Changing Front Wheel and the scissor jacking point?

[callumskeat]

Folks,

Where do I jack on the wishbone for changing a front wheel using a scissor jack, I’ve only ever used a trolley jack before. A photo would be really helpful, I do not find the handbook clear enough. I’m thinking changing wheels en route to Tuscany this summer.

Grateful for some advice?

regards

Callum

[Jim 123]

Place the jack under lower wishbones front tube, with the tube sitting comfortably in the scissor jack face groove. It is worth putting something between the jack and wishbone to protect the powder coat and discourage slipping. Position the jack as close to the lower wishbone front inboard mounting as you can. It's not a confidence inspiring arrangement, particularly as the the scissor jack design is intended to lift tin tops by being placed at 90 degrees to the car longitudinal centre line, unlike the Caterham solution.

[Jonathan Kay]

There's a different location suggested in this Low Flying article.

I have no idea of the advantages and disadvantages.

Jonathan

[Jonathan Kay]

I’m thinking changing wheels en route to Tuscany this summer.

There's a lot of helpful people out there... do you know where you'd like to do this?

Jonathan

[callumskeat]

Folks,

Many Thanks, Just what I needed.

Regards

callum

[Tony P]

I wouldn’t want to put the jack under any part of a wishbone at all. I’ve seen people put the jack under the bottom of the upright - but that only works with a trolley jack with a ‘cup’ rather than the tiny top of the scissor jack.

You could put a stout length of wood (a long-enough pice fits into the boot) laterally underneath the lower cruciform of the chassis (do recent cars have that feature in the spaceframe?) and jack the car up centrally from underneath the wood.

If you’re going to do this “in the field”, so to speak, I’d place the/a spare wheel in a suitable place under the car while it’s ‘up’ - then if the car does fall off the jack you will have a)less chance of damaging the car, b) less chance of crushing a hand or limb, and c) some space from which to retrieve the jack and start again.

[garybee]

That Doesn't look safe to me.  If I wanted to use a scissor jack on a seven I'd make a small 'sill' from a section of 90deg steel angle and bolt this to the chassis using the two bolts holding the engine mount.  You could then use the normal style scissor jack without any concerns about dropping the car.  Crappy paint drawing to follow.

Edit: something like that, 10min to make a couple of those with some steel section and an angle grinder.

[Jim 123]

I like the idea.

[SLR No.77]

For a scissor jack the arrangement that JK has referred to is the safest, ideally carry a small piece of plywood (with two holes drilled) to fit over the engine mount nuts, this will prevent metal on metal (jack on chassis) and aid the security more.

It is not safe to use a scissor jack at the chassis end of the wishbone, the wishbone is a moving part and as the car is raised there will be some droop making the jacking point unstable. If jacking under the wishbone the jack needs to be towards the outer end but this is still not recommended with a scissor jack which is inherently unstable anyway. I've used a trolley jack under the wishbones for years with no detrimental effect on the tubing, I always position the jack under the outer half of the wishbone tube, ie. nearer to the wheel to keep the suspension under compression.

Wherever you choose to use as a jacking point, the jack must be as close as perpendicular to the jacking point as can be achieved to prevent slip and the force must be directly through the jack - remember this may not always be a true vertical line as the car is lifted.

Stu.

[Jim 123]

Has anybody had direct experience of changing a front wheel using the CC supplied scissor jack as per the handbook instructions?  It is certainly not a confidence inspiring arrangement.

 

[Wrightpayne]

I think garybee’s idea is brilliant - very simple like all the best ideas! I think the vertical edge and the two bolts protruding should stop the jack head slipping too far.

Ian