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Showing posts with label A-Arm. Show all posts
Showing posts with label A-Arm. Show all posts

Installing a CSP Torque bar

31st October 2008

After modifying the bodywork of the car during the installation of the IRS components in preparation for allowing the A-arms to rise and have enough clearance I had decided to cut the body work high enough for the CSP bars to fit. The main reason for this was I was trying to stiffen up the rear suspension. The IRS fitting process meant that the Frame Horns had to be heated an bent to accomodate the drive shafts. This took some strength out of the Frame Horns and the CSP Torque kit would imrove this ensuring the floating Frame horns where locked into the rest of the chassis.

I had detailed the body work that needed cutting in a previous article and will not cover it again in this article. The main reason for the body removal was to eliminate a portion of the tyre well that came into the area the CSB Torque bars will fit into. This problem is only associated with my style of fibreglass bodywork and is not neccessary if you are using the standard beetle body.

After cutting the body work down I found that it was very difficult to get hold of the CSP Torque Bar kit. I did not want to import a new one from CSP as this was quite expensive and had luckily found one on eBay only to find that the seller was not really interested in selling it and was wasting every ones time by shilling the bids at the last moment so unfortunately I had to let that one go. A month later I had been watching eBay and all of the usual sale sites for some time when I saw the CSP kit above advertised. I secured it along with the rear gearbox mount. It was in excellent condition and all the welding work had been done and the mounting plates had been anodised in a gold zinc coating. This did not appear to be paint so I presumed it must have been plated.

The installation of this Torque bar kit is fairly straight forward the welding that is usually needed for this installation is detailed here: http://www.csp-shop.de/technik/pdf/deeng/20917.pdf You can see that the three bars triangulate the frame horns which support the gearbox cradle significantly reducing the flex that gets put into them from a high performance engine. The bars being made from Aircraft grade aluminium make the adjustable bars are very strong.

The rear cradle that supports the engine and gearbox is securely bolted to the frame horns by two large 36mm fine threaded bolts. They can really only be got at easily with the engine removed from the car. Considering this is a simple process of disconnecting the throttle cable and then undoing the four bolts, this is where we will start in my installation of the welded torque bar.

With the engine bolts removed and the throttle released the engine will sit on a jack above a plank of wood. This will hold the engine whilst it is still located on the final gearbox drive shaft. Be advised it safer for two people to help removing the engine. The engine can be slowly drawn and wiggled backwards off the final drive shaft in the gearbox until it becomes disengaged. The engine will then be solely supported by the jack and it should be slowly lowered to the ground with the engine nearer the ground. Ask your friend who has been helping you stabilise the engine on the way down to help you lift it from the jack onto another plank of wood. This should be easily accomplished but ensure if you are following this that you use the proper lifting techniques so not to strain your back. The engine long block should now be removed exposing the gearbox.

The gearbox is mounted between the rear frame horns inside the bell housing at the bottom where it meets the cradle there are two bolts that hold the gearbox rubber mounts to the gearbox. Undo these and secure the bolts and washers for later use.You will now need to place a jack under your gearbox to support it . Again place a piece of wood between the gearbox and jack to prevent damage. Ensure the jack is biased towards the rear of the gearbox near the bell housing . With the jack in position you will need to remove the lower rubber gearbox mounts on one side of the gearbox. This will allow the gearbox to be lifted out. Use the jack to raise the gearbox out of its cradle.

The gearbox should now be disconnected from the cradle and the cradle can be removed by undoing the two large 36mm bolts that hold it onto the frame horns. You will need considerable force to undo these bolts. Use penetrating fluid like plus gas to soak the bolts for a few hours before you proceed. If your lock the you will already have a long bar that you can use as an extension to your socket set . you will need at least three foot or a metre of something like scaffold pole or if tour lucky an air powered impact wrench. With the cradle free from the frame horns you can start re-assembly with the new cradle. Ensure that you re grease both the threads in the frame horns before you bolt on the cradle. If you had your torque kit bought as a kit that you can assemble You will have two holes on each side of the cradle that take the mounts for the diagonals. These bolt on with the Allen bolts supplied. If you are having to make your mounts follow the CSP article to locate them in the correct axis. Replacing the gearbox into the cradle is the reverse of the removal process. You can bolt one or both of the rubber gearbox mounts on the side(s) of the bell housing. Then lower the gearbox back onto the new cradle.

The top mounts for the Torque bar are located of the suspension damper arm. To fit them you must removed the top damper mount. To access this you will find it easier to remove the wheel on the side you are working on. With the first wheel removed you should easily be able to find the damper and the retaining bolt at the top. The suspension system is under load and although you can remove the nut from the bolt you will not be able to remove the bolt without remove in the load from the torsion bars that is applied to the swing arm. You can buy a tool from VW heritage to pull the spring plate upwards although this is fairly expensive and is not used very often. I have found that you can use good quality luggage straps to do the same job. The luggage straps have locks on them that allow you to wind up the strap under load. If you are buying these get ones bigger than an inch in size with metal buckles. Loop the strap over the arm and back around the spring plate you should be able to ratchet the strap up to pull the spring plate up. You only need to achieve a few mm as this will allow the top damper bolt to be able to be slid out and the new longer one slid in its place. The damper can then be slid back onto the new bolt. The top mount can then be slid onto the bolt and the whole assembly can be bolted up. If you are not using prewelded assemblies then you will have to just pop on the bushing and follow the CSP installation instructions to weld the mounting tabs in the correct axis. This can then be repeated for both sides. It is easier to hold the car on axle stands whilst you are removing the wheels this allows you to remove both wheels and work without having to put on a wheel and then jack up and remove the other. With the mounts in place the bars can be attached using the supplied Allen bolts . Beware if you have wound out the threads on the bars that these are handed and are not reversible.

Assembly or the A-Arms and spring plates

30th May 2008

I had already cleaned up my A-arms and spring plates by sending them away to be media blasted and then zinc plated and rebuilt them with their respective bearings and axles. With the A-Arm mounts welded in place and the gearbox made to fit the frame horns I was ready to re-build the read suspension. I decided after a great deal of debate that I would refit all the bearings with the Urethane type. Popular research at the time indicated that the Urethane substance was good as a bearing surface and stronger than the rubber alternatives. I ordered two A-Arm Urethane bushes and new spring plate bushes in Urethane and two new cover plates. The all arrived from SSP quite promptly.

I started with the Urethane A-Arm Bushes These are quite easy to install and can be pressed into the arms with a reasonable sized vice or cramp. SSP does not sell its bushes with Urethane grease and It is fairly common knowledge that normal motor grease will slowly wear the Urethane bushes faster.

Once I had the bushes in place I was able to put them aside and make a start on putting in the spring plates. The inner bushes where pressed onto the inner side of the spring plate and then the knobbly outer was placed on and driven onto the spring plate with a wooden mallet. I had previously bought a digital level and had used this to set up some angles on the A-Arm brackets. This had proved to be a good method and as I new that the spring plates should be set at 20 degrees I found them fairly easy to get set up in the right position. I set up both sides so that they spring plates where pushed in tight . They needed lifting over the bottom of the block on the torsion bar end. This should really be done with a special tool to lift the spring plates. I used small luggage straps around the suspension arm and the spring plate. These are the ratchet type that can allow you to ratchet up the spring plate to maneuver it over the bottom hump so that it can be driven in with a mallet further into the torsion tube. Once the spring plate had been hit into position so that it fits into the shell at the end of the torsion tube. You can fit the spring plate cover with the four bolts before releasing the straps. This can be repeated on the other spring plate . The shorter spring plate design makes the force needed to pull up the spring plate more than the amount usually used.

With the spring plates fitted the A-Arms can be pushed into their brackets with the bolt pin securing them. This allows the washers to be placed in situe. i placed a washer ether side of the bush. Some people seem to place the washers on the same side but I figured the washers should be placed on either side.

With the bolts pin loosely done up I was able hoist the A-Arm up so that it was at the same height as the spring plate. This allowed the three bolts to be placed in the holes and tightened up to 11kg m or 80 lbs ft. With the spring plate bolts torqued up you can use an Allen key 87 lb ft 12 kgm.

Next I would have to install and make up the drive shafts.

IRS Conversion - part two

24th March 2008
Previously in the last article I have cut away the body to allow access to install the IRS brackets which are part of the IRS conversion. I had downloaded the Internet article at http://bajaclub.co.uk/PDF_Documents/IRS.PDF from Airsouls. Although this article was written quite well it did not adequately explain the process of cutting in the brackets. As this is the most important part of the IRS conversion this was something that I would new to spend time over.

The first thing which was obvious about the installation was that I would have to either buy; make or borrow a jig that would give me the proper position of the IRS brackets. Fortunately after placing an advertisement on Vzi I was soon in the position of two IRS jigs. One thing I have found with using other peoples jigs is that as you haven't made the jig, its really important to ensure that you know how it works and more importantly if it does.

I decided that I would have to try the jig on a 1303s chassis to ensure that the jig was correctly aligned. It was noticeable straight away that 1303s brackets where different to the ones that are available today. The other obvious difference was that the frame horns seemed to be a different shape . The jig fitted into the IRS brackets on the 1303s chassis . The noticeable thing about the jig on both sides was that the tube that was attached to the end was short on both of the jigs. The reason for this was that the jig would not be able to fit into the bush on the furthest end of the bracket if it was any longer. I returned home happily in the knowledge that the jig was ok and a reasonable fit.

It was at this point that an child hood illusion was shattered. I had always thought that VW cars where superior because they used the metric measuring system way before we adopted it in the UK. When trying to locate a suitable bolt that would fit the brackets this turned out to be 1/2" UNC. Well as you can see the myth was not true.

I took the jigs back to the garage. The first thing I needed to do was to cut away the metal where the bracket fitted into the frame. You can see in the pictures I started by removing material from the flange that braces the frame horn to the torsion tube. I took the material away to the handbrake cable guides. I new I would have to remove more material and take the flange back further before the bracket would fit in and not foul the IRS Arm when it was in place. The next thing I was going to have to do was to use the jig to locate on the bolt hole on the side of the frame arm. To do this the jig would have to be placed on to the car.

I needed to remove more material from the flange on the frame horn so the length of the bracket would fit alongside the frame horn. With the Jig in place on each side the and done up enough for the arm of the jig to make contact with the frame arm. I could use a black marker to draw around the outside of the bolt hole. I then used a Starrett 1 3/4" or 32mm type hole saw to cut out the hole were the bracket protruded through. It is important to note that when you mark the holes you have marked the circumference of a circle.You must ensure you have a centre point of this circle before pop marking and drilling. This can be achieved by using dividers or compass. The hole can be troublesome to cut out as it is very tight to get a drill and Starrett hole saw into you may find that the only way to do this is to purchase right angle conversion for your drill, these are exceptional for getting into tight spaces. The one pictured right came with a key less 10mm chuck for £9.99. I added an £18, 13mm keyed chuck onto it so that I could fit the Starrett arbour which was 1/2" into it . With this hole cut out the bracket could be slipped into this hole and positioned on the rear torsion bar to gain its eventual position. I used this method to locate the position of the bracket on both sides. The main reason for this was that on the Baja club IRS conversion the hole was made too large. Additionally the bracket did not sit entirely in the hole so it had to be cut out precisely. The angle that the brackets protruded from the torsion bar where then compared and adjusted so they where the same, luckily no adjustment was needed. I cut the holes out easily and tried the brackets on each side. I found the driver side (left picture) still required more material to be cut from the flange to allow the bracket to be fitted and marked. This bought the flange under the handbrake cable and would mean that the cable position might need to be changed. It appeared different from the passenger side as it was not interfering with the bracket like the drivers side was.

With the holes cut and the bracket positions marked. The gauge of the metal could be seen easily with the holes cut and looked to be no more than 2mm. I could start removing material from the torsion bar end working towards the rear of the car. This was going to be a slow procedure of cutting a strip back then trying the jig and bracket in place until a good fit was made. I would start by removing half and then use smaller increments on each cut back. I new the end of the bracket was supposed to sit outside the frame arm thankfully to a picture in the Airsouls article on the bajaclub website.

Once the brackets where made to fit, the jig and bracket where then fully done up in preparation of the brackets being tacked in place. Before they where tacked in I went back and took more measurements of the original brackets to ensure everything was in line and in place. When I tried to get my Arc welder running on my Honda Generator I soon found that it drew too much current from the generator to weld with. I would have to hire a welder generator for machine hire company to allow me to get the brackets welded in and the new A Arms fitted.

Cont.

Rear Body Modification

12th March 2008
After the first attempt at installing the IRS brackets I realized that the rear body dropped quite low into the area where the new IRS A-Arms where going to fit. I had already cut down the drivers side battery box and removed the side of the frame horn ready to use the IRS bracket jig. I had been thinking about the frame horn trusses and new that they needed to fit between the upper shock absorber mounts in addition to needing to create space for the passenger side A-arm to move. The spare tyre well placed a bulge on the underside of the body that was directly in the way of any bar that would traverse the top shock absorber mounts. I was already committed to rebuilding the battery box bottom and decided that whilst I had access to the rear of the car that I would cut out portions of the spare tyre well laving enough space for the new IRS parts and the frame horn truss to fit. You can see from the two images above the differences in the bottom profile of the buggy. The height of the rear projections in to the chassis had been reduced substantially.

The picture to the right shows the inside view from the rear seat area. You can clearly see that the cut-outs follow the line of the battery box. With the areas rebuilt and the rear shelf extended to meet the new back of the spare tyre well area. This hopefully would leave enough clearance for the frame horn truss to be fitted, if and when I managed to find one for sale at a reasonable price.

Finally I was nearly ready to see if the new gearbox fitted.

Installing the IRS A-frame brackets - part one

11th March 2008
The fabrication of the Jig for locating the position of the IRS A-Frame brackets was not something I needed to do as I found a seller on www.volkszone.co.uk , who was wanting to sell the jig he had for building his own IRS. I picked up the jig from him and was soon aware that he had not used the conventional bolts that bolted the A-Frame in to position the brackets. The tubes that ran inside the brackets was only the size of a 1/2" UNC x 4" bolt. This did not give a steady position for the brackets and I decided that before using them I would have to check them against a real IRS chassis to ensure that they gave the correct position in practice. This would not be a problem as I new the location of a 1302s chassis that was bare at a friends workshop.

I decided that I would not be able to fully position the brackets, but decided to clean up the frame horns and remove the surplus material along where the bracket would sit. Once I had the jig problems resolved I would be able to cut into the frame horn to get the final position of the bracket.

I started with the off side of the car removing the brake hydraulic lines that where still left. It was pretty clear at this point that my battery box was to low to gain access to the bracket position. I was also worried that being so low the A-arm would hit the bottom of the box as the suspension moved. This was not going to be an easy process with the body attached to the car, but I decided it looked feasible. I started by drilling a hole in the fibre glass that I could push the blade of a jig saw through. This allowed be to cut along the back and the inside of the battery box several inches from its bottom. I then managed to use an angle grinder to cut from the inside of the box the outside edge of the battery box. The angle grinder was also able to cut the box around the torsion bar, which enabled the bottom of the box to be removed.

With the bottom of the battery box removed I had access to the flange that ran along the outside of the off-side frame horn. I started to cut the metal with the angle grinder and cutting disk alongside the handbrake cable. I was able to cut the material back all the way to the torsion tube. When I had finished cutting this area out I switched to a grinding blade and cleaned the of the paint. I knew I would have to build a new floor to the battery box at a later date but I was pleased with the progress I had made with the drivers side.

The weather forecast for the next few days was awful and I was not able to get into the garage to cut the other side down. I had decided I wanted to cut the fibreglass on the nearside of the car , which was rumoured to be for a spare wheel. This was ludicrous of course as there was no way a beach buggy wheel would fit in this space. The main reason for removing this area was to allow for the future placement of a German Kafer Cup type Torque Bar Kit. As seen on the left. The design of this needed to allow a bar to cut straight across the spare tyre well and under the rear seat rear of the buggy. Currently this was an expensive piece of kit and I wanted to see if I could build in space for it to fit should I be able to get hold of one or build one.

The weather was suspected to get worse so this was all put on hold for better weather conditions that where more favourable as the high winds had nearly took the garage door off already.

Rebuiding IRS arm bearings and axle shafts

3rd March 2008.
With the urgency of pulling the engine out now gone and the engine now sitting waiting to be rebuilt. I decided that I needed to get on with the IRS conversion that I had already started before I found the problem with the debris in the crankcase.

I decided that I was going to renew most of all of the components on the A Arms. This meant I needed to purchase new bearings oil seals and other miscellaneous sundries.

I started with trying to locate the bearings, several telephone calls later I was wondering what's was happening to the parts industries. The only bearings that it seems that I could buy where the new type of needle bearings. This was annoying as I already new that roller bearings where much better and ran much smoother giving less drag and longer life.

The problem being that the needle bearings where made from small cylinders that run in a steel cage made from pressed steel. The ball bearings on the other hand had small spherical bearings in a cage made from several parts. The friction surfaces where much smaller and the tolerances in the bearing where much higher.


Needle Bearings (above left) ............................... ,Ball Bearings (above right).

In the pictures above you can clearly see the differences in the two bearing designs and why the ball bearing or ball race provides less friction and better wear.

After discussing this problem with come friends I found out that you could purchase bearings from a bearing company and that they would usually measure your existing bearings and come up with a match. I found a company called Kent Bearings in Hastings East Sussex. They provided me with the correct size bearings. Interestingly enough the two bearings sizes where the same. This was interesting as most car suppliers supplied the rear set of bearings at a higher cost?

I bought the bearings and bought some Castrol LM bearing grease. I found that the oil seals came in a kit for the cars with swing angle and not for IRS. On closer examination the parts in this kit where exactly the same as the parts that could be sourced separately for the IRS.

The Axles are assembled from the back bearing. This is inserted first, then then the circlip and then the oil seal. All of these items need to be greased with the LM lube before they where assembled. Once these components where set in place the inner spacer (The spacer with the concave side was placed into the oil seal with the concave side facing the outside. The axle was thoroughly greased and then knocked into the A-Frame with a wooden mallet. 6oz of LM grease is then packed into the front of the A-Arm cavity. The inner spacer can then be lubricated and slid onto the axle. Once all this has been done you are ready to insert the outer bearing. This is slightly harder to achieve as you need piece of tubing the size of the outside bearing casing and about 250cm long. You can slide this over the axle and then knock the lubricated outer bearing into its place. The oil seal can then be seated over the bearing and the external spacer can be set on the axle and slid into the oil seal.

This process leaves you with the axles correctly installed in the A-Arm. You can add the cover plates at this point but I wanted to get hold of some calliper brackets before I placed them firmly in place.

Parts.
Grease: Castrol LM Lithium grease
Ball Bearings:
FAG 6206.c3 15010719