radius arms and subframes (again)
Discussion
Well a days holiday. It's sunny and I am in the dark old garage.
Help please, should I be able to turn the pivot pin within the radius arm by hand on the bearings or should they be TIGHT?.
Second, is there any reason why i cannot put the rear sub frame in "empty" then refit the arms trumpets, cones etc afterwards?
Thanks for your help.
Help please, should I be able to turn the pivot pin within the radius arm by hand on the bearings or should they be TIGHT?.
Second, is there any reason why i cannot put the rear sub frame in "empty" then refit the arms trumpets, cones etc afterwards?
Thanks for your help.
Hi Sagalout,
If you've just renewed the radius arm pins and bushes, then the pin should be a firm but free fit in the bearings. It's the reamed bush which may make it seem a bit 'tight'. If it's reamed out to 13/16" it should all fit fine. If you are talking about an old pin in old bearings then they will be a bit worn and should turn more easily. You just have to use your judgement here, but the pin should definately not be too tight to turn fairly easily, perhaps with a pair of decent pliars.
You can fit the sub-frame bare if you wish, although it is a bit easier if you build up the basics off the car. I normally build up the brake pipes, the radius arms and the handbrake cables onto the frame first. The handbrake cables can be a real b****r if you don't feed them through the sub-frame first. Then put the unit into the car. That way it's not too heavy. Then add the rubber cones and trumpets, taking care not to get dirt or grit into the knuckle seat on the arm. Remember also to fit the dampers to the arms before trying to poke the damper tops into their seatings. Lastly connect up the handbrake cables.
At the front mountings where the bolts go in make sure you put lots of copper grease onto the threads and bracket faces to keep corrosion at bay. Check the threads first to make sure they are clean and the bolts 'run in' nicely.
Another tip - if you still have the petrol tank in the car you don't need to remove it to get at the top damper mounts. Just cut (very carefully) a 4.5" x 3" rectangular hole in the rear seat panel for access to the damper top nuts and cover it with an aluminium plate rivetted or PK screwed on with bath sealant afterwards. It makes access very easy in the future as well.
I hope all this helps. I'm going out in the sunshine now!
If you've just renewed the radius arm pins and bushes, then the pin should be a firm but free fit in the bearings. It's the reamed bush which may make it seem a bit 'tight'. If it's reamed out to 13/16" it should all fit fine. If you are talking about an old pin in old bearings then they will be a bit worn and should turn more easily. You just have to use your judgement here, but the pin should definately not be too tight to turn fairly easily, perhaps with a pair of decent pliars.
You can fit the sub-frame bare if you wish, although it is a bit easier if you build up the basics off the car. I normally build up the brake pipes, the radius arms and the handbrake cables onto the frame first. The handbrake cables can be a real b****r if you don't feed them through the sub-frame first. Then put the unit into the car. That way it's not too heavy. Then add the rubber cones and trumpets, taking care not to get dirt or grit into the knuckle seat on the arm. Remember also to fit the dampers to the arms before trying to poke the damper tops into their seatings. Lastly connect up the handbrake cables.
At the front mountings where the bolts go in make sure you put lots of copper grease onto the threads and bracket faces to keep corrosion at bay. Check the threads first to make sure they are clean and the bolts 'run in' nicely.
Another tip - if you still have the petrol tank in the car you don't need to remove it to get at the top damper mounts. Just cut (very carefully) a 4.5" x 3" rectangular hole in the rear seat panel for access to the damper top nuts and cover it with an aluminium plate rivetted or PK screwed on with bath sealant afterwards. It makes access very easy in the future as well.
I hope all this helps. I'm going out in the sunshine now!
Thanks, these are the existing pins in the arms. They won't turn even with 2 nuts locked together on the end!
I have started to DRIFT them out but whilst they are moving, they're not exactly sliding out. Worried about damaging the threads with the drift now.
Strange thing is, the bearing surfaces are lubricated and the arms moved up and down in the subframe. Now I suppose that could be pivoting on the ends but wouldn't have thought so.
The sub frame was replaced with an after market one many years ago, it seems in good condition but a lot of surface rust. Thought about Hammerrite but think I'll use this black body sealer containing Waxoyl it might stay on the sub frame longer.
Checked the alignment with the frame off the car but on level ground and with the wheels back on.
1 wheel vertical, t'other neg camber by about 5mm.
Tracking 1/8 toe in. Thats before I start. Now assuming the sub frame goes back in square,it shouldn't be tooooo bad.....
I have started to DRIFT them out but whilst they are moving, they're not exactly sliding out. Worried about damaging the threads with the drift now.
Strange thing is, the bearing surfaces are lubricated and the arms moved up and down in the subframe. Now I suppose that could be pivoting on the ends but wouldn't have thought so.
The sub frame was replaced with an after market one many years ago, it seems in good condition but a lot of surface rust. Thought about Hammerrite but think I'll use this black body sealer containing Waxoyl it might stay on the sub frame longer.
Checked the alignment with the frame off the car but on level ground and with the wheels back on.
1 wheel vertical, t'other neg camber by about 5mm.
Tracking 1/8 toe in. Thats before I start. Now assuming the sub frame goes back in square,it shouldn't be tooooo bad.....
The leverage of the arms from wheel centre line to pin centre line is quite high. It sounds as though you would be better off fitting new pins and bearings/bushes. All you need is a long 13/16" reamer.
If I were you I would set the camber on both sides to a little bit of negative. The 1/8" toe in is exactly correct.
If I were you I would set the camber on both sides to a little bit of negative. The 1/8" toe in is exactly correct.
I have decided to knock them out, for better or worse and have a look. the bearing surfaces look fine from whats knocked out so far, perhaps the new bushes haven't been reamed out properly when the last sub frame was fitted.
Reamer, (hmmm) had a couple of adjustable reamers for MGB king pins in 1978. I wonder where they went to....
Quiz question. Why is there a solid bush at one end but needle rollers at the other??
Reamer, (hmmm) had a couple of adjustable reamers for MGB king pins in 1978. I wonder where they went to....
Quiz question. Why is there a solid bush at one end but needle rollers at the other??
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