Help - alu ring bonded to threaded shaft

[N2ae86]

Howdy chaps,

I am after some sage advice from someone that might know what they are doing ... as in not me!

Just bought a car for cheap trackday fun and hit a problem trying to wind the coil overs down. Basically the aluminium locking ring simply wont budge on the threaded shaft. Its locked solid and simply wont move. I think the threaded shaft is stainless

I dont know if its corroded, or some wally has used some sort of adhesive to locking the thing in place. Around the top of the ring is a whiteish substance - dunno if its glue or an aluminium reaction. Seems weird that there is corrosion mainly as the whole unit is looking pretty fresh!

I have tried hitting it around with a extension bar and mallet. I have tried heat. I have soaked it in WD40, nail varnish (heard this was good for disolving super glue) and thinners. I have boiled it for an age (also heard it was good for breaking super glue). More heat, more hitting more straining with C spanners, attached to very long bars.

I am buying a big vice on the weekend for a last ditch attempt but I was wondering if anyone had any clever suggestions on how I might be able to break the ring free from what ever has bonded it into place - any clever ways for breaking down alu corrosion etc?

Thanks for the help in advance - its p*****g me off so much I had to go out of the garage and bash something with my hammer until I had chilled off!

Cheers

James

 

[Pete.]

Get a heat gun on it. Aluminium expands vastly greater than steel (or stainless) with heat. Get the ring hot and it will loosen. Over 400 degrees and it will also release any possible threadlocking compound.

 

[piman]

Hello James,

coilovers normally have two rings, one locking the other in place, are you trying to slacken two as one?

Alec

 

[Airbrass]

Stainless & alluminium in contact together will corrode & is very difficult to shift.

If you suspect threadlock use heat to shift.

good luck

 

[hareng]

As above coilovers will need two C type spanners, lower one acting as a locking ring. Better off positioning the two C type spanners so you would close together like pliers one handed, one will undo surprisingly easier than two hands.

Usually threaded on steel, rings probably zinc plated ms or aluminium. They will corrode within 12 months leaving a white residue build up.
FK/Koni supply a spray when assembling.
Carefull with heat.
Could leave a solvent or penetrate like plusgas though never been any good on everything tried it on to date, i prefer LT8 just leave a few mins, if that dont cure it nothing will.

 

[N2ae86]

Hi Chaps,

Thanks for the responses - out of interest is it possible to burn off the anodised coating? Will attack it again with alot of heat, slap it in a vice and then try and wrench it off with a C spanner with a long pole attached.

Here is a snap of the locking ring and threaded section - thankfully it slips of the shock otherwise I would be properly boned for heating it up without the shocking blowing up.

Whilst I think it may also be corrosion it does seem odd as the other locking ring is in tidy condition and the threaded piece is also corrosion free.


Do you chaps happen to know how how hard aluminimum oxide corrosion is - is it easily scratched away with a screwdriver edge.

I am really worried the other 3 are this bad - bit of a pisser really, coil overs work perfectly too and are pretty dear even second hand!

Cheers guys!

 

[Shox Dr]

Sounds like Galvanic corrosion. (a pic might help)

Buy some Caustic soda either wrap a cloth around the preload collar, and soak in the solution, or put the whole damper in solution, But you must keep an eye on it as it will react very quickly, and if left will dissolve the whole ring.


edit OK, picture posted up since I started writing this, reply. Another reason maybe the locking nut wasn't backed up, and the threads have jumped, if this is the case you'll have a hell of a time trying to get them to move. If the Preload adjusters are available as a part I'd cut the old ones off and just buy some new ones

 

[brightspark]

what make are they . if there avo or spax u can get the locking rings as spares just cut the old ones off

 

[Pete.]

If you put those parts in a vice tight enough to use any meaningful force on them, I doubt you'll ever be able to use them again. Those things will crush very easily.

 

[chunkolini]

If it gets desperate try cutting it off using a slitting disc, make cuts on opposite sides, dont go in as far as the steel part and you should be able to get a screw driver in the cuts and wiggle it until it fatigues.

Chunko'.

 

[N2ae86]

Man this is a real p****r - I am hoping they will come loose once I have it in a vice and use some more leverage on it.

The shocks are Cusco and typically impossible to buy bits for - was thinking I would just bin off the threaded shaft and locking rings and buy those slip on collars you can get from Rallyparts etc - and get those welded onto the shock.

Thing is the shafts are around 2.5 ins dia and everything else is alot smaller.

If I go the caustic soda route will it attack the oxide corrosion first before it starts eating away at the rest of the locking ring?

 

[N2ae86]

If I cut the rings off - how dear would it be to get someone to fab me up some replacement rings in Alu / Steel? Guessing it would cost a bomb?

 

[PhillipM]

If you can measure the thread up for me I'll check see if I've got any spare, got loads of the bloody things, from 2.25's to 3" diameter, chances are there'll be some the right size but that looks like an acme/buttress thread?

If not I'd be tempted to just buy some adjuster rings, and have a steel sleeve machined up to match, should work out fairly cheap.

 

[N2ae86]

If you can measure the thread up for me I'll check see if I've got any spare, got loads of the bloody things, from 2.25's to 3" diameter, chances are there'll be some the right size but that looks like an acme/buttress thread?

If not I'd be tempted to just buy some adjuster rings, and have a steel sleeve machined up to match, should work out fairly cheap.

Hi Phil, I will have a measure and let you know – just in case you have any spares.

I am going to have another pop at it this weekend. I am going to try household bleech, vinegar, and if that doesn’t work a local platers had said he will dunk them in his cleaning solution which may help break the bond – then its vice, heat and a breaker bar. Something has to shift it!

In terms of getting a steel sleeve machined – what would that potentially cost. Get the feeling if I approach a local engineering works I will probably get raped financially.

Cheers

James

 

[PhillipM]

The local lads down here would probably charge about £20-30 for two sleeves done in the dinner hour...

If it's sized to take a 2.5 or 3" spring on the outside then Andy@Milners probably has some used Fox coilover rings you could buy, might even have some farked old bodies you can chop your threaded bit out of if your lucky.

If you measure up I'll see him this weekend and ask.

 

[Balders]

Don't use caustic soda on aluminium. It'll eat the crap out of it, could cause lots of heat & the bubbles given off are mainly hydrogen (google drano bomb ). Will certainly marr the ally - maybe to the point of FUBAR'd

Use acetic acid (proper vinegar - not non brewed condiment, most liquid kettle de-scalers or photographic stop bath), it will attack the ally oxide - not the ally

HTH