Gearbox rebuild

[winterheating]

yep i just stuck a 125tdci onto my piddly little 75ps gearbox ,
i knew about there being a different amount of splines between the lower and higher powered ones, more splines for the stronger boxes. but took a chance

i was planning on changing gearbox but dont have a choice now.
hopefully these 6 speed boxes are robust.

[winterheating]

new box in today



addapted mount to fit mondeo mount.



nearside ready for drive shaft



as you can see offside inner drive shaft is quite different,



the shaft output is in different position also, the bearing clamp and suppoert bracket is needed from mondeo



bolt holes are in block ready





bracket lines up ok



shaft in

[winterheating]

here are some estimated speeds with my mmt6 fitted.

and 215 75 16 tyres

diff ratio 2.85 for 5th and 6th

5th 6th
1000rpm= 34mph 42mph

2000rpm= 68mph 84mph

3000rpm= 102mph 127mph

4000rpm= 136mph 169mph

5000rpm= 170mph 211mph

diffratio 4.071 for 1st,2nd,3rd,4th

1st 2nd 3rd 4th
1000rpm= 7mph 11mph 17mph 25mph

2000rpm= 14mph 23mph 34mph 50mph

3000rpm= 21mph 34mph 51mph 75mph

4000rpm= 27mph 45mph 68mph 100mph

5000rpm= 34mph 57mph 85mph 125mph

[winterheating]

thought id update.

mondeo shafts have different size bearings on the spider so arnt interchangable.

Mondeo box output is different to transit, so have had to bodge a bracket for inner shaft.

also gearbox outputs are different width moneo one is about 70mm wider, so inner shaft has had to be extended.

the pot shaft and inner shaft go into mondeo box as the splines are the same thats the only good thing

the top gearbox mount has had to be adapted, the bottom has had to be made up.

whats left;

i still need to get the pickup for VSS onto shaft somhow.

ineed to get the inner shaft thats been welded balanced.

t

[winterheating]

the Gear linkages need to be joined a bit better, im finding it hard to weld the hard steel to the cable as the cable just burns away

also cos nearside pot joint is closer to wheel, when the van leans to the left i can feel the bearings aginst the inside of pot joint, this is the only thing i cant think of how to get round as the outer shafts are hardend so cant be cut shorter and welded.

[Luke]

you like to mess dont you

what are you trying to weld the cables to did you ever get the gas welding gear sorted and cant you use that and braze them

and the drive shafts might be able to be softened back then machined up- but its diffiuclt without knowing the details of the origanal treatment

[winterheating]

ill get some pics tomorrow of everything thats been done.

what are you trying to weld the cables to did you ever get the gas welding gear sorted and cant you use that and braze them

i tried brazing, couldnt get it to take.

and the drive shafts might be able to be softened back then machined up- but its diffiuclt without knowing the details of the origanal treatment

is that when there put on a lathe at high speed and pushed together which heats them then welds together

[winterheating]

This is the shaft thats been extended 30mm but should of been 50mm so i had to space the cv joint inover 20mm .
hopefully i will be able to find somewhere that will balance it for me.#

this is top engine/gearbox mount, the 4 bolt mondeo mount cut, and the black transit mount cut with a bolt going from the back of the mondeo mount, through the threaded hole allready in black transit mount and a nut holding all together at the top. all measured and cut to give correct front back position and height.
allthough looking at that pic it needs abit of a grind to sit flush.





the bottom engine mount altered, the 6 speed box is quite close to the engine bed compared with the 5 speed.
it needs some more structural supports as its moved it allready
the square plate is exactly below old brackets on engine bed so used the 4 captive nuts, the mount has basically just dropped about 45mm, then other end connected to box, with another adapter plate.

[Luke]

and the drive shafts might be able to be softened back then machined up- but its diffiuclt without knowing the details of the origanal treatment

is that when there put on a lathe at high speed and pushed together which heats them then welds together [/quote]no thats friction welding - i dont think they have had that - basically the drive shaft would be a solid bar have all the splines machined on then the the shaft go through a heat treatment process to harden it up it's possable if you know the properties of the metal to soften it off, re machine it then harden it back up again

[Luke]

how close is that bracket to the floor

[winterheating]

this is one end of cable that ive welded but the weak wire has given up.


this is the standard transit gear linkage cable, the gaps of the spirel wire are bigger on a new cable, thats what happens to them they squash not stretch. inside that is wire like bike cable wire, then right in the core looks like a single small rod/wire.



the weld is strong but just leaves a weak part where the cable joins it.
you caqn see how the ends are just crimped on the standard cable


today i have made a tube over the cable and braized inside the tube so the cable is solid, and hopefully i will be able to weld this bit to the other welded rod above


all this is just to get an idea and hopefully will be able to get everything fabricated uplike a proper job.

the trouble is ive tried asking alsortys of engineers and fabricators but people are just ignorant say you cant do this you cant do that and just dont want to nknow.

[winterheating]

how close is that bracket to the floor

errrm i was thinking that aswell for the MOT. it doesnt look to good does it. do think it will fail

my tools, materials and knowledge are limited so ive just boged together what i can

like i say hopefully it will all be done proper.

[coconut]

Could you join the cables by making a 'chocolate block' sort of thing (dont know the correct name, the electrical things in plastic with 2 screws in them) but make it bigger/longer and have grub screws to clamp onto the cable at each end

[Luke]

the trouble is ive tried asking alsortys of engineers and fabricators but people are just ignorant say you cant do this you cant do that and just dont want to nknow.

this is the problem with Britain today it's hard to find decent engineers - they are a dying breed

re. the cable could you weld an eye to the metal and have a cable made up with an eye on each end then bolt it on if so i can give you the number of a place that will make you the cable for i'd guess less than a tenner

[coconut]

Will that mount go up so the top holes of the mount fit the bottom holes of the subframe and then make a smaller plate for the lower holes of the mount

or

could you use a connect/focus sort of set-up instead (is there enough room)