Ok, there's the cap on the AST, there's one called the filler cap (near thermostat) and one that has a long dipstick attached to it. So what are the differences and which do I remove to check coolant level and which to fill with more coolant?

Thanks,

Ant

 

The one that has the dipstick is called the overflow tank. You dont have to add water or coolant to the overflow tank. You can, but it's not necessary. Water/coolant can be added to the filler neck and the AST. As for the coolant level, you can check all of them, the overflow tank, filler neck and AST.

 

from what i know, you never want to take the AST cap off. it even says right on top of the stock cap.

 

The AST cap is a pressure cap. The filler neck is plain no-pressure cap. When refilling the system with coolant it helps to open the AST cap because it allows some of the air to evacuate.

 

When I checked my overflow tank dipstick, it looked like someone put it up their ***. I mean there was this brown algae on the submerged end of the dipstick. WTF was it? Has anybody else had this experience?

 

When was it changed last? Doesn't matter...change it.
Could it be oil?

 

Read more carefully. It says "do not remove when hot".

BTW, I have gunk in my overflow tank too. There's another current thread about this issue. A couple of experienced FD owners (Max Cooper for example) say they have never seen an FD without gunk in the overflow tank.

 

Thanks ferllers. I got that light brownish gunk on my dipstick too. Anyone know where that other thread is?

Ant

 

Hmmm...I've never seen it, but then again I'm not sneaking around in the parking lots to check. Even if it is common, I'd flush it.

 

https://www.rx7club.com/forum/showth...threadid=67949

 

That's the other thread.

 

Here's the thread about the dirt in the coolant:

https://www.rx7club.com/forum/showth...threadid=67949

EDIT: DOH! Late again....