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Exciting stuff this isn't it 
Discovery 1 V8 Cummins 6BT Conversion
- Thread starter Alex458
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So after life getting in the way and having so much other work on I’m now back on the disco project finally!
Bought my own lathe to save having to machine bits after work which has helped!
So transfer box input gear machined, pressed the machined down daf prop flange In and welded up.
It was preheated, welded with high tensile filler and then slow cooled to give it the best chance.
Then as the daf gear was 50mm od and the landrover bearing was 2” I had to sleeve it and machine back to 2” so I could use the standard bearing in the lt230.
Hoping to push on now over the next few weeks and will update when I can!
Bought my own lathe to save having to machine bits after work which has helped!
So transfer box input gear machined, pressed the machined down daf prop flange In and welded up.
It was preheated, welded with high tensile filler and then slow cooled to give it the best chance.
Then as the daf gear was 50mm od and the landrover bearing was 2” I had to sleeve it and machine back to 2” so I could use the standard bearing in the lt230.
Hoping to push on now over the next few weeks and will update when I can!
Loyal discovery
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This is epic, looking forward to more updates!
So after test fitting the input gear I had made it was only engaging the gearbox splines by about 10mm which wasn’t nearly enough and would have failed pretty quickly.
I had miss measured the daf gearbox output shaft and thought it extended further than it did.
So I went back to the drawing board to see what I could do, problem I had was The splined coupling I had machined out of the daf prop flange just wasn’t long enough and as it was very similar in size to the original bearing seat on the lt230 input gear I couldn’t just weld it on the end with any reliable strength.
what I’ve done now is weld the original spud shaft from the V8 auto box into the end of the splined coupling from the daf.
this essentially makes the way it’s joined to the lt230 the same as original autobox.
The surface area of the weld is smaller but I have managed to weld it internally too at the base inside the splines, if it’s strong enough only time will tell but as before it was machined and a tight press fit then pre heated and slow cooled and welded with high tensile filler.
I then cut the original threads off the daf output shaft and drilled and tapped so I could bolt this shaft as it would have been on the standard autobox.
Ordered a new standard input gear from Ashcroft’s and have fitted it all up and everything now fits spot on.
Managed to get the prop lengths measured up so I can now alter those which happens to be 50mm shorter rear and 50mm longer front.
Next up is the gearshift setup, this wouldn’t be a big problem on the defender as the original gearstick location is quite far forward, however with the discovery as the gearsticks are much further back from the bulkhead this meant the gearstick would have ended up where the heater matrix currently is.
After playing with the idea of making a custom linkage up to bring it backwards it was becoming quite an issue to keep it within the space between the top of the tunnel.
By accident one night I came across a triumph herald remote gearlever on eBay which is exactly what I needed to make things work and all I need to do is make an adapter plate to bolt it to the top of the box and then weld the ball off the original selector onto the end of this one
The gearstick ends up in the space the automatic shift used to be.
And as for low box and diff lock I will be using air actuators.
I had miss measured the daf gearbox output shaft and thought it extended further than it did.
So I went back to the drawing board to see what I could do, problem I had was The splined coupling I had machined out of the daf prop flange just wasn’t long enough and as it was very similar in size to the original bearing seat on the lt230 input gear I couldn’t just weld it on the end with any reliable strength.
what I’ve done now is weld the original spud shaft from the V8 auto box into the end of the splined coupling from the daf.
this essentially makes the way it’s joined to the lt230 the same as original autobox.
The surface area of the weld is smaller but I have managed to weld it internally too at the base inside the splines, if it’s strong enough only time will tell but as before it was machined and a tight press fit then pre heated and slow cooled and welded with high tensile filler.
I then cut the original threads off the daf output shaft and drilled and tapped so I could bolt this shaft as it would have been on the standard autobox.
Ordered a new standard input gear from Ashcroft’s and have fitted it all up and everything now fits spot on.
Managed to get the prop lengths measured up so I can now alter those which happens to be 50mm shorter rear and 50mm longer front.
Next up is the gearshift setup, this wouldn’t be a big problem on the defender as the original gearstick location is quite far forward, however with the discovery as the gearsticks are much further back from the bulkhead this meant the gearstick would have ended up where the heater matrix currently is.
After playing with the idea of making a custom linkage up to bring it backwards it was becoming quite an issue to keep it within the space between the top of the tunnel.
By accident one night I came across a triumph herald remote gearlever on eBay which is exactly what I needed to make things work and all I need to do is make an adapter plate to bolt it to the top of the box and then weld the ball off the original selector onto the end of this one
The gearstick ends up in the space the automatic shift used to be.
And as for low box and diff lock I will be using air actuators.
Well due to the current situation I will be spending the majority of my time at home for the foreseeable due to some health issues that wouldn’t agree too well with this virus.
hope everyone else is doing ok.
A friend was due to bring over a clutch slave and air tank this weekend but won’t be happening sadly now for a while
As my workshop is at home I’ve been doing all the bits I can without any more parts.
The gearbox and transfer box are now connected and bolted together and everything seems to spin nicely with no binding etc.
while it was all on the floor I modified the triumph gearshifter and made an adapter plate to bolt this into the box, all seems to work and I can select all the gears fine.
Hopefully get it all back in tomorrow
hope everyone else is doing ok.
A friend was due to bring over a clutch slave and air tank this weekend but won’t be happening sadly now for a while
As my workshop is at home I’ve been doing all the bits I can without any more parts.
The gearbox and transfer box are now connected and bolted together and everything seems to spin nicely with no binding etc.
while it was all on the floor I modified the triumph gearshifter and made an adapter plate to bolt this into the box, all seems to work and I can select all the gears fine.
Hopefully get it all back in tomorrow
Attempted to get the gearbox back in but due to the weight and shear pain in the backside and no one able to come and give me a hand due to the current situation I went to plan B
this was take the engine back out bolt gearbox on and put it all in as one with a telehandler!
I also took the opportunity to do a few jobs while it was out, modified the lower coolant outlet so it no longer pointed down and reduced it’s size.
Fitted a new diesel lift pump as the hand primer was stuffed on the old one and machined an adapter to fully plump in my aeroquip AN10 turbo oil drain into the block.
Eveything is now bolted in, now onto the propshafts finally and then plumbing/wiring etc
this was take the engine back out bolt gearbox on and put it all in as one with a telehandler!
I also took the opportunity to do a few jobs while it was out, modified the lower coolant outlet so it no longer pointed down and reduced it’s size.
Fitted a new diesel lift pump as the hand primer was stuffed on the old one and machined an adapter to fully plump in my aeroquip AN10 turbo oil drain into the block.
Eveything is now bolted in, now onto the propshafts finally and then plumbing/wiring etc
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Attempted to get the gearbox back in but due to the weight and shear pain in the backside and no one able to come and give me a hand due to the current situation I went to plan B
this was take the engine back out bolt gearbox on and put it all in as one with a telehandler!
I also took the opportunity to do a few jobs while it was out, modified the lower coolant outlet so it no longer pointed down and reduced it’s size.
Fitted a new diesel lift pump as the hand primer was stuffed on the old one and machined an adapter to fully plump in my aeroquip AN10 turbo oil drain into the block.
View attachment 204227
View attachment 204228
Looking good well done matey.
Eveything is now bolted in, now onto the propshafts finally and then plumbing/wiring etc
Zed.
Well-Known Member
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- Deepest Bandit country (Wales)
what are you doing about brake-servo vacuum? the td5 alternator seems to be the 'go-to' on cummins swaps?
Rich.
Rich.
Thanks kevstar, I seem to be over the biggest challenges now hopefully!
And rich, I think an alternator with vacuum pump is the way I will go. I was tempted to go with a hydro boost brake servo which runs off the power steering circuit but this is quite expensive.
Been pondering it for a while because I want to retain the 24v starter motor as it spins the engine so much better than 12v.
I think the plan now is 12v alternator with vac pump, 2 batteries and a series parallel start relay.
And rich, I think an alternator with vacuum pump is the way I will go. I was tempted to go with a hydro boost brake servo which runs off the power steering circuit but this is quite expensive.
Been pondering it for a while because I want to retain the 24v starter motor as it spins the engine so much better than 12v.
I think the plan now is 12v alternator with vac pump, 2 batteries and a series parallel start relay.
Right got some more bits done,
I’ve now fitted a disco 2 alternator with vacuum pump, had to make a custom mount up and waiting on some fittings so I can plumb the oil feed in
Power steering is all plumbed in now, I’m aware the pressure is quite a bit higher with the daf pump but will just have to be careful for now and fettle the relief valve when im back at work.
All radiator pipes are made and heater matrix is plumbed in, managed to squeeze the original V8 radiator in.
Also got the throttle cable connected which was the easiest bit as the original V8 one is plenty long enough and even the Clevis and pin fit the arm on the pump just needed a quick bracket making.
And finally Changed the stop solenoid in the diesel pump for a 12v version.
Suppose I better tackle the wiring soon, hoping it won’t be too bad as the electrics on the 6bt are minimal and hoping to use some sensors off the V8 so the temp gauge works etc
I’ve now fitted a disco 2 alternator with vacuum pump, had to make a custom mount up and waiting on some fittings so I can plumb the oil feed in
Power steering is all plumbed in now, I’m aware the pressure is quite a bit higher with the daf pump but will just have to be careful for now and fettle the relief valve when im back at work.
All radiator pipes are made and heater matrix is plumbed in, managed to squeeze the original V8 radiator in.
Also got the throttle cable connected which was the easiest bit as the original V8 one is plenty long enough and even the Clevis and pin fit the arm on the pump just needed a quick bracket making.
And finally Changed the stop solenoid in the diesel pump for a 12v version.
Suppose I better tackle the wiring soon, hoping it won’t be too bad as the electrics on the 6bt are minimal and hoping to use some sensors off the V8 so the temp gauge works etc
Decided to have a go at tackling the wiring, which to be honest wasn’t all that bad.
stripped out all the injection related wiring and all I kept was oil pressure, temp gauge wire, coil live (used this for the stop solenoid on the diesel pump), and alternator charge light.
Fair bit came out of the engine bay, I then removed the ECU and wired up the engine.
Next up pulled the fuel pump out the tank, removed the pump from the housing and I’m now pulling fuel from what was the original return line as this sits right at the bottom of the housing, then extended the hoses under the bonnet and routed them round the rear of the engine to the lift pump and return lines.
I piped the clutch up using an original landrover clutch master that came with the second hand pedal box I bought however after bleeding it it wasn’t moving enough fluid to disengage the clutch fully.
A friend was due to be bringing me the original master cylinder from the lorry but due to the current situation can’t.
After some research the original lorry one has an inch bore master and the discovery’s one was no where near that so no wonder is wasn’t working.
I managed however to get an inch bore brake master cylinder intended for a series ll and have adapted it to fit and now have a working clutch although is a serious leg workout without the air assist connected! Although with air it can be operated with two fingers.
You can see the bore difference between the cylinders.
Not much left now until I can start giving it a drive round the farm for a bit of a shakedown! (All our land so not breaking any Coronavirus lockdown restrictions)
Sadly due to not having any work at the moment I’m having to conserve funds a little so buying the stainless exhaust parts is out the question at the moment so I’ve made a temporary exhaust just to stop it blowing fumes in the cab and to keep the heat off the bulkhead.
Not planning to keep it even though a very good friend sorts my mots he said I have to have a least one silencer or something that looks like one and it can’t come out the bonnet!
Same situation with not having an intercooler or pipe work at the moment so just straight off the turbo to the intake at the moment.
things left before being able to test drive are,
Front propshaft
Extend gear-lever
Refit center console
Extend steering shaft
Fit some electric cooling fans
Wire up the second battery and start relays
Refit slam panel and bonnet
Get an air filter on
Probably some little jobs I’ve forgotten but certainly exited to hopefully be able to drive it soon! Will try get a video of it too.
stripped out all the injection related wiring and all I kept was oil pressure, temp gauge wire, coil live (used this for the stop solenoid on the diesel pump), and alternator charge light.
Fair bit came out of the engine bay, I then removed the ECU and wired up the engine.
Next up pulled the fuel pump out the tank, removed the pump from the housing and I’m now pulling fuel from what was the original return line as this sits right at the bottom of the housing, then extended the hoses under the bonnet and routed them round the rear of the engine to the lift pump and return lines.
I piped the clutch up using an original landrover clutch master that came with the second hand pedal box I bought however after bleeding it it wasn’t moving enough fluid to disengage the clutch fully.
A friend was due to be bringing me the original master cylinder from the lorry but due to the current situation can’t.
After some research the original lorry one has an inch bore master and the discovery’s one was no where near that so no wonder is wasn’t working.
I managed however to get an inch bore brake master cylinder intended for a series ll and have adapted it to fit and now have a working clutch although is a serious leg workout without the air assist connected! Although with air it can be operated with two fingers.
You can see the bore difference between the cylinders.
Not much left now until I can start giving it a drive round the farm for a bit of a shakedown! (All our land so not breaking any Coronavirus lockdown restrictions)
Sadly due to not having any work at the moment I’m having to conserve funds a little so buying the stainless exhaust parts is out the question at the moment so I’ve made a temporary exhaust just to stop it blowing fumes in the cab and to keep the heat off the bulkhead.
Not planning to keep it even though a very good friend sorts my mots he said I have to have a least one silencer or something that looks like one and it can’t come out the bonnet!
Same situation with not having an intercooler or pipe work at the moment so just straight off the turbo to the intake at the moment.
things left before being able to test drive are,
Front propshaft
Extend gear-lever
Refit center console
Extend steering shaft
Fit some electric cooling fans
Wire up the second battery and start relays
Refit slam panel and bonnet
Get an air filter on
Probably some little jobs I’ve forgotten but certainly exited to hopefully be able to drive it soon! Will try get a video of it too.
Well exiting times I’ve managed a test drive!
Managed to get lots of jobs done although still not finished but getting rather close now.
I’ve got the 24v starter motor working and retained 12v run and charge of 2 batteries.
You can buy a purpose made relay from Bosch to do this but they are blinking expensive and I was sure there must be a way round it, what I needed was 2 high amp 12v double pole double throw relays, easy I thought but I couldn’t find anything over 50a.
What I settled on in the end was 2 500amp winch relays. These are wired up to switch the second 12v battery into series with the one in the original location when I want to start which gives me 24v to just the starter and then when I switch them off after starting it goes back to parallel and will then charge at 12v with the alternator.
Was a bum twitchy moment the first time I tried it, had visions of exploding batteries but it works faultlessly so well chuffed!
Extended the steering shaft by cutting it in the middle machining a boss to fit between the cut ends that also added 30mm to the length and tig welded up.
Fitted a pre made 50mm propshaft spacer to the front prop which sorted that.
Extended and cranked the gearstick to make it easier to reach from the drivers seat, it has quite a long throw that I might look to modify in time but I’m sure I’ll get used to it.
And finally got to go for a test drive round the farm! Everything feels pretty good and it sounds awesome although rather loud with the lack of exhaust or silencers.
A few teething issues cropped up though.
Steering box started leaking out the top under the 4 bolt plate, I’ve today changed the seal in the top and all seems dry again.
im not sure if this is because of the extra pressure or seal perishing due to age lack of oil as it’s been drained for a while, I’ll soon find out I’m sure.
2 oil leaks on the engine one from the turbo return and one from under the right engine mount where the original filler used to be when it was in the lorry. Hopefully will sort these tomorrow, think I may have forgotten to put sealant on the one.
And finally the thermostat was stuck and didn’t open when it got to temperature, replaced it today after testing the old one in a pan of water.
Will get some pics of it outside tomorrow
Managed to get lots of jobs done although still not finished but getting rather close now.
I’ve got the 24v starter motor working and retained 12v run and charge of 2 batteries.
You can buy a purpose made relay from Bosch to do this but they are blinking expensive and I was sure there must be a way round it, what I needed was 2 high amp 12v double pole double throw relays, easy I thought but I couldn’t find anything over 50a.
What I settled on in the end was 2 500amp winch relays. These are wired up to switch the second 12v battery into series with the one in the original location when I want to start which gives me 24v to just the starter and then when I switch them off after starting it goes back to parallel and will then charge at 12v with the alternator.
Was a bum twitchy moment the first time I tried it, had visions of exploding batteries but it works faultlessly so well chuffed!
Extended the steering shaft by cutting it in the middle machining a boss to fit between the cut ends that also added 30mm to the length and tig welded up.
Fitted a pre made 50mm propshaft spacer to the front prop which sorted that.
Extended and cranked the gearstick to make it easier to reach from the drivers seat, it has quite a long throw that I might look to modify in time but I’m sure I’ll get used to it.
And finally got to go for a test drive round the farm! Everything feels pretty good and it sounds awesome although rather loud with the lack of exhaust or silencers.
A few teething issues cropped up though.
Steering box started leaking out the top under the 4 bolt plate, I’ve today changed the seal in the top and all seems dry again.
im not sure if this is because of the extra pressure or seal perishing due to age lack of oil as it’s been drained for a while, I’ll soon find out I’m sure.
2 oil leaks on the engine one from the turbo return and one from under the right engine mount where the original filler used to be when it was in the lorry. Hopefully will sort these tomorrow, think I may have forgotten to put sealant on the one.
And finally the thermostat was stuck and didn’t open when it got to temperature, replaced it today after testing the old one in a pan of water.
Will get some pics of it outside tomorrow
Oil leaks now sorted, got some pics from shortening the rear prop I forgot to put up too I’ll add.
Was surprisingly easy to grind the original weld off the joint to the tube, not much penetration in the original landrover weld to be honest!
Knock the joint out the tube, cut the tube down and reweld keeping the joint orientation the same of course and then balance after.
And now able to give it a good shakedown round the farm, plan to use it for the next week or so just round our land which has some steep hills etc and if nothing rears it’s head and I’ve managed to sort the paperwork with the DVLA (not looking forward to it) it will be on the road!
pic from today on a track at home, it’s pretty steep in places but fair play the Cummins pulls blinkin hard when you show it the loud pedal.
Was surprisingly easy to grind the original weld off the joint to the tube, not much penetration in the original landrover weld to be honest!
Knock the joint out the tube, cut the tube down and reweld keeping the joint orientation the same of course and then balance after.
And now able to give it a good shakedown round the farm, plan to use it for the next week or so just round our land which has some steep hills etc and if nothing rears it’s head and I’ve managed to sort the paperwork with the DVLA (not looking forward to it) it will be on the road!
pic from today on a track at home, it’s pretty steep in places but fair play the Cummins pulls blinkin hard when you show it the loud pedal.
Hicap phill
Well-Known Member
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As for dvla... you have only changed the engine
Body,chassis axles gearbox the same so hopefully no problems.
Body,chassis axles gearbox the same so hopefully no problems.
As for dvla... you have only changed the engine
Body,chassis axles gearbox the same so hopefully no problems.
Just been reading on dvla website and seems all I should need is a receipt for the engine stating fuel type, cc and engine number as that’s all I’ve changed really.
So fingers crossed it should be ok
Spoke to an insurance company who are happy to insure it all mods declared for a very reasonable price too.
Got the 3D printer out today, wanted to blank off where the transfer box lever used to be in the center console.
The start button I was using fell apart so took the opportunity to put a proper one in the blanking plate I printed.
Going to put the switches for the air actuators that will work the low box and CDL where the original gear pattern sticker used to be.
The start button I was using fell apart so took the opportunity to put a proper one in the blanking plate I printed.
Going to put the switches for the air actuators that will work the low box and CDL where the original gear pattern sticker used to be.
Well it would appear I wasn’t careful enough with not holding on full lock.. and I split the steering box!
I have now put a relief valve in the system and replaced the steering box, should have done it in the first place to be honest!
Finally got the stainless exhaust in and started making it.
Had a load of these laser cut to make the bends as preformed bends are quite expensive and I wasn’t sure how I was going to route the exhaust until I started making it.
Got the downpipe done and ran out of argon!
I have now put a relief valve in the system and replaced the steering box, should have done it in the first place to be honest!
Finally got the stainless exhaust in and started making it.
Had a load of these laser cut to make the bends as preformed bends are quite expensive and I wasn’t sure how I was going to route the exhaust until I started making it.
Got the downpipe done and ran out of argon!
