The Caterpillar 248B Skid Loader has three windscreen sections fixed together with structural sealer. It’s certainly not a job for the DIY technician unless you have the glass already pre purchased, or cut to size.
With that in mind we are not going to go into minute detail with the installation. We will assume that you will have enough understanding of the basics that you will not require a step by step.
In this case we cut and processed the windscreens onsite from one of our pre made OE templates. Cutting the right hand shaped windscreen is a challenging job even for an experienced glass cutter, so we will not be discussing the glass cutting and processing in this blog also.
The loader we had to repair had two of the three windscreens damaged. The right hand side and the centre windscreen.
|CAT 248 Skid Loader Windscreens|
First off we have to remove the windscreens. To make life easy we prefer to use the BTB glass removal system. It takes little effort with the BTB and it speeds things along ten fold. You could do this manually with a Olfa Knife or other manual tool, however, it will test your patience as it makes the job much more difficult.
For our US readers the BTB system could be compared to the Equalizer ® System. The do a similar job and we are sure it would be equally as efficient as the BTB.
|Main tools for the job|
The BTB system not only removes the windscreens quickly is also keeps them in one pice. This makes life so much easier as there is minimal clean up. In this case we used and old BTB-W4KS Blade. No need to use a new one as this kind of work does butcher the blade a bit.
Be sure to run a Stanley Knife or like down the two clear silicone seals first to split the windscreens from each other. In addition take extra care with centre windscreen removal as you do not want to disturb, or damage the unbroken section.
Once removed cut back the old adhesive to about 2mm high. Then cut and process the new windscreens from OE templates if possible.
At Service 8® Windscreens we tend not to use old removed windscreens for templates. More often than not the workmanship is not so accurate. If you take a further template from this work, each time you do so the glass fit is compromised a little. In other words, job quality is sacrificed with every copy.
|Use OE templates to cut windscreens when possible|
Stick some two inch masking tape on the inside and outside edges of the glass that will be bonded together. This will make a nice professional factory seal for the joints later. You could do this after you have installed the windscreens, however its much easier to do it on the table rather that on the machine. Don’t forget to tape the other existing window that is still on the machine too.
Important. When putting the tape on the glass the space between the tape and the edge of the glass should be about 5/8mm. This gives the sealer plenty of purchase on the glass when dry. I have seen many jobs were the sealer has been just pumped into actual daylight size of the gap. The problem here is it can be poked through, or fall out over time.
When using the BTB windscreen removal tool it can be a little aggressive so priming the body of the machine is absolutely necessary in order to prevent future rust.
|Always prime the steel body to prevent rusting|
Ok, now we are all good to bond in the windscreens. If you have used OE templates everything should be nice a snug with tight tolerances. The gaps to the middle windscreen should be about 5mm.
|Nice OE fit, Approx 5mm spaces in the middle|
The adhesive we use is Sika Drive. It has a one hour drive away time and will be stuck fast in about 10 minutes. As we don’t want to disturb the position of the newly installed windscreens you can now go off and do something else for 10 minutes. We use this time to pack away all of our equipment. By the time we are done, the adhesive has cured enough for use to work on the windscreens without disturbing them.
|Cut a nozzle as wide as the actual gap|
We tend to not pump the sealer right into the gap, but rather just hover the nozzle over the gap. This way the sealer is injected into the gap and on the edges of the glass too.
We use a structural clear silicone (no to be mistaken with bathroom sealer). Structural is not only stronger, but is weathers well and cures quickly. This is the kind used to bond fish tanks together. We have used many brands and we have no preference here, they all seen to work well.
When smoothing the adhesive first use a plastic flexible putty knife. On the first pass go very lightly. The idea is to work the adhesive into the gap slowly. This ensures a consistent finnish without air bubbles. Do the same on the inside as you will have now pushed the adhesive thought. Work this several times removing the excess adhesive each time. In the end you will have a smooth finnish.
Structural silicon cures quickly so only work with one gap at a time and work swiftly.
|Be gentle on the first pass to work in the adhesive|
Once you have done this put on a rubber glove and spray you finger with windex, or soapy water. Run you finger firmly down the sealer from the inside, then the outside. You don’t want to poke your finger into the gap but rather smooth the outside of the sealant. Once complete the result should be just like a factory finnish.
|Firmly run you finger down the sealed joint|
Remove the tape carefully and all is complete. The more time you spend with your preparation the better the end result will be. The more experience you have with kind of work the better you will get. However, if you take your time there is no reason you can’t get it right first time.
|Professional factory finnish|
|Service 8® Windscreens|