W211 rear swing arm removal impossible (spring type, not air).

[james2747]

I am trying to remove the steel swing arm to shot blast and repaint to prevent any further corrosion. It would not normally be a difficult job BUT!!
The bolt that secures the arm to the rear (inboard) bush (see photo) has apparently corroded to the central metal spacer that is moulded through the centre of the rubber bush. So after removing the nut and trying to turn the bolt (splined socket head) I can detect it simply trying to turn the rubber bush ... as the bolt and central metal tube of the rubber bush are now 'as one' due to corrosion, so I can't even get much torque on the bolt as I fear it will just break the bond between the central metal spacer and the rubber bush.
I am sure if I put a breaker bar on the bolt, it would turn 360 degrees but the result would be the central spacer tube would just tear away from the actual rubber bush, damaging the bush and still leaving me no nearer to getting the bolt out ... and the arm off! Heat is not possible, it would just destroy the rubber. Weeks of frequent application of spray penetrating fluid has made no difference. I don't want to butcher anything as I am sure replacing the bush in the subframe wont be too easy but I'm at a loss to any further ideas on how I can break the corroded bond between bolt and central metal bit of the bush, to allow me to extract the bolt. Any ideas most welcomed.

 

[Wighty]

I am trying to remove the steel swing arm to shot blast and repaint to prevent any further corrosion. It would not normally be a difficult job BUT!!
The bolt that secures the arm to the rear (inboard) bush (see photo) has apparently corroded to the central metal spacer that is moulded through the centre of the rubber bush. So after removing the nut and trying to turn the bolt (splined socket head) I can detect it simply trying to turn the rubber bush ... as the bolt and central metal tube of the rubber bush are now 'as one' due to corrosion, so I can't even get much torque on the bolt as I fear it will just break the bond between the central metal spacer and the rubber bush.
I am sure if I put a breaker bar on the bolt, it would turn 360 degrees but the result would be the central spacer tube would just tear away from the actual rubber bush, damaging the bush and still leaving me no nearer to getting the bolt out ... and the arm off! Heat is not possible, it would just destroy the rubber. Weeks of frequent application of spray penetrating fluid has made no difference. I don't want to butcher anything as I am sure replacing the bush in the subframe wont be too easy but I'm at a loss to any further ideas on how I can break the corroded bond between bolt and central metal bit of the bush, to allow me to extract the bolt. Any ideas most welcomed.

Mine were totally seized to the bolt and bush , after 20 hours of trying I limped it up to the garage a mile away , they cut it all off and out with a torch and air tools . Fitted a new bush and then my supplied arms (both sides) .
They took the exhaust off to gain better access , but that was my W211 which may duffer to your E class .

 

[brandwooddixon]

I think that you may need to remove the road spring before attempting to undo that bolt as it will be under significant side load as it is the leverage point for the control arm.
In any case the short answer is that whatever you try you run the risk of damaging the bush.
Penetrating oil will attack the rubber, and as you correctly surmise the rubber to bushing contact strength may be less than the bolt to bushing contact force.
You could try shocking the bolt along the linearly (hitting it) or heat and cool, but I would be prepared to replace the bush.

 

[Wighty]

I think that you may need to remove the road spring before attempting to undo that bolt as it will be under significant side load as it is the leverage point for the control arm.
In any case the short answer is that whatever you try you run the risk of damaging the bush.
Penetrating oil will attack the rubber, and as you correctly surmise the rubber to bushing contact strength may be less than the bolt to bushing contact force.
You could try shocking the bolt along the linearly (hitting it) or heat and cool, but I would be prepared to replace the bush.

I think he has used a tinternet picture , because both his hands are on spanners ?

 

[james2747]

I think he has used a tinternet picture , because both his hands are on spanners ?

Wighty, how could you be so persnickety?!
My F.1 mechanic was holding the spanners while my very expensive photographer did the artistic business.
As I am the boss in my garage, I never get my hands dirty and was the senior executive in charge of proceedings.
What's that .... is that a flying pig I see?? LOL!

 

[Wighty]

Wighty, how could you be so persnickety?!
My F.1 mechanic was holding the spanners while my very expensive photographer did the artistic business.
As I am the boss in my garage, I never get my hands dirty and was the senior executive in charge of proceedings.
What's that .... is that a flying pig I see?? LOL!

Funny buddy !
I thought you would have had bigger hands

 

[00slk]

Luckily my bolt came out.
If the OP has to cut off the lower arm, I have a N/S rear coil spring type here.