Getting A Large Plastic Nut Undone

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pollys1dad
Posts: 208
Joined: Mon Jun 25, 2012 12:13 pm
Location: Wiltshire United Kingdom

Getting A Large Plastic Nut Undone

Post by pollys1dad » Fri Feb 28, 2020 4:49 pm

This pinch valve, have had both end caps off recently. Had to remove them again, as the pinch valve sleeve itself failed. I got the back one undone easily enough but the front one won't budge, see white arrow.I have tried various approaches but no joy. The valve body is made from polypropylene or nylon.
Anyone got any ideas?
Cheers
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Russ Hanscom
Posts: 1635
Joined: Wed Mar 15, 2006 11:10 pm
Location: Farmington, NM

Re: Getting A Large Plastic Nut Undone

Post by Russ Hanscom » Fri Feb 28, 2020 6:07 pm

I like channel lock pliers, or water pump piers, or a chain strap wrench - all will work, but will scar the nuts a bit.. Looks like you have already tried the "right" tools.

pollys1dad
Posts: 208
Joined: Mon Jun 25, 2012 12:13 pm
Location: Wiltshire United Kingdom

Re: Getting A Large Plastic Nut Undone

Post by pollys1dad » Sat Feb 29, 2020 3:59 am

" chain strap wrench " Ah, thanks for the suggestion, a chain strap would likely mar the plastic nut. That said I see their are soft grip strap wrenches that have a rubber strap. I think I'll be getting one of those, just reading the Amazon reviews. Will get back to the forum, saying how I got on.
Thanks for pointing me in the right direction:)

Harold_V
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Re: Getting A Large Plastic Nut Undone

Post by Harold_V » Sat Feb 29, 2020 5:07 pm

pollys1dad wrote:
Fri Feb 28, 2020 4:49 pm
I got the back one undone easily enough but the front one won't budge, see white arrow.I have tried various approaches but no joy. The valve body is made from polypropylene or nylon.
Hmmm. I'm inclined to think that the plastic has galled, which may result in a destroyed valve. Once that happens, any movement just exacerbates the condition.

It's going to be interesting reading how this shakes out.

H
Wise people talk because they have something to say. Fools talk because they have to say something.

pollys1dad
Posts: 208
Joined: Mon Jun 25, 2012 12:13 pm
Location: Wiltshire United Kingdom

Re: Getting A Large Plastic Nut Undone

Post by pollys1dad » Sat Feb 29, 2020 5:29 pm

I've ordered two of the soft grip straps, claim will grip on any shape. So will put one around the nut and the other at the far end of the barrel. Will let the forum know how I get on. Attached couple of photos of damage to the sleeve, can only see part of it. I can also see what I think is quite a long slit in the wall, when not receiving pressure will be in normal shape, as made from a hard material, any tear would only be visable when pinched, grit was coming out, from the actuation port on the pinch valve, then coming out of the pressure on/off foot pedal.
Cheers.
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pollys1dad
Posts: 208
Joined: Mon Jun 25, 2012 12:13 pm
Location: Wiltshire United Kingdom

Re: Getting A Large Plastic Nut Undone

Post by pollys1dad » Sun Mar 01, 2020 6:20 pm

Harold_V wrote:
Sat Feb 29, 2020 5:07 pm
pollys1dad wrote:
Fri Feb 28, 2020 4:49 pm
I got the back one undone easily enough but the front one won't budge, see white arrow.I have tried various approaches but no joy. The valve body is made from polypropylene or nylon.
Hmmm. I'm inclined to think that the plastic has galled, which may result in a destroyed valve. Once that happens, any movement just exacerbates the condition.

It's going to be interesting reading how this shakes out.

H
The two straps were delivered by Amazon Prime at 18:25. Photo A, one strap nice an tight on barrel of pinch valve housing and trying to fit other on nut of end cap but strap is too wide, slips off when tried to torque it, photo C, if they do a narrower version probaly work fine. I used the original tool I used to tighten and undo end caps. As other strap was such a good grip on the barrel, undid the end cap with silver tool, ( much narrower jaws ) very easily.
When get the pinch valve sleeve out, might be of interest to see the damage, so will post a pic or two.
As got end end cap off and can get at sleeve....Happy Bunny :)
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