Converting Type1 IRS to swing axle
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saggs
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Converting Type1 IRS to swing axle
I'm looking to do a type4 conversion into my 67 westy. I was told you can convert the 71 and 72 Irs tranny back to swing axle. Does anyone know if this can be done to a 70 irs trans as well? I guess I'd have to change the throw out bearing and shaft as well if this is possible?
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Marc
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Any dual-sidecover 4-speed IRS Type I/III trans can be converted to swingaxle with the appropriate differential carrier and sideplates.
If you wish to run a late-style clutch cover & release bearing (and I encourage you to do so) the `71/early`72 part will fit a `69 or `70 trans but only the `70 trans case has the three bosses in the casting which you can drill & tap to install a guide tube for the late-style release bearing. There's also an aftermarket tube available that plugs into the input shaft seal bore; I haven't used one of these personally but from all reports they work.
http://aircooled.net/new-bin/viewproduc ... 0721153639
If you wish to run a late-style clutch cover & release bearing (and I encourage you to do so) the `71/early`72 part will fit a `69 or `70 trans but only the `70 trans case has the three bosses in the casting which you can drill & tap to install a guide tube for the late-style release bearing. There's also an aftermarket tube available that plugs into the input shaft seal bore; I haven't used one of these personally but from all reports they work.
http://aircooled.net/new-bin/viewproduc ... 0721153639
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saggs
- Posts: 216
- Joined: Thu Jan 25, 2007 11:47 am
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Marc
- Moderator
- Posts: 23741
- Joined: Thu May 23, 2002 12:01 am
Your `67 II trans should have the 8-bolt differential carrier needed (the ring gear from the IRS trans has to be swapped onto it) and O-ring sideplates that'll fit the IRS trans. The only other parts you will (probably) need are some swingaxle diff-carrier bearing shims so you can get the preload & backlash set right...frankly I think you should leave this to someone with the right tools and experience with the job - the Bentley manual covers the procedure, but without the right $$$ tools and an assortment of shims handy it's really not something you should tackle yourself.
If you'll be using the same clutch cover as you have with the `67 trans, there's no need to alter the `70...but if you want to update to the more robust late setup it can be done by changing the cross-shaft to the `71/early`72 part.
The `70 trans case can be drilled & tapped to accept 7x1.0mm studs (or bolts) to secure the TOB guide sleeve without any disassembly. Of course you don't want to drill too deep and go through, I'll get you a measurement of the stock hole depth this weekend. Late trans cases had an internal step to prevent the mainshaft seal from going in too far, but early ones relied instead upon a flange on the seal. If someone has replaced the seal with the early flanged style it'll have to be changed to the late style before you can bolt down the sleeve.
The other option is to simply buy the aftermarket adapter sleeve & seal deal that plugs into the input shaft seal bore - if you had a `69 trans that would be the only way, but since the `70 case already has the three bosses for the studs/bolts I'd personally consider it more elegant to do the drilling & tapping to fit the stock sleeve.
If you'll be using the same clutch cover as you have with the `67 trans, there's no need to alter the `70...but if you want to update to the more robust late setup it can be done by changing the cross-shaft to the `71/early`72 part.
The `70 trans case can be drilled & tapped to accept 7x1.0mm studs (or bolts) to secure the TOB guide sleeve without any disassembly. Of course you don't want to drill too deep and go through, I'll get you a measurement of the stock hole depth this weekend. Late trans cases had an internal step to prevent the mainshaft seal from going in too far, but early ones relied instead upon a flange on the seal. If someone has replaced the seal with the early flanged style it'll have to be changed to the late style before you can bolt down the sleeve.
The other option is to simply buy the aftermarket adapter sleeve & seal deal that plugs into the input shaft seal bore - if you had a `69 trans that would be the only way, but since the `70 case already has the three bosses for the studs/bolts I'd personally consider it more elegant to do the drilling & tapping to fit the stock sleeve.