I started welding the diff first doing very small welds with MIG:
Next I removed driveshafts and started to weld with electrodes (312-17 / LIMAROSTA 312 2,5mm). This is very time consuming process since I only can weld a short while until I need to cool down the diff because I don’t want to let it too hot. Today I was able to do the first deep welds for each 4 corners and both sides, totaling to 8 welds and some 10-15min cool down between each weld. Next I will weld more and try to adhere the gears properly to the frame.
Seems that choosing electrode welding was the right choise since there is also small amount of plastic behind the second largest gears. Mig welding would have been very spotty because of that. And also those electrodes which I’m using seem to be very easy to weld and able to melt the steel deep so the gear teeths are disappearing (melting) easily to one lump of steel. I will probably continue this at Saturday since tomorrow will go with other activities.
Yesterday I was investigating my Sierra’s steering since it has started to keep annoying noise sometimes when turning the wheel and seems that there are something wrong with the tie rod… So I prepared a spare tie rod from my parts stock pile ready which I will remove&replace next Monday.
Today I built a fork that I will use to press diff bearing out from the speedo gear side:
My plan is to first weld the diff gears very lightly together with the drive shafts in to get the gear positions correctly. Then I will remove the driveshafts, speedo gear and bearing from speedo gear side. The big gear and bearing behind it I will leave in place. I will try to limit the amount of heat somehow, probably I need to weld at small parts and wait for cooling.
Since the driveshaft outputs from the gearbox will be working as cardan axles instead of being driveshafts I decided that I need to do something to the diff inside IB5 gearbox. Without doing anything to the diff the 4×4 drive system would be flawed since only the wheel that is rotating most easiest (the wheel on air usually) would get all the power.
So basically without any locks at diffs only one wheel of four would get the power and the tractor would be rather crippled. Now when I weld this “center diff” there will always be two wheels getting the power. One at front and one at rear. So this will be continuous 50% / 50% 4×4 vehicle (front/rear).
And at rear I do have viscous lock inside the diff so basically there will always be 3 wheels getting the power, two at rear and one at front. Only slight issue is that the rear viscous lock is broken since the seal has leaked and the silicone oils and diff oils have mixed. But that I will fix some day later…
But now back to the topic and opening the IB5 gearbox. I found this nice instruction after some Googling:
And I started to follow it and opened the rear section (5th gear housing):
To get that left gear out I needed to build a special puller tool since I did not had one for this purpose. After I removed the 5th gear gears, selector and the housing it looked like this:
The next task was to remove the actual gearbox casing:
And after I removed input & output shafts, 1-4 gear selector and the diff it looked like this:
Next task is to weld the diff:
But unfortunately I did not had anymore time to continue work today so this will continue later…
I needed to open IB5 gearbox taken out from Ford Ka. After opening the rear section and removing a couple of parts I noticed that I cannot go any further without a proper puller tool. Unfortunately I did not had one for this need, but fortunately this wasn’t the first time such issue occurs. 😉
So I started to create a puller tool for the fifth gear:
I started with cutting a fork from stainless steel since it is a little bit stiffer than regular steel. Regular steel would probably have worked as well, so it was a bit overkill to use stainless steel I believe.
Here is a photo of ready product:
Not that pretty since I did not grind any corners or did any finishing to it. Maybe someday later….
But it worked as expected and now I have IB5 fifth gear puller:
If somebody is creating something similar I recommend using M16x1 thread instead of standard M16x2. I would used that, but I don’t have tooling to create such threw. But even with this coarse threw the tool was able to do its job very nicely.
And just in case you wonder about the standard M threads, here is a rather nice table about those: