How to retro-fit the newer coolant expansion tank cap to a Mk7 Golf

[condi]

My crappy stock 2017 GTI has a click stop, works fine. Although the one Dave showed us looks good.

I've got now the one that Dave showed. It is also click-stop! You've got to use a little force to finish tightening with click!

Wysłane z mojego SM-G950F przy użyciu Tapatalka

 

[davide.bonetti]

part number 2Q0 121 321 has been superseded by 2Q0 121 321 A. apparently approx two dollars cheaper.

 

[evilhomura89]

Does anyone know if the new coolant reservoir tank from mk8 will fit on our mk7? And any idea what's the part number?
I saw a picture for a DAZA engine swap (2.0 -> 2.5) and the coolant reservoir tank that came with that engine looks exactly like the one in the mk8.

Image taken from - https://www.facebook.com/groups/TexasVWMK7golf/permalink/4739114752774401/


Mk8 engine bay

 

[evilhomura89]

Does anyone know if the new coolant reservoir tank from mk8 will fit on our mk7? And any idea what's the part number?
I saw a picture for a DAZA engine swap (2.0 -> 2.5) and the coolant reservoir tank that came with that engine looks exactly like the one in the mk8.

Image taken from - https://www.facebook.com/groups/TexasVWMK7golf/permalink/4739114752774401/
View attachment 223520

Mk8 engine bay

Found the part number:
It's probably 5WA121407C, 5WA121407E or 5WA121407F

Side by side comparison

 

[evilhomura89]

Just more information i've obtained online ETKA here - https://ifinterface.com/
After studying the diagram, the hose clamp size is identical for both mk7 and mk8 hence I believe the mk8 coolant expansion tank is compatible with mk7 as long as the clips location are correct

 

[evilhomura89]

mk8 coolant tank retrofit

My old tank is due for replacement as it still has the silica bag in it and it was really filthy in there

No amount of coolant flush is able to clean them out, hence a replacement tank is highly recommended

I came across this retrofit in the fb post shared earlier but I'm not sure if there's any benefits in retrofitting the mk8 coolant tank (other than the visual change)
And it looked nice to me so I thought why not?

Here's the result:

These are the parts required other than fresh coolants:

5WA121407F - mk8 coolant reservoir tank
2Q0121321A - coolant tank cap
5WA121447 - coolant hose top for mk8 reservoir tank
5WA121109D - coolant hose bottom

I bought the Chinese market equivalent from taobao as they're cheaper and easier to obtain for me in terms of logistics:
5WD121407A - mk8 coolant reservoir tank
2QD121321 - coolant tank cap
5WD121447 - coolant hose top for mk8 reservoir tank
5WD122109A - coolant hose bottom

Few things to take note:
1. The top hose replacement is required as the vent outlet position is different from the original tank
2. The old bottom hose fits the new tank but I replaced it anyway as the position of the notch on the hose is different. The notch on the tank is located at the bottom, but the old hose has the notch at the top position
3. You can reuse the old hose clamps as they are same sized
4. You'll need to slightly pull the sensor connector away from the wire harness to reach the connector on the new tank

Pictured below is the old hose and the notch on the bottom of the new tank



feel free to ask if you have any questions regarding this retrofit

 

[golfdave]

mk8 coolant tank retrofit

My old tank is due for replacement as it still has the silica bag in it and it was really filthy in there
View attachment 226795View attachment 226796
No amount of coolant flush is able to clean them out, hence a replacement tank is highly recommended

I came across this retrofit in the fb post shared earlier but I'm not sure if there's any benefits in retrofitting the mk8 coolant tank (other than the visual change)
And it looked nice to me so I thought why not?

Here's the result:

View attachment 226792

These are the parts required other than fresh coolants:

5WA121407F - mk8 coolant reservoir tank
2Q0121321A - coolant tank cap
5WA121447 - coolant hose top for mk8 reservoir tank
5WA121109D - coolant hose bottom

I bought the Chinese market equivalent from taobao as they're cheaper and easier to obtain for me in terms of logistics:
5WD121407A - mk8 coolant reservoir tank
2QD121321 - coolant tank cap
5WD121447 - coolant hose top for mk8 reservoir tank
5WD122109A - coolant hose bottom

Few things to take note:
1. The top hose replacement is required as the vent outlet position is different from the original tank
2. The old bottom hose fits the new tank but I replaced it anyway as the position of the notch on the hose is different. The notch on the tank is located at the bottom, but the old hose has the notch at the top position
3. You can reuse the old hose clamps as they are same sized
4. You'll need to slightly pull the sensor connector away from the wire harness to reach the connector on the new tank

Pictured below is the old hose and the notch on the bottom of the new tank
View attachment 226793View attachment 226794


feel free to ask if you have any questions regarding this retrofit

Decent write up & mod.....

You'd be better off creating your own thread as otherwise your mod only gets found under this thread title which was just a short one on swapping the cap only....I don't mind it staying in this thread...but it may get found better on its own that's all..