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Scott R



Member Since: 21 Jan 2016
Location: Northampton
Posts: 25

England 1985 Defender 90 Other HT Nato Green
R380 stubby gearbox conversion.

Anyone else building or built one as I'm struggling with the front cover/plate. The original R380 hasn't got the guide tube for release bearing and the Lt77 one isn't thick enough for the bearings to sit in. Ashcroft's website shows a picture of a thin Lt77 with a guide tube welded on so is confusing me.

Post #686174 12th Feb 2018 8:42pm
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Defendermatt



Member Since: 15 Sep 2016
Location: Derbyshire
Posts: 126

United Kingdom 1989 Defender 90 200 Tdi SW Bonatti Grey

You need the conversion part from Ashcroft

http://www.ashcroft-transmissions.co.uk/di...using.html

Post #686257 13th Feb 2018 6:52am
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Scott R



Member Since: 21 Jan 2016
Location: Northampton
Posts: 25

England 1985 Defender 90 Other HT Nato Green

Thanks for the reply and I have seen that but it still doesn’t answer my question. The input shaft bearing on the R380 gearbox needs to stick out the gearbox casing by 14mm, the layshaft bearing approx 5.5mm. The LT77 front cover is 8mm thick so won’t be able to be machined to 14mm deep. The picture on Ashcrofts website doesn’t look like it is going to be thick enough unless there is something I’m missing? And with the lug each side tells me that’s the LT77 cover as the R380 only has a lug one side. Perhaps I just need to go there and look at the item and buy it if it looks right.

This is the difference of thickness between the LT77 and R380 front covers.



Click image to enlarge

Post #686289 13th Feb 2018 9:48am
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Defendermatt



Member Since: 15 Sep 2016
Location: Derbyshire
Posts: 126

United Kingdom 1989 Defender 90 200 Tdi SW Bonatti Grey

The Ashcroft one is correct.
It is not an Lt77 type it is a new machined plate with a guide tube welded on. It is thicker than what you have pictured from what I remember.

Post #686299 13th Feb 2018 10:27am
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Scott R



Member Since: 21 Jan 2016
Location: Northampton
Posts: 25

England 1985 Defender 90 Other HT Nato Green

Thank you for that, deceptive picture from Ashcroft then.

Post #686337 13th Feb 2018 2:05pm
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Defendermatt



Member Since: 15 Sep 2016
Location: Derbyshire
Posts: 126

United Kingdom 1989 Defender 90 200 Tdi SW Bonatti Grey

I think it does look quite slim on Ashcroft's website, but I assure you it is correct - I have used the list of Ashcroft parts for 2 boxes now.

I'd recommend fitting a new input shaft bearing as the old is difficult to remove from the original R380 shaft.

Post #686347 13th Feb 2018 2:55pm
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Scott R



Member Since: 21 Jan 2016
Location: Northampton
Posts: 25

England 1985 Defender 90 Other HT Nato Green

An update. I couldn’t justify the £67+vat for the front cover so went for plan b, machine the LT77 one out to accept the input bearing to a depth equal to the difference in hieght between the two bearings then make a spacer the correct thickness equal to how much the layshaft bearing sticks out so it butts upto the cover. Only problem is that when I did machine it the depth way more than the thickness so that was a no go.
So plan c, use the original r380 and attach a guide tube to it.

First was to cut the one off the now scrap Lt77 cover, as you’ll see in the picture you can see where I machined the back out and broke through making it scrap.



Click image to enlarge


I then machined the hole out to clean it up up being that but was still rough cast and then put a screw thread in of no particular size.



Click image to enlarge


Next was to machine the guide tube and thread the end leaving a small step to match the cover.



Click image to enlarge


Which then just screw the two together.



Click image to enlarge


Not sure whether to just use thread lock or to weld it? Just need to mock it up and make sure it’ll work and that the tube isn’t too long or the release bearing will go back far enough after engaging the clutch. Total cost is 20 minutes of my time.

Post #687315 17th Feb 2018 11:58pm
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dorsetsmith



Member Since: 30 Oct 2011
Location: dorset
Posts: 2503

United Kingdom 2003 Defender 90 Td5 HT Caledonian Blue

thread lock not weld pickup 90 TD5 2006

HT 90 TD5 2003

Post #687339 18th Feb 2018 9:02am
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Defendermatt



Member Since: 15 Sep 2016
Location: Derbyshire
Posts: 126

United Kingdom 1989 Defender 90 200 Tdi SW Bonatti Grey

Very neat! Although I think I would weld it for peace of mind

Post #687518 19th Feb 2018 7:25am
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