How to remove these bolt caps?

[Leftfootwonder]

Probably a silly question, but I am stumped. I've tried to lightly hammer and chisel and put a flathead screwdriver under to twist but they won't come off. There are hex bolts beneath them so they are supposed to come off. Trying to keep damage to a minimum.

Thank you.

[DonkeyApple]

Assuming they're plastic, if you eventually lose patience, then a wood drill bit (the type with the extra point) that's larger than the hex will make a neat hole to reveal the hex.

[JoshSm]

Depends on the detail but I'd think about using something like a thin scraper or palette knife or similar (maybe a couple of them) under the edge, and maybe soften them slightly with a hair dryer.

For levering you usually want something thin to get in the gap, and wide so it levers rather than the material failing under pressure. Might need working from different points as it probably won't pop straight off.

[P2KKA]

Are you sure they are caps?

[DonkeyApple]

I recently came across metal caps that screwed into the washer. If those caps are metal then possibly worth twisting them.

[Leftfootwonder]

Thanks all.

I should have said they are metal. I have tried twisting them with pliers too but to no avail.

Definitely caps as there are others which are already off which has exposed the bolt.

[JoshSm]

If they're press fit and if they've since had some moisture it could be tricky. Doesn't look like they were really intended to be removed.

Bit of heat still feels like it wouldn't hurt though.

[DonkeyApple]

Just be careful with the choice of tool you resort to after using the sensible ones you've already mentioned. Shattering Stanley blades pinging at one's eyes isn't fun.

As Josh suggests, a bit of hair dryer heat can't be a bad idea but if you're already missing a couple then destroying them using mole grips to twist them off isn't the end of the world. And then find some black rubber caps or similar to replace them all if desired?

[Richard-D]

Look like rivets to me.

[Belle427]

If they do come off start by tapping the head with a hammer to break the rust bond and then try to get some screwdrivers down behind to act as wedges to prise off.
Heat certainly would help if there isnt any rubber or plastic to damage.

[normalbloke]

Richard-D said:

Look like rivets to me.

That’s my thinking too.

[hengti]

Can you see the other end of the fastener by looking down the runner/box section? Is it threaded?

[fooman]

Leftfootwonder said:

Thanks all.

I should have said they are metal. I have tried twisting them with pliers too but to no avail.

Definitely caps as there are others which are already off which has exposed the bolt.

Are we looking at new seat rails next to old seat rails? They may have changed design and they are no longer caps but pressed - though if they are plastic you clearly don't need them, smash them off with a chisel!

[frisbee]

Are they secondhand? Someone may have replaced the ones that are bolted.

[netherfield]

Angle grinder to take the top off, then you can turn what's below, you can always glue some nut covers back on if needed, or replace bolts with hex heads and fit caps that way.

[Leftfootwonder]

frisbee said:

Are they secondhand? Someone may have replaced the ones that are bolted.

They are secondhand but I believe they are as they would be from OEM.

fooman said:

Are we looking at new seat rails next to old seat rails? They may have changed design and they are no longer caps but pressed - though if they are plastic you clearly don't need them, smash them off with a chisel!

No all the same, drivers and passengers. They are made of metal which is why they are such to get off!

Thanks for all your suggestions. I shall try some heat and go from there. Today ended up a hectic one so it's now a job for next weekend.