[richardbradford]

Hi, on-going topic, the long rear suspension bolts.

One bolt I couldn't remove so removed the rear hub with strut and an arm attached. Angle ground the arm off, pausing to check heat transfer levels. The angle ground the strut off and the removed remaing exposed segements of the bolt. Despite all this, those segments are still stuck fast.

My debate now is whether to drill or press these segments out. Press wise, am considering loading up from the outside, on both segments at the same time and pressing inwards, using short M8 bolts to press on the segments rather than the hub. Any change the hub will bend though? What ever the inter-metallic reaction between bolt and hub, these things seem effectively welded together.

Drilling is not going to be easy as these are high-grade hardened steel. Cobalt drill bit or should HSS be enough?

My car has been on 3 wheels for several days now so would be good to get this sorted, somehow...

Thanks in advance.

 

[horsewidower]

I would probably try Oxy/acetylene torch and heat it to cherry red a couple of times. If you don't have that, but have a welder, weld a couple of blobs on the ends of the bolts, that will heat the assembly also. This definitely looks like a job for heat.

 

[richardbradford]

Thanks. Reluctant to put in that much heat if can avoid it as will ruin the hub bush. Might come to it though... Angle grinding would have put quite a bit of heat in.
The section to camera did move in a bit when hammering inwards, though now flush with hub.

 

[Del]

"Press wise, am considering loading up from the outside, on both segments at the same time and pressing inwards, using short M8 bolts to press on the segments rather than the hub. Any change the hub will bend though?"

If you do that, try to put a steel tube between the flanges, or bar on one side of the flange faces, either cut to fit, to help take the compression load developed between the flanges. Using a torch as suggested above, but keeping the heat less than red hot, can help, expanding the dia of the lug holes ever so slightly.

Otherwise, I would suggest finding a used hub, sans bolts. What you have is pretty corroded in general.

 

[richardbradford]

Thanks, Del.

 

[richardbradford]

Took 90 mins of slow drilling, starting with 2mm bit then progressing in steps to 8mm, with regular oil added and pauses to clean swathe, but finally one of the segments is out.

Need to angle grind a flat surface on the other before starting to drill it so can keep it concentric. Happy that am finally able to be completing this process. replacement bolts are going to be very well anti-sieze protected.