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prop too short?
robbydee - 27/5/09 at 08:13 PM

This is a pic of my prop, is it too short not engaging properly? causing too much play?



total prop length is 920mm

diff flange to gearbox casing is 875mm

So is this actually too short?

jacko - 27/5/09 at 08:19 PM

yes it looks it to me mine only has about 20mm / 25mm gap when fitted
Jacko

robbydee - 27/5/09 at 08:24 PM

I have actually broken 1 gearbox casing and replaced a few rear seals so beginnig to think of causes...

blakep82 - 27/5/09 at 08:32 PM

eek, i'm getting worried now, i got my prop made without my gearbox being in the right place... should still stil better than yours though.

i would have thought the worst result would be the splines stripping from the output shaft on the gearbox.

but it could do with a better fit. i recommend dunning and fairbank. they came in a good £50 cheaper than everyone else for my prop

or would it be possible to get a spacer made for the diff end?

[Edited on 27/5/09 by blakep82]

blakep82 - 27/5/09 at 08:43 PM

http://www.locostbuilders.co.uk/viewthread.php?tid=114280

might be worth asking the length?

robbydee - 27/5/09 at 08:47 PM

thats for an english diff though... is that different to the sierra one?

MikeRJ - 27/5/09 at 09:09 PM

quote:
Originally posted by blakep82
i would have thought the worst result would be the splines stripping from the output shaft on the gearbox.


Worst result would be the large imbalance forces caused by the UJ not being adequately supported causing a fatigue fracture and the prop letting go. If the gearbox tail housing has already broken then it's time to get it fixed properly IMO.

blakep82 - 27/5/09 at 09:10 PM

quote:
Originally posted by robbydee
thats for an english diff though... is that different to the sierra one?


i thought they were the same? or is that atlas and sierra that are the same?

owelly - 27/5/09 at 09:14 PM

Just get a 20-30mm spacer for the prop-diff flange.

dave1888 - 27/5/09 at 09:14 PM

How about fitting a spacer between the prop and rear diff. 20mm or so.

robbydee - 27/5/09 at 09:16 PM

anyidea where i can get a spacer?

aerosam - 27/5/09 at 09:22 PM

Any good local engineering workshop should be able to make one for you. As you have the prop removed, take it down and they will use the end of it as a template.

robbydee - 28/5/09 at 09:30 AM

Just ordered a new Bailey Morris Prop....

Should be here Monday, ...

MikeRJ - 28/5/09 at 10:04 AM

quote:
Originally posted by robbydee
Just ordered a new Bailey Morris Prop....

Should be here Monday, ...


That was by far the best solution. A thin spacer on the diff end might be ok, but you are essentially transferring the problem to the other end of the prop.

MikeR - 28/5/09 at 12:08 PM

i'm with the rest - should be about an inch further in the gearbox.