[Pnut]

Lol a supposedly simple something I never thought I would have to ask for help on... its not like its my first rodeo 

I have tried to remove the radiator cap a few times but cant seem to get it off. I can turn it counterclockwise to the first stop, but cant seem to get it any further. I have tried to push down but feel like if I push any harder I might risk damaging or breaking the neck or top of the radiator.

Am I missing something? Is there some special technique? Or do I just need to grow a pair and push on it harder than I have on any other car I've owned?

[TerryT]

...I have tried to remove the radiator cap a few times but cant seem to get it off. I can turn it counterclockwise to the first stop, but cant seem to get it any further...

Not a mechanic but maybe an answer to this question may help the experts here more quickly solve your problem.

If you turn the radiator cap counter-clockwise to the first stop and you peek under the cap (and lift up any slack), can you see if the cap tabs (A) have moved clearly into the radiator neck slots (B), on both sides.   See picture attached.



upload image

[The Gonz]

Terry's response is all I can offer. It's purely a mechanical alignment problem.

[Pnut]

Ok, as long as they arent anything special that i am fighting against and risking breaking, thats the main thing.

Going to do a full service on it in a few weeks and dont want to add a busted radiator to the list 

[TerryT]

Ok, as long as they arent anything special that i am fighting against and risking breaking, thats the main thing.

Going to do a full service on it in a few weeks and dont want to add a busted radiator to the list 

@ Pnut.  Just to clear up something.  Re the photo in my post above (and my unanswered question), when you simultaneously push down on the radiator cap and turn it counter-clockwise to the first stop, do the radiator cap TABS (A) clearly move into the SLOTS (B) in the radiator neck...or not?

A question I forgot to ask you before, have you removed this radiator cap before?  I know the car is 2011 and you apparently service your cars but you may have bought the car a week ago and this is the first time you have tried the cap.  Just trying to get some context. 

If the cap TABS (A) and neck SLOTS (B) do line up correctly on both sides and you still cannot get the cap off, it is possible that the radiator cap TABS are a tad too thick or too long to readily lift over the top LIP in the radiator neck slots.  (See photo below). You don't have the wriggle room needed to clear the radiator cap over the radiator neck top LIP...and force is needed (and/or trying to prise the tab down a touch to give the clearance needed). 

But this mis-fit normally would only happen IF the radiator cap is not a genuine "Hyundai cap" (TIC) or a quality brand cap... but is a Charlie Cheapo.  Given the age of your car, can we assume that the radiator cap is not the oem supplied cap?  Usually these 'Cheapo' radiator caps in their first fitment have to be rather forced on the radiator neck, more so than a 'qualty' cap.  Been there, done that.   

Your 'simple' problem had got me thinking, hence the interest and replying to you in detail.  I would like to know the final solution/outcome if you don't mind.  That helps us all here on the forum.  (I have no idea of your skill/experience with cars  so hope you don't think I am trying to teach you 'how to suck eggs'). 

[Pnut]

@ Pnut.  Just to clear up something.  Re the photo in my post above (and my unanswered question), when you simultaneously push down on the radiator cap and turn it counter-clockwise to the first stop, do the radiator cap TABS (A) clearly move into the SLOTS (B) in the radiator neck...or not?

A question I forgot to ask you before, have you removed this radiator cap before?  I know the car is 2011 and you apparently service your cars but you may have bought the car a week ago and this is the first time you have tried the cap.  Just trying to get some context. 

If the cap TABS (A) and neck SLOTS (B) do line up correctly on both sides and you still cannot get the cap off, it is possible that the radiator cap TABS are a tad too thick or too long to readily lift over the top LIP in the radiator neck slots.  (See photo below). You don't have the wriggle room needed to clear the radiator cap over the radiator neck top LIP...and force is needed (and/or trying to prise the tab down a touch to give the clearance needed). 

But this mis-fit normally would only happen IF the radiator cap is not a genuine "Hyundai cap" (TIC) or a quality brand cap... but is a Charlie Cheapo.  Given the age of your car, can we assume that the radiator cap is not the oem supplied cap?  Usually these 'Cheapo' radiator caps in their first fitment have to be rather forced on the radiator neck, more so than a 'qualty' cap.  Been there, done that.   

Your 'simple' problem had got me thinking, hence the interest and replying to you in detail.  I would like to know the final solution/outcome if you don't mind.  That helps us all here on the forum.  (I have no idea of your skill/experience with cars  so hope you don't think I am trying to teach you 'how to suck eggs'). 

I am a mechanical engineer by trade and have been working on cars since before i got my license, but that said i am no expert so appreciate any help and knowledge i can get from everyone. Things change, designs change, manufacturers have different ways of skinning cat, so I dont know if im missing something. Thats why we are all here right? To learn and help.

The cars newish to us, bought it to replace the wifes car a month or 2 ago, so this will be the first service by me. It looks like it has been serviced semi regularly by the service book, and looking at the oil colour and other items it looks like it has been cared for. That said i dont know when the last time the cap was taken off, i am pretty sure it is OEM (probably still original) going from memory. The plan was to change the coolant while i am at it so i know all the fluids and filters are new going forward. I will keep an eye out for the tabs when i go to look at it next, like i said its the wifes car so i dont see it that often to check. Will let you knw when i do 

[TerryT]

@ Pnut.  Just to clear up something.  Re the photo in my post above (and my unanswered question), when you simultaneously push down on the radiator cap and turn it counter-clockwise to the first stop, do the radiator cap TABS (A) clearly move into the SLOTS (B) in the radiator neck...or not?

A question I forgot to ask you before, have you removed this radiator cap before?  I know the car is 2011 and you apparently service your cars but you may have bought the car a week ago and this is the first time you have tried the cap.  Just trying to get some context. 

If the cap TABS (A) and neck SLOTS (B) do line up correctly on both sides and you still cannot get the cap off, it is possible that the radiator cap TABS are a tad too thick or too long to readily lift over the top LIP in the radiator neck slots.  (See photo below). You don't have the wriggle room needed to clear the radiator cap over the radiator neck top LIP...and force is needed (and/or trying to prise the tab down a touch to give the clearance needed). 

But this mis-fit normally would only happen IF the radiator cap is not a genuine "Hyundai cap" (TIC) or a quality brand cap... but is a Charlie Cheapo.  Given the age of your car, can we assume that the radiator cap is not the oem supplied cap?  Usually these 'Cheapo' radiator caps in their first fitment have to be rather forced on the radiator neck, more so than a 'quailty' cap.  Been there, done that.   

Your 'simple' problem had got me thinking, hence the interest and replying to you in detail.  I would like to know the final solution/outcome if you don't mind.  That helps us all here on the forum.  (I have no idea of your skill/experience with cars  so hope you don't think I am trying to teach you 'how to suck eggs'). 

I am a mechanical engineer by trade and have been working on cars since before i got my license, but that said i am no expert so appreciate any help and knowledge i can get from everyone. Things change, designs change, manufacturers have different ways of skinning cat, so I dont know if im missing something. Thats why we are all here right? To learn and help.

The cars newish to us, bought it to replace the wifes car a month or 2 ago, so this will be the first service by me. It looks like it has been serviced semi regularly by the service book, and looking at the oil colour and other items it looks like it has been cared for. That said i dont know when the last time the cap was taken off, i am pretty sure it is OEM (probably still original) going from memory. The plan was to change the coolant while i am at it so i know all the fluids and filters are new going forward. I will keep an eye out for the tabs when i go to look at it next, like i said its the wifes car so i dont see it that often to check. Will let you knw when i do 

@ Pnut. Ok, thanks for the additional info especially about service history and that you have never taken the cap off.

If you find it's not a mechanical alignment problem and look elsewhere it would be unusual for either one or both radiator cap seals (upper and lower, see photo below) to deform/degrade to the extent to cause your problem.  But, it's not impossible given that the radiator cap could possibly be 10 years old.

Maybe a judicious, medium tap with a rubber mallet on top of the radiator cap (when fully closed and then when at the first stop) could help free up anything that was sticking.

Also, turning the cap to the first stop, twisting up the cap as much as you can, and spraying lotsa water in there may help lubricate/free up something (it can't hurt). 

If it is a mechanical alignment issue, Force is your friend...until something breaks!

Please let us know your results .
 

[eye30]

Is possible that once you have twisted the cap and it is loose you then push down on the cap so the tabs clear each other then twist slightly more so the tabs on the cap lines up with the cut out and it pulls up.

[Pnut]

Thanks guys, i got it off in the end, just supported the radiator neck that it is on and pushed harder. That neck the caps on hangs out quite far and flexs a lot, I am surprised i haven't read of them snapping off when people try to remove the cap.

[TerryT]

Thanks guys, i got it off in the end, just supported the radiator neck that it is on and pushed harder. That neck the caps on hangs out quite far and flexs a lot, I am surprised i haven't read of them snapping off when people try to remove the cap.

@ Pnut.  Good to hear it's all sorted.