Silentbloc bush stuck

[adriantr4]

Hello

I'm refreshing the rear suspension on my '4, and l have removed the leaf spring without too much trouble. However, the silentbloc bush on the front has remained stuck on the front bolt and disassembled itself. 

Any thoughts on how to remove it? cut off the remaining rubber and heat/mole grips? I've got an angle grinder but I'm not keen on this approach.

Access isn't great, but the rear wing is off.

Thanks, Adrian 

 

 

[BlueTR3A-5EKT]

33 minutes ago, adriantr4 said:

Hello

I'm refreshing the rear suspension on my '4, and l have removed the leaf spring without too much trouble. However, the silentbloc bush on the front has remained stuck on the front bolt and disassembled itself. 

Any thoughts on how to remove it? cut off the remaining rubber and heat/mole grips? I've got an angle grinder but I'm not keen on this approach.

Access isn't great, but the rear wing is off.

Thanks, Adrian 

 

 

Yes carefully cut grind the offending bit off.    Be careful not to damage the chassis pin or you will open a serious can of worms.   if you need to remove it from the chassis and renew it, it will be seized and lifting the body high enough so you can slug at it with a hammer will test your humour.   We early car owners cannot remove the rear leaf spring without removing the pin from the chassis.   
 

New bushes are available.  107769.   https://www.moss-europe.co.uk/bush-spring-eye-rear-spring-107769.html
 

Edited February 19 by BlueTR3A-5EKT

[John Morrison]

Hi Adrian how you doing?

re this bush I’d get every bit of rubber off, hacksaw Stanley knife and finish with 40 grit sandpaper 

when all you have is shiny then I would try heat on the remaing tube

try warming it up and then tapping it along the pin with a hammer and chisel if you get movement then moles could work but having them tight enough tends to squash the tube onto the pin

angle grinder is the last resort cause you can easily damage the pin 

 

John

 

[Motorsport Mickey]

Adrian,

The guys are right, you have to try and not damage the pin underneath.

However an ace "get out" I've applied to the front pins on the chassis (which you can use on the rears leaf spring pins, is after you have removed all the rubber down to a steel tube over the pin, attack it with a 2" cutter disc in a Dremel or somesuch small controllable hand grinder. Cut the bush length ways starting from the end where you can see how far through you can cut without damaging the pin surface, and then proceed down the length of the pin estimating the cutting depth. When you get near the chassis and you can't get the cutting disc into the corner... stop, and attack the 3/4 cut through tube with a Stillson (monkey wrench) or other self-tightening wrench, which tightens onto the tube surface when you apply force. If it still won't come off, (unusual), warm the tube up quickly with an oxy torch or even a plumber's torch and again attack the bush with the same tools. The tightening action with the dragging teeth biting into the bush, tries to peel the tube apart down the cut length opening it up away from corrosion which is probably sticking it.

Don't worry about marking or cutting the pin surface, because the cut is down the length of the pin dia, rather than across it, if you go a little too deep (probably 10 thou or less) the surface will only have a very narrow slit cut into it, and because it's not across the axis of the pin, it doesn't start a shear point for failure. I just fill the slit with Araldite or other (J B Weld ?) 2 pack adhesive and smooth it flush with the radial surface ...and job done. 

Mick Richards

Edited February 19 by Motorsport Mickey

[adriantr4]

Hello

Thanks for suggestions.

I have to report that both I and the bush are equally stuck. I've cut in and along as deep and and as far as I can, and heated with a plumbers torch. I have also attempted to hit with a chisel and twist it to open the split, but no go. It's like it's fused to the pin.

I am rather out of ideas now: weld a bar across it, heat to red-hot and ...?

There is no room for a puller.

Any ideas?

Thanks Adrian 

[stuart]

35 minutes ago, adriantr4 said:

Hello

Thanks for suggestions.

I have to report that both I and the bush are equally stuck. I've cut in and along as deep and and as far as I can, and heated with a plumbers torch. I have also attempted to hit with a chisel and twist it to open the split, but no go. It's like it's fused to the pin.

I am rather out of ideas now: weld a bar across it, heat to red-hot and ...?

There is no room for a puller.

Any ideas?

Thanks Adrian 

TBH it doesnt look as if youve gone in far enough with the split, do you have a good sharp small chisel to go the last bit then add some heat.

Stuart.

[BlueTR3A-5EKT]

I have had success on the lower inner front steel bushes, which are hardened and rusted solid, with one of these nut splitters.   Now you have a groove cut the blade of the splitter can be set in it and tightened at different positions along the rusted tube’s length.  Try tighten then rotating the tool/bush to free the rusted bit from the chassis pin.

 

 https://www.toolstation.com/nut-splitter-set/p80007

Edited February 22 by BlueTR3A-5EKT
spelling correction to an approved post has caused it to be re hidden

[adriantr4]

Thanks to everyone. I have invested in a propane torch, chisels, Dremel diamond cutters and nut splitter set (an excellent idea).

All this won't arrive until next week. In the meantime all other suggestions welcome.

Regards Adrian 

[BlueTR3A-5EKT]

Have you tried to grip and rotate it as suggested using mole/vise grips?  Curved face jaw type might be better than flat faced.

[adriantr4]

Hi - yes I have curved mole grips. Thanks for the suggestion. I think serious heat is going to be key to the solution. I hope....

Regards Adrian 

[Motorsport Mickey]

Adrian, the Mole grips are a poor second as against a Stillson (Monkey wrench). Even with a curved jaw the Mole grips work by opposing force transferring to each jaw...it pinches it together, that means the bush will be trapped against the pin surface inside it. 

The Stillson works by the backward angled teeth being pressed together by the application of force to the handle, but this is the bit that makes it work. On the photos below the rubber bush has a split line marked in white, you open and position the Stillson moving jaw leaning backwards (that's why there is a rivet pin to allow it to swivel) so the top jaw of the Stillson is positioned slightly above the bush split line directly opposite it,

 

then the lower fixed jaw on top of the handle is positioned to lever against the split bush on the bottom half at the split line, so it engages with the split edge in the bush, then push down on the handle the Stillson rotates and the  jaw angles into the centre and picks up the split edge and imparts a twisting action to the bush surface. Check out the photos where I've marked a rubber bush white where the split line would be and how the jaw moves in now running parallel to the handle jaw to pick up the split edge on its rear couple of teeth.

 

Personally I would use your best anti seize spray and jet it into the split area and down to the root of the stud where you can't currently get down to with the chisel or cutting discs, the above method works for me.

Mick Richards

Edited February 24 by Motorsport Mickey

[adriantr4]

Hello - success! My new propane torch did the trick. I seriously heated the bush up, tried a few hard taps with my new chisels - nothing. Tried the mole grips as a last resort and it just gave in, easy after that.

Thanks to all Posters, advice much appreciated.

I think the order of attack should be: massive heat, if that fails then a lengthwise partial slot with a Dremel (I used a thin angle grinder disc, which regret - I later used a Dremel disc in a drill which worked fine), then Stillson as described,plus Heat. I also used PlusGas spray.

In the past my last resort has always been Heat. The expansion/contraction forces must be colossal, and localised. 

Now for the refurb - then the other side!

Adrian 

 

 

[John Morrison]

Way you go Adrian, another reason to be chuffed!

John.

[BlueTR3A-5EKT]

I am now awaiting season 2.. Silentbloc Revisited