Had my car in for a service at Ford and they told me that the plastic radiator cap was stuck solid and un-able to remove it to check the antifreeze 

Dealership said the cap & tank will need to be re-newed! I thought to myself ''No way I'll change the cap myself''...So ordered a new cap and said I'll fit it myself.

Turns out the top of the cap has parted company with the lower section and looked like I'd wreck everything in getting the stuck part out, no release agents would shift it, so drilled the cap in a X shape until the part collapsed in on itself and then was able to carefully lever the cap out the tank.

Seems its a common fault with the Fiesta and other Fords as well  The two rubber sealing rings expand and jam against the inside of the white bottle and the only way to stop this from happening is to apply silicone grease to the rubber seals and inside the tank, Dealership advises to remove the cap every few months and re-apply the grease to stop it from jamming up again.

Have any of you guys checked your rad' caps lately ?? 

A bit late for me but this is what's needed to stop the cap from getting jammed.

 

 

Good tip. Modern cars do not get weekly checks as the older cars did.

I had same thing happen to mine cut mine out with red hot knife

i now check it every week

my other half had same problem on her fiesta 2 weeks ago. coolant was under minimum so went to top it up and top half come out bottom half stayed in. it only popped out after i had wrestled with it for half  an hour and then poured warm water on it. funny thing is when i went fords and asked for a new reservoir cap the feller said he knows what the part number of the bottle is without looking on computer as its another pretty common problem.

1 hour ago, Typhoonf2 said:

 funny thing is when i went fords and asked for a new reservoir cap the feller said he knows what the part number of the bottle is without looking on computer as its another pretty common problem.

That very day our local dealership had re-newed 6 new caps & 3 new tanks!! I reckon Ford should be doing something about this fault.

2 hours ago, karl46 said:

Good tip. Modern cars do not get weekly checks as the older cars did.

Most old cars had a reliable push & turn cap which was made out of metal.... Everything is made of plastic these days 

Thanks for the tip Ian.   Have never considered taking the cap off as the level is OK.

20 hours ago, Bobr said:

  Have never considered taking the cap off as the level is OK.

Same here Bob! For how long it takes to pop the bonnet and remove the cap I'll be doing this check & re-grease every 3 months.

I had this same problem . Took the car to my local garage and they removed the part that was stuck and replaced the cap for £10 . I've since bought a tin of silicone lubricant and will be using that on the cap every couple of months to stop it ceasing up again. 

Poor design by Ford 

not done this had to top it up about 2 months ago but put it back dry can i get some of this silicone lube from halfords as i have the discount card.

2 hours ago, AlexBartlam said:

not done this had to top it up about 2 months ago but put it back dry can i get some of this silicone lube from halfords as i have the discount card.

Depends on the Halfords you use, our one didn't have any so I popped into the maplins next door and bought a tube of silicon grease for just over £4 :)

just had the same thing happen to me temperature going 120 degrees cant get coolant in it to sort it because the caps goosed .took it to a garage who managed to get a little bit of open so i could actually get water in to it nightmare service booked at dealership hopefully they will sort it and if this is a known fault free of charge repair i hope 

Bet they charge if out of warranty.. 

On 1/22/2020 at 3:00 PM, david lundie said:

 service booked at dealership hopefully they will sort it and if this is a known fault free of charge repair i hope 

Buy a brand new cap from Ford or ebay and fit it yourself, it'll cost you £12 at the most, the rest of the broken cap wedged inside the tank can be steadily eased out with two small flat-head screwdrivers, working it upwards, until it is out, apply silicone grease to the two rubber seals on the new cap and apply the grease to the inside of the white tank.

As for the dealership they might want to change the tank & cap as one whole job and charge you even more labour charges.

On 2/26/2017 at 6:48 PM, Ian Lanc said:

Same here Bob! For how long it takes to pop the bonnet and remove the cap I'll be doing this check & re-grease every 3 months.

Thought I'd take the cap off this morning so I bought some silicone grease from Amazon (small tube was £3.49) and went to take it off.   Couldn't move it.   It was stuck solid.    So I borrowed a small pair of Stilsons and, fully expecting to have to get a new cap, started to undo it.   To my surprise, it came off in one piece.   It is now liberally coated in silicone grease and can be undone with ease.

6 hours ago, Bobr said:

  To my surprise, it came off in one piece.   It is now liberally coated in silicone grease and can be undone with ease.

Lucky bugger Bob.

Checked it again this morning and it came of easily by hand.

After reading this topic and knowing that I have never removed the rad cap from my2015 Fiesta,  I went out and checked - sure enough  I could turn the cap about 3/4 of a turn but could not pull it out. !!  
Still,  better to know now when I can sort it at my leisure.

A small pair of water pump pliers do the job of removing our mark 6 fiesta caps if they're tight. I then grease the seals, checked twice a month (coolant level is checked daily) 

41 minutes ago, Ian123 said:

After reading this topic and knowing that I have never removed the rad cap from my2015 Fiesta,  I went out and checked - sure enough  I could turn the cap about 3/4 of a turn but could not pull it out. !!  
Still,  better to know now when I can sort it at my leisure.

You have to unscrew it completely before you can pull it out.   I think mine turns about three complete turns.   I'll check in the morning.

14 hours ago, Ian123 said:

After reading this topic and knowing that I have never removed the rad cap from my2015 Fiesta,  I went out and checked - sure enough  I could turn the cap about 3/4 of a turn but could not pull it out. !!  
Still,  better to know now when I can sort it at my leisure.

Checked this morning and my rad cap turns 4 complete turns before I can pull it out Ian.   Even with the silicone grease on it's still a little stiff but it can be turned by hand.