Shortening a jackshaft

mercskeepmeinajob wrote: On a superior rear engined VBUS model they have a real short shaft with the gearbox uni not aligned and leads the diff uni by 18 degrees. Had one shaft returned to Hardy Spicer several times, they didn't understand leading and trailing joints and wouldn't weld it back in the correct position.

Never seen a uni/uni shaft running leading or trailing angles, but it's common practice when you mix CV and universals.
Live axle Commodores had uni/CV/uni tailshaft with the unis set 15 degrees off.
Live axle Falcons tried everything, ever cargo fibre shafts but neither eliminated the "lift off" vibration they all had.
Once rolling along both were fine but taking off they would wind up the diff (crook upper arm configurations) upsetting flange angles > vibration.
Full CV or CV mated to tripod spider seems the norm these days and certainly gives smooth power delivery. As the spline is incorporated, the completed shaft is very neat.

Thanks for all the valuable input, plus the charts etc.
Was round at a blokes place yesterday, I had previously bought an Inter D1300 series gearbox off him which had an 'island' transfer case. Asked if he still had the jackshaft, he told me to stick my head underneath and luckily it was still there. After much swearing and skinning of knuckles plus eyes full of crud, got her off, bought it home and scrubbed her up. One end has the common 1310 Spicer uni yoke, other end doesn't match anything I have here, too long anyway. After a bit of head scratching, back to the Spicer charts and spotted an extremely short male stub with centre of cross to end of spline measurement of 5.188"
Overall should give entire length of just on 8.0" centre of yoke to centre of yoke.
If Spicers chart is accurate (no real reason to doubt it) can install it to a MAXIMUM of 20 degrees, so reckon that as long as I keep the two yoke faces parallel, can get away with just enough inclination angle (around 3 or 4 degrees) for easy instillation.
If I accurately measure the centreline of the existing engine and transmission centres in relation to the chassis, can then build (or adapt) the replacement engine/transmission to the same specs.
Dave

A trick I use to get flanges parallel is use my iPhone as it has a very accurate spirit level built into it that has a digital readout.

I actually have my wife's old iPhone in the garage just for use as a spirit level.

Zuffen. Great idea! I have an iPod 4 here, is it downloaded (spirit level) from the app store? Not brilliant when it comes to mobile phones, (or computers for that matter!)
Thanks, Dave

Worked out how to download that level. How good is that? Now all I have to do is calibrate it against a builders level. No good using a doorway, all out of plumb (Cogzbilt!)

Dave_64 wrote: (Cogzbilt!)

Ha ha! That'd be a good nickname for the Commer.

Jarrod.

Mate of mines daughter does a bit of painting, has offered to paint a Bantam cock(erel) on the front. Don't know how to take that!

Now thereza eye deer
COGZBILT

LOL






A man n hiz machine
or should th@ B
a Man n hiz cogz
LOL

cya

Twin sticks AND twin stacks! Like it!

Swishy man you are good on these puter things
Don't know how you do it but keep em coming