TDI AHU: Replacing Water Hoses - Tips & Tricks

Hello.
My Golf 3 TDI with the AHU engine has never let me down in the last 400,000 km, and I want to keep it that way. All the hoses and lines are still original, so I figured it's time to replace them.

"I'm now planning to completely renovate the entire cooling system, ideally using original parts. Unfortunately, the water flange with part number ZK 028121132A is no longer available."
"068121132A is still available, can anyone tell me if it's compatible?"
Also, also the flange for pump 037 121 121 A as well.


If there's absolutely no other option, which manufacturer would you recommend for these components? Or, if they still look reasonably good, which ones should we consider?

What should be done regarding the oil cooler?
Is the sealing to the block a problem? Currently, it doesn't appear to be a leak, but it might be worth investigating.



"Thank you."

Hello,

068121132A does not fit. This part is for the AAZ engine - the screw mountings are different here.

If you can't find anything else at VW Classicparts, I would go with FEBI or Meyle.

Best regards,

Michael.

Hello.
Thanks for the information. Unfortunately, the part number 028121132A is also no longer available at Classic Parts, only the 068121132A. That's why I asked if the latter might also be compatible.
"I noticed during the lengthwise installation, specifically for a 1Z B4 engine, that there was an aluminum flange with part number 028121133A. Would it be possible to obtain one that fits?"

"Thank you."

Hello,

If the engine has freeze plugs, apply a generous amount of copper paste (especially if they are already rusty) or anti-rust treatment to them. Otherwise, these metal pieces will eventually corrode through, and you will suddenly lose your coolant.

Best regards, Rainer.

The engine, and those can also be replaced. If there is rust, even Cu cream won't help anymore .
hg
Herbert.

PS: The main wear components in this engine, considering its mileage, are the hydraulic lifters, the crankshaft seals, and the camshaft.

Thanks for the tips. Is there a list or overview showing where the plugs are located?
So far, only one person has stood out at the WAPU.

I think the other points are unremarkable. Shaft seals would cause noticeable oil consumption, but he doesn't have that problem.
Hydraulic lifters: They don't rattle during cold starts, or can they also wear out under other circumstances?
Camshaft? Does it work properly? Or can you check something there?

bindpe wrote:

Thank you for the tips, is there a list showing where the plugs are located? --> #1 So far, only one person has stood out at the WAPU. The other points, I think, are unremarkable. Shaft seals would cause noticeable oil consumption, but he doesn't have any. --> #2 Hydraulic lifters, during cold starts, there's no rattling, or can they also be worn out otherwise? --> #3 Camshaft? Does it run? Or can something be checked there? --> #4

#1: one for each cylinder, preferably located on the exhaust side and hidden.
#2: not necessarily;
#3: The surfaces that are primarily under stress are likely to fracture. Visible pitting is a clear indication of this.
#4: Material loss/grooves and hairline cracks on the cam lobes.

Try using the search function; this has been posted before.
hg
Herbert.

Thank you for the tips.
What are your thoughts regarding the oil cooler?
Is the distance to the block a problem?
Should I just replace it, or should I leave it alone if there's no leak?

If your car breaks down, there's a high probability that it's due to your pointless tinkering. X

Replacing dense poetry... sure, you could also dig in my garden, that would be more useful.

dieselschrauber wrote:

If your car breaks down, there's a high probability that it's due to your pointless tinkering. X Replacing dense poetry... sure, you could also dig in my garden, that would be more sensible.

It's easy to say, but not always easy to do... Seals are less of a problem, but form-fitting hoses can become very difficult to source, and sometimes they are simply no longer available. I'm currently experiencing this problem with an older 16V engine that needs to be rebuilt.
Since you're already at it, and as long as the parts are still available, I would recommend replacing them directly.