried a lot about a tool kit to change the seals, as I had bought the one from ECS that's intended to work on my (4-cylinder) A4 but they don't say it will work for the 3.0t, and very few people seem to sell kits that work with the 3.0 engine. The face of the little "cone" tool to expand the seal didn't mate to the front of the injectors perfectly, but it was the right size and ultimately the tool did work with little difficulty.

What I replaced? The "reason" for the project was to replace the supercharger pulley with a smaller one (which I know can be done on the car but taking the SC off provided an excuse to do the other stuff). I also replaced the thermostat, water pump (which you don't need the SC off to do but it does make it easier), serpentine belt idler pulley, both serpentine belts (accessory and supercharger), the plastic coolant line running from the thermostat housing to the hose going to the heater core in the back, the crankcase vent tube that connects the PCV assembly to the valve covers, and the PCV assembly.

I changed the coolant since it needed to be drained anyway, and even though the system was drained, it did appear a little coolant got into the crankcase as a result of removing the PCV unit. So being "better safe than sorry" I changed the oil.

Interestingly, although I wasn't aware of it, the water pump did have a problem. The pump actually has a clutch in it that's vacuum-actuated. Although I was going to replace it anyway, before I pulled it off I put a vacuum tester on the line feeding the clutch and it would not hold vacuum. With the pump replaced, the car actually seems to warm up faster.

[quattroism25]

I don't think I could make up a "DIY" for it as I didn't keep very careful notes, but the general idea is "keep removing stuff from the top of the engine until you can get to the PCV assembly, replace it, then put all the stuff back". ;^)

I think the thing that might generate the most questions is which lower intake mainfold(s) you need to remove to get the PCV out. The service manual says you only need to remove the left one (viewed from the front of the car) but when I got to that point I realized I had so much stuff off I might as well take the right one off also and clean the carbon off the valves. Oh and I've heard tales from exotic foreign lands of people removing intake manifolds from the engine and having the injectors stay in the head(s), but between my (B8) A4 and this car I've had 10 out of 10 injectors come out with the fuel fail, necessitating changing the seals on said injectors. I worried a lot about a tool kit to change the seals, as I had bought the one from ECS that's intended to work on my (4-cylinder) A4 but they don't say it will work for the 3.0t, and very few people seem to sell kits that work with the 3.0 engine. The face of the little "cone" tool to expand the seal didn't mate to the front of the injectors perfectly, but it was the right size and ultimately the tool did work with little difficulty.

What I replaced? The "reason" for the project was to replace the supercharger pulley with a smaller one (which I know can be done on the car but taking the SC off provided an excuse to do the other stuff). I also replaced the thermostat, water pump (which you don't need the SC off to do but it does make it easier), serpentine belt idler pulley, both serpentine belts (accessory and supercharger), the plastic coolant line running from the thermostat housing to the hose going to the heater core in the back, the crankcase vent tube that connects the PCV assembly to the valve covers, and the PCV assembly.

I changed the coolant since it needed to be drained anyway, and even though the system was drained, it did appear a little coolant got into the crankcase as a result of removing the PCV unit. So being "better safe than sorry" I changed the oil.

Interestingly, although I wasn't aware of it, the water pump did have a problem. The pump actually has a clutch in it that's vacuum-actuated. Although I was going to replace it anyway, before I pulled it off I put a vacuum tester on the line feeding the clutch and it would not hold vacuum. With the pump replaced, the car actually seems to warm up faster.

Interesting...So far I've gathered these parts. Breather hoses will be optional, depending on their condition.


https://www.fcpeuro.com/products/aud...t-06e103547hkt

https://www.fcpeuro.com/products/aud...raf-06e121018k

https://www.fcpeuro.com/products/vw-...vw-06e103217ad

https://www.fcpeuro.com/products/vw-...vw-06e103207ap

[ELaw]

Cool!

I didn't replace your last item but did replace:

06E-121-111-AL Engine Coolant Thermostat Kit
06E-121-065-N Connector Pipe
and
06E-121-045-BB Water Pipe

The last one I forgot when I wrote the post above, it's the coolant crossover pipe that attaches to the heads on the front of the engine.

I also ordered a number of o-rings that I didn't end up using as all the parts that used them (coolant pipes) came with them.

[Valpo A7]

Here is a link to part of the DIY. This will get you to the t-stat and water pump

https://www.audizine.com/forum/showt...Removed-(Pics)


Video: https://www.youtube.com/watch?v=xyZL...ature=youtu.be