Freeing up a seized hinge.

[mgarym]

Hi
I have a plastic hinge with a metal hinge pin that is seized.
I have soaked it in diesel for a few days but it is still solid,
I have also tried punching the pin out but don't want to force it and
break the plastic.
Any advice appreciated.

Gary

 

[zzr1200]

Take the E clips off both ends of the pivot pin, then drill a block of alloy or steel to the diameter of the pin and push it out in a press or a vice.

There are very little other options, you can't use heat, possibly penetrating fluid but I doubt that will work being as it's been soaking in diesel for days.

If you do get the pin out replace it with a stainless steel one.....

A replacement hinge???

Good luck

 

[Melvyn Best]

As above but try soaking in hot water before trying to remove the pin? Chances are the pin has rusted causing it to expand

 

[Nomad]

As above.

You could also remove both E clips then grip one end of the pin in a vice or mole grips.
If one part of the hinge has movement concentrate on that piece and work it backward & forwards being careful not to snap it,
If you can get one piece moving freely it will make it easier to press the other side out.

 

[500e]

How about removing clips then holding pin in vice and truing to move plastic in a circular movement while pouring boiling water on it, gentle movement.
No vice no problem here
To late not fast enough

 

[bricol]

I think by the time you've wrestled the rough, over-sized, rusty pin out, it might have been worth buying a new one.

The pin hasn't seized in the plastic like it would in a steel hinge, so the diesel isn't going to have done much - its now a nice, rough, friction fit in the plastic bits.

 

[Onoff]

Get some citric acid powder. Mix 1 of powder to 4 of near boiling water. Immerse the hinge and walk away. Come back in 24 hours. Rinse under cold water and try the action.

If as is likely the pin has rusted and swollen, if you pull it out you might damage the plastic bore.

You can also try white vinegar or cola but it'll take longer.

Nothing lost etc.

 

[arther dailey]

grind a flat on end of pin, centre pop , drill out hinge pin in slow stages untill its thin enough to just come out .

 

[Onoff]

Is that a rear window hinge off of a Massey Ferguson?

If so I'd try acid as above before drilling. They are silly money to replace.

 

[mgarym]

Thanks for all the suggestions,it's a hinge for a side window on a fiat tractor,
there are 2 of them both seized , can't find replacements but now you say Onoff they look very similar to Massey hinges si might have to buy new ones if some of the above suggestions don't work.

 

[mgarym]

Good idea but sadly I don't have a printer.

 

[Screwdriver]

Citric is your best bet. I use it all the time for jobs exactly like this. You might have to leave it for a few days.

 

[Agroshield]

Citric is your best bet.

Maybe we need to add that he should clean all diesel and oil residue off the part first.

Clean it well in very hot water with added detergent (washing powder or dishwasher powder).

The citric won't cut through any oil.

---

A question more than a suggestion: would electrolysis work? I am thinking not as the rusty parts are not exposed.

 

[Screwdriver]

Maybe we need to add that he should clean all diesel and oil residue off the part first.

Clean it well in very hot water with added detergent (washing powder or dishwasher powder).

The citric won't cut through any oil.

---

A question more than a suggestion: would electrolysis work? I am thinking not as the rusty parts are not exposed.

Yes good point. Any soapy solution in this case because of the plastic. As you rightly infer, you'd have to be vey careful if you wanted to use a solvent which would be my usual go-to.

Electrolysis would work just as well but since the metal is so well encased and both methods, citric or electrolysis, need to reach the affected surfaces, time is another requirement. Much easier/safer to let the thing soak in a tub of citric for a few days rather than have an electrolysis bath sitting there for the same period.

It might work after 24 hours as has been suggested but will definitely work after a few days.

 

[Onoff]

Once done I'd look to commission a couple of new pins in stainless and fit them and new stainless e-clips/circlips.

 

[Dilkris]

Is that a rear window hinge off of a Massey Ferguson?

If so I'd try acid as above before drilling. They are silly money to replace.

I'm really impressed you could recognize that.

 

[RichardM]

RS used to sell nylon hinges many years ago, don't know if they still do, but they may have something suitable if other options fail.

 

[Onoff]

I've actually just done a similar thing where the pin had rusted and expanded so much it had split the plastic handle it was in. Luckily it meant the pin came out. Had the pin re-made in stainless and 3D printed a new handle. Pictures when I find them.

I'm really impressed you could recognize that.

BiL is a Massey fanatic. Then up the pub I'm the odd one out as I haven't got a tractor. They all go on runs. First question I was asked upon meeting an old regular (local farmer) for the first time up there "You got a tractor?"

 

[mgarym]

So where is the est place for getting citric acid .
We have a ASDA that sells Elbow Grease citric acid
would that be suitable?

 

[Screwdriver]

Get a bag of it off eBay.