[gkamieneski]

I notice 2 reservoirs to the right-side of my 430i x-drive CV. One is a large reservoir with a larger cap and that appears to be the expansion tank. With a lot of effort I was able to loosen the cap and see by the inside gauge that coolant is at max level.

Now the smaller reservoir, I cannot even get my hands in enough to get enough torque to loosen the cap. What is this reservoir and do I need to be checking it as well?

[gkamieneski]

O.K. so I have learned that the smaller tank is an air charge cooler for the manifold.

Now the question is how to open the cap? I tried rubber gloves and bare hands put I just can't get a purchase on the cap as it is surrounded by the regular coolant reservoir an other structural components in the engine bay.

Does anyone have a trick for opening this small cap?

[Sweeney921]

Grip strength

[gkamieneski]

Thanks. Finally got it. I had to use a kitchen grip to get enough purchase on it in such a tight space, with large hands.