Sprint sub-frame torque and steering column bush washers
Posted: Wed Oct 07, 2015 5:17 am
Hi.
I'm hoping someone can provide some help with a couple of issues. Thanks in advance.
I have a 1980 Sprint that got exported to it's current home in Perth Western Australia. It doesn't get driven a lot truth be told and for the last "a long time" it has been pending getting a few things fixed. Firstly it was the rear axle seals but that has then turned into a realisation that a few suspension bushes need replacing.
I have two current issues.
Firstly regarding the rear sub-frame bushes. It had poly ones during a rebuild but one had split so they are being replaced. It's the NS one that split and I started on that side. The bolt came undone OK revealing everything is basically sound - a bit of surface rust on the chassis leg under the washer bush and the conical washer is a bit tired. At this point I've zinc galv painted it and re-used it but might replace it. It's just tedious ordering stuff from the UK in the middle of the job.
Here's the thing though. The WM states a torque of 48lbft. I started tightening and got to maybe 30 when the washer bush was looking very compressed and splayed. I figured it would split and backed off. The sub frame is on axle stands so its all sitting there mid-job. Also I'm using superflex ploy bushes for the new parts.
I realise the front sub-frame bushes have a spacer tube but there is no such part on the rear ones so I can't see how the suspension bush would ever withstand 48lbft. As far as my car is concerned the connection part sequence starting in the engine bay is : bolt, large steel washer .... bolt through chassis leg (in tube as I understand it)... flat washer bush, sub frame, shaped lower suspension bush, conical washer, nut.
I've asked superflex for an opinion about this. Also the person who rebuilt the car 12 or so years ago. There are two different opinions.
One is the chassis leg has a protruding tube (extension of the tube within the chassis leg?) that passes through the washer bush and abuts the top of the conical washer, thereby you'd assume, enabling the whole thing to be tightened up to 48lbft in just the right way that its all tight and the suspension bushes are acting as a clamp but not compressed to destruction. The other opinion is that there is no protruding tube at all and the washer bush simply sits between the chassis leg and sub-frame with the whole thing appropriately tightened - 48lbft being too much.
So which is correct? There is no protruding tube on my car nor any sign there ever was. When I finally get to the OS one - totally inaccessible due to steering linkage - I will compare of course. I can't help thinking that if there was a protruding tube it would have to be exactly the right length otherwise it would either do nothing (merely acting as a locating spigot for the washer bush if it were too short) or would cause insufficient clamping of the arrangement if too long ie causing a bolted join between the metal parts and rendering the bushes useless). It just seems a stretch to imagine the mechanism would depend on this and that it would be reliable.
If it turns out a protruding tube is supposed to be there I have some awkward issues. I'm not sure how that would be accurately fixed and not in a rush to visit a welding shop anyway. Could washers be used ? But then of course there's the issue of what depth of washers would be required. If there is a protruding tube can anyone advise how much it protrudes?
Second question is much shorter. I'm also replacing the bush where the steering column goes through the bulkhead. Probably impossible to remove the column due to wiring bulk and so the parcel shelf will have to come out too. But the column is clear of the hole so I think I can work this without full column removal. The WM talks about two washers around the bulkhead bush - a steel one on the engine side and a plastic one on the inside. I assume to limit wear on the bush? I have the steel one but the plastic one is not there. Does anybody know where I could get the plastic one or, if I made something myself, how thick it needs to be and what material could be used to make it? (and what is the original made of? )
Thank you
Mark
I'm hoping someone can provide some help with a couple of issues. Thanks in advance.
I have a 1980 Sprint that got exported to it's current home in Perth Western Australia. It doesn't get driven a lot truth be told and for the last "a long time" it has been pending getting a few things fixed. Firstly it was the rear axle seals but that has then turned into a realisation that a few suspension bushes need replacing.
I have two current issues.
Firstly regarding the rear sub-frame bushes. It had poly ones during a rebuild but one had split so they are being replaced. It's the NS one that split and I started on that side. The bolt came undone OK revealing everything is basically sound - a bit of surface rust on the chassis leg under the washer bush and the conical washer is a bit tired. At this point I've zinc galv painted it and re-used it but might replace it. It's just tedious ordering stuff from the UK in the middle of the job.
Here's the thing though. The WM states a torque of 48lbft. I started tightening and got to maybe 30 when the washer bush was looking very compressed and splayed. I figured it would split and backed off. The sub frame is on axle stands so its all sitting there mid-job. Also I'm using superflex ploy bushes for the new parts.
I realise the front sub-frame bushes have a spacer tube but there is no such part on the rear ones so I can't see how the suspension bush would ever withstand 48lbft. As far as my car is concerned the connection part sequence starting in the engine bay is : bolt, large steel washer .... bolt through chassis leg (in tube as I understand it)... flat washer bush, sub frame, shaped lower suspension bush, conical washer, nut.
I've asked superflex for an opinion about this. Also the person who rebuilt the car 12 or so years ago. There are two different opinions.
One is the chassis leg has a protruding tube (extension of the tube within the chassis leg?) that passes through the washer bush and abuts the top of the conical washer, thereby you'd assume, enabling the whole thing to be tightened up to 48lbft in just the right way that its all tight and the suspension bushes are acting as a clamp but not compressed to destruction. The other opinion is that there is no protruding tube at all and the washer bush simply sits between the chassis leg and sub-frame with the whole thing appropriately tightened - 48lbft being too much.
So which is correct? There is no protruding tube on my car nor any sign there ever was. When I finally get to the OS one - totally inaccessible due to steering linkage - I will compare of course. I can't help thinking that if there was a protruding tube it would have to be exactly the right length otherwise it would either do nothing (merely acting as a locating spigot for the washer bush if it were too short) or would cause insufficient clamping of the arrangement if too long ie causing a bolted join between the metal parts and rendering the bushes useless). It just seems a stretch to imagine the mechanism would depend on this and that it would be reliable.
If it turns out a protruding tube is supposed to be there I have some awkward issues. I'm not sure how that would be accurately fixed and not in a rush to visit a welding shop anyway. Could washers be used ? But then of course there's the issue of what depth of washers would be required. If there is a protruding tube can anyone advise how much it protrudes?
Second question is much shorter. I'm also replacing the bush where the steering column goes through the bulkhead. Probably impossible to remove the column due to wiring bulk and so the parcel shelf will have to come out too. But the column is clear of the hole so I think I can work this without full column removal. The WM talks about two washers around the bulkhead bush - a steel one on the engine side and a plastic one on the inside. I assume to limit wear on the bush? I have the steel one but the plastic one is not there. Does anybody know where I could get the plastic one or, if I made something myself, how thick it needs to be and what material could be used to make it? (and what is the original made of? )
Thank you
Mark