# Questions about cooling system

**URL:** <https://community.cartalk.com/t/questions-about-cooling-system/108766>\
**Category:** Maintenance/Repairs\
**Tags:** hyundai, tucson\
**Created:** [October 20, 2017, 9:10pm UTC](https://community.cartalk.com/t/questions-about-cooling-system/108766 "2017-10-20T21:10:37Z")\
**Posts on this page:** 6\
**Page:** 2

<div class="post-metadata">

**Author:** ![TheMidnightNarwhal](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/themidnightnarwhal/32/5375_2.png) [@TheMidnightNarwhal](https://community.cartalk.com/u/TheMidnightNarwhal)\
**Post date:** [October 21, 2017, 9:06pm UTC](https://community.cartalk.com/t/questions-about-cooling-system/108766/21 "2017-10-21T21:06:09Z")

</div>

In the manual tells you how to do it.

Fill rad until no more goes in. Start the engine. Do the same until no more goes in and fill the overflow tank. I’ll also try squeezing the upper hose to that helps bleeding to.

---

<div class="post-metadata">

**Author:** ![common-sense-answer](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/common-sense-answer/32/716_2.png) [@common-sense-answer](https://community.cartalk.com/u/common-sense-answer)\
**Post date:** [October 21, 2017, 9:10pm UTC](https://community.cartalk.com/t/questions-about-cooling-system/108766/22 "2017-10-21T21:10:40Z")

</div>

> [@TheMidnightNarwhal](#):
>
> In the manual tells you how to do it.
> 
> Fill rad until no more goes in. Start the engine. Do the same until no more goes in and fill the overflow tank. I’ll also try squeezing the upper hose to that helps bleeding to.

It sounds like a plan! 🙂  
_ **CSA** _

---

<div class="post-metadata">

**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\
**Post date:** [October 21, 2017, 11:17pm UTC](https://community.cartalk.com/t/questions-about-cooling-system/108766/23 "2017-10-21T23:17:20Z")

</div>

Sometimes the tubes between the radiator cap area and the overflow plastic tanks, and from the tank to the final overflow tube, can clog up and create weird symptoms, including leaks. Make sure they are all open and clear of debris and clogs. I expect you already know this, but the only way to be certain the cooling system is filled is by filling both the overflow tank and the radiator. If you have a small leak in the cooling system the radiator can be nearly out of coolant while the overflow tank still has coolant in it. Faulty radiator caps are a pretty common thing reported here, and can create weird symptoms, so that’s another avenue for your diagnostics. Most people just replace them if they’re suspect, but I think shops can test the radiator cap itself to verify it holds pressure to a certain psi, then opens like it should. It’s just a spring loaded valve arrangement I think.

---

<div class="post-metadata">

**Author:** ![Purebred](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/purebred/32/46796_2.png) [@Purebred](https://community.cartalk.com/u/Purebred)\
**Post date:** [October 22, 2017, 1:18am UTC](https://community.cartalk.com/t/questions-about-cooling-system/108766/24 "2017-10-22T01:18:44Z")

</div>

Since you have a cap on the radiator, add until full, with the cap OFF, run engine until the engine is warm enough to open the thermostat. You should be able to see the coolant circulating, then top it off, have heater ON. when fully topped off reinstall cap. With what you have described you will probably see the leak then.

---

<div class="post-metadata">

**Author:** ![TheMidnightNarwhal](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/themidnightnarwhal/32/5375_2.png) [@TheMidnightNarwhal](https://community.cartalk.com/u/TheMidnightNarwhal)\
**Post date:** [October 25, 2017, 4:47pm UTC](https://community.cartalk.com/t/questions-about-cooling-system/108766/25 "2017-10-25T16:47:06Z")

</div>

If anyone interested, filled it up about 3 days ago and ever since all the mornings the rad is still at the top and overflow tank stays a the right level.

---

<div class="post-metadata">

**Author:** ![George\_San\_Jose1](https://avatars.discourse-cdn.com/v4/letter/g/e5b9ba/32.png) [@George\_San\_Jose1](https://community.cartalk.com/u/George_San_Jose1)\
**Post date:** [October 26, 2017, 12:04am UTC](https://community.cartalk.com/t/questions-about-cooling-system/108766/26 "2017-10-26T00:04:37Z")

</div>

Good for you. Sounds like it is _all systems go_.

[Previous page](https://community.cartalk.com/t/questions-about-cooling-system/108766.md?page=1)