Hello all,

Firstly sorry for any repetition. I know certain details on this topic have been covered before but in the interests of safety and building my confidence I'm gonna ask again for clarification. Car is 6N2 1.4 8 valve petrol. Hopefully the picture I've used is from a compatible vehicle.

Sorry also to the persons photo that I stole before drawing all over it.

So I have axle stands and four chocks for the back wheels. My trolley jack is on the way and my offside front ABS wheel sensor as replacement.

As identified before - part of the problem is: at the point you jack you can't place an axle stand.

Need some advice regarding jacking and support under the front subframe - or anywhere else if there are better suggestions.

My plan is to jack at the reinforced points on the pinch welds and support with stands under the subframe. Or I could do it the other way round?

Where is safe on the subframe:

The only place I've tried to place axle stands is along the green lines. Does anybody think there are better positions? I would think yellow next (maybe better closer to the body) but don't know if orange or red are feasible? Is any place safe on the subframe?

I know I only need one wheel off but am I better to raise both sides anyway, for balance and stability? Could also turn the steering rack then too.

Really don't want to jack under a frame rail or the front corners behind the pinch welds - it just doesn't feel right in my head.

Any help appreciated. Many thanks in advance.

Simon

Edited 24 February, 201610 yr by cosaw

These are the official points

If your going to be turning the wheel then it will be best to lift both sides for safety

As identified before - part of the problem is: at the point you jack you can't place an axle stand.

Personally I use the jack where the control arms connect to the subframe and then place stands under the pinch welds. I recall being told you should avoid lifting at both control arms and subframes themselves, but where they connect is a fairly strong point. I've lifted the car multiple times over the past few months and it hasn't damaged anything anyway (6n1)

Hi nige - thanks for the input, appreciated! What's the source for your drawing? I'm still not completely comfortable with it - it seams a bit vague. If it refers to the reinforced pinch welds then it makes sense but still doesn't solve my problems. If it also indicates parts of the floor suitable for jacking then it is definitely more vague. Correct me if I'm wrong but the spots in front of the rear trailing arm bushes make perfect sense as their is square downward protrusion that will fit on to the jack head or a jack stand - it's the same position down the rear of the car as the reinforced pinch weld indicated with the arrow on the side of the sill for the emergency jack. This square protrusion is also indicated in the Haynes manual with a jack stand underneath.

Rear, square downward protrusion etc. (see comments further down too with relation to picture):

The VW Handbook is completely useless. At first it seems to make sense but then their are several places where it contradicts at different points in the manual. The only consistency is that it points to the pinch welds only as jacking points but it can't seem to decide how far down the pinch, from front and back arches, is safe to use.

Vio, many thanks for your input. Can you clarify what you say as I'm a bit unsure.

I use the jack where the control arms connect to the subframe

So that's the front of the bits I've marked with green? And is as you say where the control/lower suspension arm meets the subframe?

I recall being told you should avoid lifting at both control arms and subframes themselves,

Not sure what you mean. I wouldn't consider it safe to lift anywhere on the control arm - am I wrong? Do you also mean don't lift on both sides of the subframe. For example in my picture - don't place a stand under one green line on the left and one under the other green line on the right - suppose that's the most likely time it would bend. So that would mean use one side only of the subframe and another stand somewhere else or the other wheel on the ground.

Is axle stand a completely stupid name - should they ever be used under axles? Should we refer to them as jack stands?

When I come to do the back brakes I'm gonna have similar problems. At first site jacking under the rear trailing arm bushes looks suitable as the weight of the car goes through the bush anyway. Yet the VW handbook says: Under no account should the vehicle be lifted under the engine, gearbos, rear axle or front axle as this can cause serious damage. So I guess under the rear trailing arm bushes counts as the rear axle?

I'm hoping when my jack comes it should become clear for both front and back. Hoping at back I'll be able to jack under the square downward protrusion and then support under the reinforced pinch weld.

In the meantime I'm cutting slots in some hockey pucks for the pinch welds.

Sorry to go on but I just feel it seems to be a subject that's not much talked about but is somehow taken for grated by those who know. I understand there will always be disagreement and I think some people are afraid to give their comments because it's such a safety critical area. At the end of the day we all need to use our common sense to make our own decisions but sometimes things are not always obvious - especially things that shouldn't be done. Suppose I just really want to stir up some more debate from those with good experience.

Edited 25 February, 201610 yr by cosaw

In that picture, the square point is where you should jack it on, the reinforced pinch weld is where you would use the "widow maker" standard car jack, On the rear I put the axle stand on the point in your picture where the axle beam bolts to the shell, at the front I would put the axle stands where the track control arm rear bush bolts to the subframe.

My picture was from the Autodata manual

Hi Nige - thanks for your continued help. I've altered the pictures and drawn some purple rings on the subframe and a purple section in the second drawing also just to be sure. Are these the points you refer to in your last post?

Yes, they are where I would put your axle stands, If your need to do work on the track control arms then put the axle stands on the chassis rail behind the subframe

That's excellent Nige - really chuffed you could help. So to be sure - the chassi rail, like you say, starts behind the subframe and is, part of/runs under, the monocoque - it's real hefty at the front and runs down the bottom of the car from the front to the back?

It's a while since I looked under a Polo but yes the chassis rail runs from behind the subframe towards the rear it's about 50mm across so it sits nicely in an axle stand and it's probable the strongest part of a Polo :)

I usually jack under the subframe somewhere and put stands on the chassis rails as axle stands/jacks on the sills often mash them up a bit

A couple of points: The name 'Axle Stand' dates back to the days before independent suspension, when cars had solid beam axles at the front and the drive was to the rear axle, both of these being ideal support points (unless you wished to remove either axle, that is.) The name has stuck - probably because the stands are still of the exact same design.

What you have labelled as a 'square downward protrusion for jacking and support', are not all that strong, worse still, these tend to suffer from rust before other areas do. I believe that the purpose for these 'protrusions' was for handling and aligning the body whilst in the factory.

Like yourself, I have made an adapter to fit the head of the trolley jack. I made my own from a piece of 'Dural' that I happened to have, cutting a cross in one face to fit the jack head and a slot in the other to accept the lip on the sill. I then screwed some thick plywood to the side which contacts the car, in order that it would be kinder to the paintwork/underbody protection.

After I have finished supporting the car, I make a habit of checking the paintwork for damage - prevention being better (and easier) than cure.

Regards

Thanks for all the advice guys. This thread is really getting going with some good stuff.

Appreciate the advice about frame/chassi rail support and the explanation of the term 'axle stand' which I did want answering - I thought it was something like that but really wasn't sure.

I'll take note about the 'square downward protrusion' as we're calling it. Corrosion is one of the first things I thought about here as with anywhere I'm going to lift or support.

Not sure what Dural is but it seems to be some sort of tiling product. Thanks for the details caretakerplus. Trying to work out the plywood bit. On the single slotted face you made one of the sides, that make up the slot, taller with plywood? That was also the side which goes under the car first before raising to fit the pinch weld? I have noted down the length of the pinch weld that the 'floor' on either side of the pinch weld is not necessarily the same height meaning that any slotted rubber pad is not always a perfect mating face.

The square shaped protrusion in front of the rear beam mounting point, is I think you will find what the manufacturer uses to mount the car on the assembly line when being built, a similar thing ( well a flat plate about 13mm below the floor) are on classic mini's these are shoe slinging points and used for locating the car on the production line during assembly you always find them flattened by some genius using them as a jacking point. even though there not strong enough. If you want to use wood as a packer between either a Jack or axle stand and the car to spread the load and/or to prevent damage to the car, I use a piece of cut down CLS batten this is the stuff you use to make the wooden frame for dividing walls in a house readily available from B & Q. As with anything you use to lift or support a car ensure it is secure before carrying out any work, you can always place a wheel that you have removed of the car under the sill as an extra safety precaution in case the car did come of whatever is supporting it.

Dural is an aluminium alloy of great strength and also makes an excellent bearing material - in the past, con-rods have been made from it.

If you look at the majority of 'wheel free' vehicle hoists in garages, you will find that they use a thick 'rubber' pad between the metal part of the hoist and the underside of the car - In most cases this is OK, but it is possible for the lip of the sill to buckle when lifting.

The plywood that I mentioned is attached to Dural by drilling/tapping the metal and attaching the plywood with countersunk machine screws, so it is easy to replace it if it becomes damaged.

Ian131 makes a good point about placing the road wheel on the floor under the car 'just in case' - this is a practice that I have followed for years.

Regards

Yes wheels under the sill is noted. Yep CLS is good stuff too and easy to work with.

Ahh, Dural as in Duralumin - I think they used to use it in the aircraft industry. Thanks for the explanation on the Dural/Plywood construction - I get it now.

Well I'm feeling more confident now about the situation. Many thanks for the info and feel free to keep any pointers coming - I think this could be a really useful thread for people.

Bit of a progress report. Put on ramps first to check around where I was gonna jack. The bits with the purple circles in the picture above were a bit rusty and so I went with jacking where I drew the green lines. I then used wooden block with slot and jack stand under the front reinforced pinch weld jacking point. Supported one side of the vehicle. Still taking things gently.

If a moderator wants me to start a new thread then let me know cos the progress report goes off on a tangent here with regard to loosening stuck fasteners.

That's as far as I got with the bad weather. Some progress though. While on ramps I noted the 5mm allen bolt securing the abs sensor which currently doesn't want to accept a hex bit due to corrosion. So tomorrow I'll get on stands on both sides so I can turn the steering and get to parts I need. Think I'm gonna need caliper off and those are 6mm allen bolts. Bit concerned on loosening them too. I saw this youtube vid: https://www.youtube.com/watch?v=lIdCyYco6AI

The video suggested you needed to go carefully with the 6mm allen head slider pins. Seem to have rubber on so I can't use heat yet unless the rubber is removable. Can I use heat on the slider bolts at the other end though - think that's the thread end?

Seen a few youtube vids too where the 5mm allen bolt for the abs sensor doesn't come out full stop and have to saw the head off.

So plan is to get a wire brush and some penetrating spray round the 6mm slider pin hex ends and the 5mm retaining hex head on the abs sensor.

Any advice appreciated.

These are what I used on my seized slider bolts

You can buy the rubber sleeves from VW/TPS or Biggred

Cheers Nige although I think they're not what I'm after - aren't they for bolt heads? Been doing some research and I think mine aren't like in the video above. I took a pic this morning:

Think I'm gonna have to get brave with an allen headed socket. It looks like penetrating fluids aren't gonna get anywhere near the threaded end and may contaminate the silicone grease on the sliders if they did get in.

I believe my caliper is this type (top one): http://www.eurocarparts.com/brake-caliper

And I think now my slider pin arrangement is this type: http://www.ebay.co.uk/itm/VW-Polo-1985-2001-Front-brake-caliper-guide-pin-kit-slider-pin-kit-bolt-S7025-01-/331744231675?fits=Plat_Gen%3A6N2&hash=item4d3d7f40fb:g:wq8AAOSwe7BW0Mee

That ebay link is not for the correct pins, as they are different lengths

171615221 guide sleeve 45MM /

171615221A guide sleeve 35MM /

N 90329104 allen key head bolt M8X49 /

N 90329205 allen key head bolt M8X59 /

That tool works perfect on these bolts as they are intended for removing bolts/studs so they grip on the pins and mine came out without any fuss :)

171698447A 1 set: guide bushes These are the rubber covers and the PTFE liners for the guide sleeves above

Cheers Nige. Bit confused now as I could have sworn a 6 mm allen wrench was fitting. Need to look over the brakes tomorrow or when there is good weather and confirm sizes.

Will check over your part numbers tomorrow too.

So in my case I'd tear the rubber off before using the removal tool over the outer head of the allen bolt?

I just pushed one those removal tools over the few mm's of the bolt showing above the rubber and it gripped OK then I removed the caliper and fitted the new guide sleeves with the PTFE liners and new rubber covers

Raises more and more questions as usual. Yes I think you're right I pointed to the wrong length pins - there are other sets.

Regarding sizing - like you say it seems to be an M8 bolt with a 6mm hex head. Why they didn't just put a 12 mm bolt on the end I don't know.

With the PTFE liners do you still use silicone grease?

So for the laser bolt remover set did you need to use an impact device? Do you hammer them on and then just get a spanner on the end?

Think might be worth a try on the abs sensor bolt first:

Got an impact driver to remove the Philips grub screw on the disc so hopefully that will go ok.

I tapped the tool on with a hammer and then used a 6mm / 1/4" spanner on them and it just wound out

I did use grease with the PTFE liners just to reduce the corrosion possibilities

Thanks for the details Nige. I've got the drivers side of the car up at the moment. I tested the continuity of the wire from the wheel back to the abs control module. Both sides read good at 0.5 ohm and give a clear beep. Resistance of dud sensor was like 2.6 meg ohms so got to be dud compared to just over 1 k ohm for a good one.

I did a dummy run and plugged the new sensor in but left it handing and connected all electricals up and turned key to position 2 making sure I was out of gear. I didn't start the engine but the abs light still stayed on. So do I have to start the engine for the fault to clear? I'd prefer to do that once getting both front wheels off the ground just in case - is that safe? Will the fault clear then or does the sensor need to be fully in and the car running down the road?

Thanks for all your help Nige.

You can clear the fault code with VCDS or it might reset on it's own once you have driven it at more than 20mph

As long as both front wheels are clear of the ground then it's OK to start the engine and even put it in gear and spin the wheels up :)