Front Differential Lock casting broken

[heinkeljb]

I discovered whilst doing all the work for the last MOT that I had no front Differential lock. Closer inspection revealed that one of the bit of the aluminium casting that holds the "H" shaped leaver had broken.
As the front differential lock was not a real necessity for the MOT, I left it alone.
Having come back from Holland I could spend some time looking for a replacement casting. Found one and with a little bit of anti rust / penetrating oil / thicker oil made it work correctly.

Dismantling things like the spring meant I had to undo the top mounting bolt as the bottom one would not come undone! Having dismantled things and undoing the nuts holding the casting in place I discovered that two of the studs had sheared (although a long time ago as the broken surfaces were not bright and shiny)!
Took the casting off and found more broken castings. The top two holes of the differential side plate had snapped the top half of the holes and so there were two half moons of casting just held in place by the clamping force of the outer casting!

There was not much that I could do about those bits as it would mean replacing the whole casting and having to deal with the fulcrum pins as well! So I have left that casting weel alone as it was not leaking or anything.

Now I had two broken off studs to deal with. The on the left of the differential lock pin was easy as there was lots of room to get the drill in there and drill the stud out to the correct size just to re-tap it. I decided I wasn't going to bother trying to remove the old broken stud as the possibility of breaking an "easy out" (hardened steel) in the hole would seriously ruin my day!

The second one was more tricky as the clutch tube was directly in the way! So I had to undo the 10mm mountings holding the clutch tube in place. Then as you can see, gently move and hold it out of the way whilst I drilled and re-tapped the right hand side broken stud.
Found two replacement studs and using the two nut trick, wound the studs into place.
Then it was just a question of putting things back together again.

So now the offside is fixed, just an issue with one of the fulcrum pins on the nearside which needs looking at - the rear one is seized and as you can't get a direct line on it. It is very difficult to make the pins move once they have decided to seize! I suppose I will have to dismantle that whole side so I can get the casting off the side of the differential and on to the workbench.

Now I can take Lurch for a drive and see if the leak from the rear offside hub was just a temporary thing or if I will have to pull the hub apart to replace the oil seal and collar.
As per one of my previous posts - The life of Haflinger owner is fraught with difficulties and a never ending stream of repairs!

John

[AustHaflinger]

So you did run over a Chinaman in a previous life - payback is a bitch

Yet despite with all these troubles you have had, you can still drive more often and further than just about any one on the forum. (hopefully my registration rules will change soon so I can drive further than 40km from home).

These side issues are trying but thankfully not stoppers though a rear fulcrum playing up can give you a bad hair day

So you now do have a working front diff lock? Not such an issue for most people (I really use mine even when offroad) but it is nice to know everything works.

Glad to see you are working through the issues.

Garry

[heinkeljb]

In fact other than having to put new King pins (Swivel pins) in when I first bought Lurch, I have had to do very much other than service items until recently when I had the gearbox / rear differential refurbished (twice!). Now this casting and still to do fulcrum pin.

The servicing is / can be just as bad with the amount of different things you have to do at relatively short time intervals. Like I am only a couple of hundred miles off having to do another oil change on the engine after driving to Holland and back!

John