What did we do before the internet? It was not that long ago that we had to learn stuff and remember things. Now information (or ‘alternate truth’ as can often be found on the interweb) is right at our fingertips. YouTube was short on Burman GB gearbox overhaul “how to” videos presented by a grey whiskered, fellow sheddy who happens to be doing the same thing as me, so old school it is then! Armed with a parts diagram from Draganfly, and some trepidation, it was time to see what makes the Burman tick and the Squariel move forwards.
I have been pushing my luck so far with tools for this job. I have a sum total of 3 x Whitworth spanners (covering 4 sizes), a fair representation of AF and metric tools, a small workbench, a bench grinder (powered by a hamster) and a decent vice. Knowing that I would face some hurdles with my limited workshop I put on the blinkers and determined that the best course of action is to figure things out as I go and we will see how far I get.
That said, I my luck has just hits its first speed bump. Pulling the gearbox down was not as difficult as I envisaged. There were a couple of bits that left me thinking that I will be doing some head scratching one the way back together (refitting the kick-starter spring for example) but all in all, it came apart quite logically.
Undoing the oil drain bung, all that came out was about a quarter of a cup of milky goop. Not a good sign. No noticeable metal flake in the oil but I was not too hopeful with what I was going to find when I got the thing apart.
First strike of working beyond my toolset. The oil filler plug was held in place with thread tape. Dang! First stripped thread repair coming up. I have used Keenserts in a former life and have always preferred them over the Helicoil style of thread repairs. Time then to brush up on my hand tool skills with some drilling and thread tapping to be done. Time also to head back to the internet to track down my old mates, the Keensert.
On the plus side, at first look, the bronze bushes look in surprisingly good condition with no discernible wear evident. The bearings, on the other hand, are a bit grumbly which is not unreasonable given they are 60 years old.
Toolbox limitation strike two! I really need a press to remove and refit the bearings. Time to break out the shed dwellers currency of choice, a slab of beer, and seek out a mate with a press.
What to do next?
Tomorrow I will give the internals a good clean up and see if my first assumptions are correct about the state of the bushes, find a press, a lathe while I am at it and order some more parts. Yay!