Jumper 2010 coolant cap stuck

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mummo
Posts: 2
Joined: 04 Oct 2026, 14:10

Jumper 2010 coolant cap stuck

Unread post by mummo »

Hey,

This 2010 Jumper had something weird happening with coolant level, and pressure remaining even when engine was cold. So we changed the coolant reservoir cap (no signs of head gasket issues).

Put the new cap on, drove the car, let it stand overnight and today when I tried to open the coolant cap its properly stuck. There are claws in the cap that fit a claw in the reservoir itself. The new cap is identical to the old one, but this never happened with the previous cap. Now it simply cannot be opened without breaking the claw. I tried googling what the mechanism with the claws is but nothing came up. Can someone wiser give some insight?
cap.png
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Sloppysod
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Re: Jumper 2010 coolant cap stuck

Unread post by Sloppysod »

Treat it like a medicine/tablet cap, try squeezing it 90° to the 'claws', that will make them move outwards, thus allowing to turn the cap.
Stu 🏴󠁧󠁢󠁷󠁬󠁳󠁿

"Some cause happiness wherever they go, others whenever they go"Oscar Wilde (1854-1900)
mummo
Posts: 2
Joined: 04 Oct 2026, 14:10

Re: Jumper 2010 coolant cap stuck

Unread post by mummo »

Sloppysod wrote: 04 Oct 2026, 14:28 Treat it like a medicine/tablet cap, try squeezing it 90° to the 'claws', that will make them move outwards, thus allowing to turn the cap.
Hey,

Is that how it's supposed to work? Cause I tried that and it didnt work. The cap is pretty thick and tough to squeeze.
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Sloppysod
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Re: Jumper 2010 coolant cap stuck

Unread post by Sloppysod »

mummo wrote: 04 Oct 2026, 14:31 Hey,
Is that how it's supposed to work? Cause I tried that and it didnt work. The cap is pretty thick and tough to squeeze.
It's supposed to he difficult, so you can't accidentally remove the cap.
Stu 🏴󠁧󠁢󠁷󠁬󠁳󠁿

"Some cause happiness wherever they go, others whenever they go"Oscar Wilde (1854-1900)