How to get rusted-up bolts/screws free with restricted access - help! Options

[Phoenix1971]

Hi allAm trying to fit a replacement bottom-entry flush valve in my toilet cistern - that's not the issue.What IS the issue is that it's a close-coupled one (didn't even know what that meant before today!) and I have to get the cistern separated from the toilet bowl so i can unscrew the old valve assembly and replace it before reattaching the cistern to the bowl. Here's the problem: the cistern is attached to the bowl by the 2 bolts/screws you can see circled red in the photo BUT they are rusted solid plus the access, as you can see from the pics, is extremely limited. I have pulled away the rubber washers that were there originally, plus chewed away at the screw heads as best I can with pliers / claw hammer etc but the lack of access, plus the fear of cracking the ceramic cistern/bowl, means I'm currently stuffed. What to do?HELP! Mark

Can't see the photo.

Have you tried wd40?

I cant see a pic either, but was also going suggest WD40.

All - thanks for responses. News to me the images hadn't uploaded!

WD 40 fan here too. Worked a treat on some rusty bolts on a garden swing structure. Spray a little for a few days to let it soak in then try the bolts.

Box wrench, looks like 10mm but check with spanner before buying.

Dremel with a flexy attachment on , grind the head of the screw off and they will just tap down/ through. 👍

few options I would try:

1. really liberal spray of wd40 and then box spanner as per above link. Issue with this is you might be able to get the box on but not the handle to give you any real leverage.

2. blowtorch to heat the nut and cause it to expand. Need to go careful as you might damage the porcelain, but if you need to replace these nuts otherwise the thing is useless anyway then why not.

3. drill out the bolt with a metal drill - then you should be able to rip the nut off. Again, depends on access space.

4. dremel the nut to slice it in two and then rip off. Again will depend on what space you have to get a dremel down there.

Sometimes it takes a few goes with wd40

Other thought is you might be able to get a hacksaw blade inbetween the bowl and cistern. Don’t put it in the full handle, just use the blade. Its gonna take a while but should do the trick unless the thing is really clamped down tight.

Why does everyone recommend WD40?

Yes it works as a lubricant but so does saliva.

A penetrating oil is much better..

Plusgas with the long thin tube for access to difficult areas. It freed up something that was very stubborn & resisted all methods.

Hi again all

Thank you SO much for rallying around as you did. This was one of those situations that unfolded and, at the end, you say to yourself 'if I'd known xyz at the outset then I'd have called someone to do it'. 10-12 hours all told across the weekend with skinned knuckles, cut fingers, broken drill bits and enough swearing to turn the air blue.

I eventually went with the drilling-out solution involving a 2mm pilot hole followed by a 6mm. One worked reasonably ok but the other went badly off-centre and i had to resort at the end to snapping the remainder of the screw-head away with pliers and a mole-wrench, luckily enough of it having been drilled away by that time.

And then on Saturday evening, just at the 11th hour when I thought it was sorted, I found out the hard way it wasn't. Silly me thinking 'no need to put any of that silicone stuff in like the previous people did - surely the rubber washers that came with the replacement valve assembly will be watertight, won't they?'

WRONG!

So I had to get silicone then go back there on Sunday to partially dismantle the toilet and put some silicone in to seal it properly. This should have taken 30 mins-1hr at most. But guess what? While unscrewing one of the 2 coupling bolts, the wing nut fell off and vanished into the space under the toilet bowl and trying to retrieve it took me another 2-3 hrs.

Last issue - the fill valve is a Fluidmaster bottom entry one with a brass shank, attached by a brass bolt to a braided flexible hose running up into it from the isolator. As you can imagine, access to it is extremely tight - pretty much like this and so I couldn't get a spanner or mole-wrench in there, only do the brass bolt up finger-tight and hope that the washer in the bolt stops it leaking. Which it seems to have done so far but I'm not happy about it. But - with the flexible hose running up into it, I can't get a box-spanner in there either.

Any suggestions?

But it must be great sitting on the throne and thinking yeah, I did this! For your next issue it’s hard to picture what you mean. Got a photo? Pipes seal at pretty low torques so it’s maybe not a huge issue. You can’t get any tool down there at all? Might need to install the pan hardware first and then connect into water pipe if that has more access? If you have an isolator valve there already then easy to do - just turn it a quarter turn to close and then disconnect. Reconnection put some ptfe or plumbers putty around the thread to seal.

Check YT or more silicon or a new loo! ;) Sorry I laughed at the bit where you lost the wingnut. :(
I replaced our flush for a concealed cistern, in the end that was easier than I thought but I did watch lots of videos first and buy a flush valve that didn't work. :)