Coolant expansion tank ... ARGH!!!

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My last car was a Seat Leon. Coolant expansion tank, essentially a plastic ball, sat nice and proud at the top of the engine bay. Easy to read the level.

My new (to me) car, 2015 Honda Civic, has a long narrow tank (see pic below) that's crammed away down in the depths of the engine bay. Nigh on impossible to see the level. I tried buying one of those extendable bendy lights to see if that would help. Nope. I've seen others online rant about the stupid placement of this component.

Yes I can take the rad cap off and check level. However I check the levels quite regularly and I'm reluctant to take that cap on/off. Yes I can wait until a warning light comes on. Not ideal. Yes it's 'only the expansion tank' however it's always been an easy way to check coolant level. Until now :(

Stupid stupid design. Imagine this crammed in the engine bay tightly surrounded by other stuff!

collant expansion tank.jpg
 
Yes I can take the rad cap off and check level.
No, you can’t. With that setup, the water level in the radiator should always be at the very top. It’s 11 years old. It’s weathered. Get a new tank that you can see through, like you could do when it was new.
 
No, you can’t. With that setup, the water level in the radiator should always be at the very top. It’s 11 years old. It’s weathered. Get a new tank that you can see through, like you could do when it was new.
?

Yes I can. There's a rad cap at the top I can remove to check it's at the brim.
 
Just a point of (hopefully) interest regarding the typical Honda cooling system.
The main radiator cap is a two way design - unlike the typical ones that only let excess coolant out, this type lets it back again.
The main radiator must always remain brim full. The expansion bottle must have enough fluid in it to completely cover the dip pipe rubber hose.
So, the coolant expands, and passes to the expansion bottle. On cooling down, the coolant is sucked back into the rad.
Obviously, the levels I've mentioned are critical to the correct performance of the cooling system.
Regards
John :)
 
Just a point of (hopefully) interest regarding the typical Honda cooling system.
The main radiator cap is a two way design - unlike the typical ones that only let excess coolant out, this type lets it back again.
The main radiator must always remain brim full. The expansion bottle must have enough fluid in it to completely cover the dip pipe rubber hose.
So, the coolant expands, and passes to the expansion bottle. On cooling down, the coolant is sucked back into the rad.
Obviously, the levels I've mentioned are critical to the correct performance of the cooling system.
Regards
John :)
Yeah this is what I'm doing for now, taking rad cap off and ensuring brim full. Thanks for the additional info :)
 
Just fill the expansion bottle up to the max. You can’t really overfill that type of setup. It’ll discharge what it doesn’t need when the engine reaches working temperature.
 
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