Ggg
2008 V8 FSI had expansion tank rupture. I replaced with VW OEM new part (updated part number) purchased from dealer parts. Also replaced cap. Lower hose had pine hole at nipple so I shortened pipe and refitted. Leak gone.
I also cleaned everything up and washed down the motor and underside to get rid of coolant.
Drove for a few weeks with no leaks or coolant smell.
Came home and found coolant on floor again…small stream less than 1” wide by 24”. No change in coolant level still at max. No hoses show leaks. Traced to insulation between new expansion tank and plenum metal. The insulation is soaked and dripping down to floor. There are no hoses that go through this. However a few weeks ago this was soaked when the expansion tank went.
I accidentally forgot to push the overflow tube back into the fender when I installed. I found no trace of fluid in pipe or inside expansion tank under cap (visible exit).
I am stumped because 1) I am not missing any coolant. 2) what is on the floor is coolant. 3) I can see where it is coming from but there is no source in the insulation. Insulation is soaked even up to top above where anything is even located in the engine bay…so wicking up I guess from someplace.
The picture below was once everything was out but before cleanup. The insulation I am talking of is visbable front and center.
Thoughts?
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2008 V8 FSI had expansion tank rupture. I replaced with VW OEM new part (updated part number) purchased from dealer parts. Also replaced cap. Lower hose had pine hole at nipple so I shortened pipe and refitted. Leak gone.
I also cleaned everything up and washed down the motor and underside to get rid of coolant.
Drove for a few weeks with no leaks or coolant smell.
Came home and found coolant on floor again…small stream less than 1” wide by 24”. No change in coolant level still at max. No hoses show leaks. Traced to insulation between new expansion tank and plenum metal. The insulation is soaked and dripping down to floor. There are no hoses that go through this. However a few weeks ago this was soaked when the expansion tank went.
I accidentally forgot to push the overflow tube back into the fender when I installed. I found no trace of fluid in pipe or inside expansion tank under cap (visible exit).
I am stumped because 1) I am not missing any coolant. 2) what is on the floor is coolant. 3) I can see where it is coming from but there is no source in the insulation. Insulation is soaked even up to top above where anything is even located in the engine bay…so wicking up I guess from someplace.
The picture below was once everything was out but before cleanup. The insulation I am talking of is visbable front and center.
Thoughts?
