3 replies to this topic

[zero_wlv]

Hi everyone,

 

I've just finished replacing a nylon cup in the upper arm on the front right-hand side of my car  (it turned out it was absolutely fine anyway but a persistent squeak from the RHS had got me a bit paranoid).

 

To do this I obviously had to compress the donut and remove the knuckle joint and trumpet (which is a Hi-Lo).  As my donuts are fairly new the only way to get everything out is to shorten the Hi-Lo as much as possible.

 

The left-hand-side of the car remained untouched.

 

Everything went back together perfectly fine,  and I've wound the Hi-Lo back up to match the height of the LHS suspension.

 

I've just been for a 60 mile drive to test everything out,   it's fine,  except the steering wheel is pointing slightly (but noticably) left when the car's going straight ahead.   I think there's a bit more vibration as well.    

 

This has alerted me to the fact that changing the height of a hi-lo could have an effect on the tracking,  which had never occurred to me before but does seem logical now I think about it.

 

Tracking was fine before  (in fact was done by laser by a local garage about a year ago).

 

Note that I haven't DELIBERATELY altered the height of the Hi-Lo, but I can only assume that after putting it all back together the height I've achieved must be slightly different to what it was before.  How else could the tracking have changed?   (I haven't messed about with any other components such as the tie-rods).    Probably the two sides weren't completely level beforehand but it just wasn't severe enough to notice.

 

Is it normal to have to re-set the tracking every time a Hi-Lo is adjusted?     Surely someone installing new rubber cones would notice a MASSIVE difference in tracking but I've never heard anyone mention it before.

 

I have a Gunson Trakrite arriving Saturday so hopefully the tracking will be sorted,   but as it could be safety critical,   I'd also like to ask if Hi-los could have any effect on the camber or castor,  and if so do I need to do anything about this?

I've always understood Minis to have non-adjustable camber and castor so I've never given it a second thought  -  but having said that,  Minis weren't fitted with Hi-Los in the first place!

 

Am I ok to just re-set the tracking with a Trakrite and not worry about anything else?

 

I've searched the forum for anything to do with ride height and tracking but couldn't really find the answers.

Thanks in advance for any advice.

 

 

[nicklouse]

ok HiLos and ride height.you think you have set it to the correct height but i dont think it is. you may have it looking like it is but you have most likely got it not set high enough so that you have the same compression on the rubber. this is where setting the corner weights is important so that you the springs are evenly compressed as well as having the same ride height.

[zero_wlv]

ok HiLos and ride height.you think you have set it to the correct height but i dont think it is. you may have it looking like it is but you have most likely got it not set high enough so that you have the same compression on the rubber. this is where setting the corner weights is important so that you the springs are evenly compressed as well as having the same ride height.

 

Thanks nicklouse,  I used to work somewhere that had electrical load-cells for measuring the weight distribution of shipping containers,  which would have been ideal,  but I sadly don't have access to them any more.

Is this a facility garages commonly have,  and if so would I be talking 10s of £s or 100s or £s?

Am I being naive in thinking I should be able to measure the amount of thread showing on the hi-lo and equalising it that way?

[Spider]

 

ok HiLos and ride height.you think you have set it to the correct height but i dont think it is. you may have it looking like it is but you have most likely got it not set high enough so that you have the same compression on the rubber. this is where setting the corner weights is important so that you the springs are evenly compressed as well as having the same ride height.

 

Thanks nicklouse,  I used to work somewhere that had electrical load-cells for measuring the weight distribution of shipping containers,  which would have been ideal,  but I sadly don't have access to them any more.

Is this a facility garages commonly have,  and if so would I be talking 10s of £s or 100s or £s?

Am I being naive in thinking I should be able to measure the amount of thread showing on the hi-lo and equalising it that way?

 

 

 

 

You'll need a length of 40 x 40 x 5 mm angle iron, and camp that on to the rear rail of the rear subframe. Put some masking tape on the Vertical of that around the mid-point. Then accurate measure between the rear mounting points of the rear subframe and  make a mark on the masking tape.

 

The jack the rear of the car up, but, between the Jack and the Angle Iron, place something round, say about 10 mm in dia between them, so it can pivot on that.

 

Then measure from the floor (assuming your floor is flat and level and your tyres are the same type, same wear and same air pressure) to the very front bolts of the subframe to body (or teardrops) on each side. That will show how far out you are, side to side. Then you'll need to adjust, 'jounce' (bounce) the car a few times and check again, until they are the same. Ideally, you'd want to do the same for the rears too.