how to balance tailshaft??

[Haydz]

hey guys. i think i have a problem with my tailshaft.


i think it might be out of whack or something wrong with it.


what happened was. i took the sedan rear half and manual front half. and put them together.

in no special way.


is there a certain way to re allign them or something like that.


also the symptoms are like a vibration in certain parts of the rev range like constantly there

any input/suggestions welcome. thanks alot

[greenacc]

all you can do at home is unbolt the 2 halfs again, turn one piece by say 180 degrees, or 1 bolt hole if u like, and bolt it up again. You could try as many different positions as there are bolt holes if your keen. You should find that some positions are better or worse than others, and might even get it perfect if your lucky. Otherwise take it to a transmission place or someone who can balance it properly.... not sure who ?

[PREDATR]

Take it to hardy spicer and get them to check the balance...

[Haydz]

will they charge alot to balance it properly?

as i dont want to pay too much when i can go get another from the wreckers.

or something.

[PREDATR]

I reckon its around 220.

[Haydz]

**** that id rather have it a bit wonky. or buy another one allready balanced.

[keza87]

A reconditioned tail shaft for my auto VN cost about $300!

[immortality]

driveshafts are normally assembled with the universals on the ends of each half shaft in alignment. so there are only really 2 ways that it could bolt together for optimum ballance. if still not right after trying that then try with the universals out 90degrees. again there are only 2 possible positions. if that doesn't work then the only way is to have it ballanced profesionally. i have pieced together different driveshafts before and not had ballance issues as long as you maintained the original alignment of the universals

[Haydz]

ok guys.

i will pull mine out and get some pictures. and from there can you tell me if they are in correctly?

[moff_man]

i got a shaft shortned and ballanced for a vl project i was doing at shepparton super ballance (nth vic)and cost me $110 including fright!!!!!

and yes i think the shaft is out grab some pics and well shall see where you went wrong and guide you in the right derection young grass hopper

[Haydz]

hey guys.


i got under and had a look.



the weights on the gearbox side are a few mm different to the first set of weights on the sedan tail shaft and the rear weights are directly opposite the front ones. on the rear half/

hope that makes sense

[immortality]

don't look at the weights, they were put there when it was ballanced. what you need to check is the orientation of the front universal in relation to the rear universal

[Haydz]

so theyre all not balanced the same?

say if i were to look at the same ones of a manual vn

ill go get a picture

[Haydz]

REAR




FRONT




without moving the car at all and picture was taken from drivers side




im really kinda stuck as to get it balanced its going to cost me 180 dollars.

or 120 for a second hand one from commwreck

[immortality]

remove the 6 bolts from the CV joint and rotate the rear half 90degrees and see if that effects the ballance.

if you look at the rear picture, you can see the universal joint (through the driveshaft) is horizontal, if you then look at the front picture the univeral through the driveshaft is vertical. they should both be the same way

[Pub247]

Geez $180 is a bit steep unless they planned on replacing stuff aswell. My mate got one shortened and balanced for $150

[Haydz]

thanks immortaltiy


so take it apart from the cv joint and make both the joins as close as possible?

[Cheap6]

remove the 6 bolts from the CV joint and rotate the rear half 90degrees and see if that effects the ballance.

if you look at the rear picture, you can see the universal joint (through the driveshaft) is horizontal, if you then look at the front picture the univeral through the driveshaft is vertical. they should both be the same way

With a one piece tailshaft (and with the diff. pinion and extension housing flanges parallel) that would be correct (to line up the uni's) but not if it's the standard Commodore two piece unit.

The centre CV joint and centre bearing combo. alters the angle of the front and rear uni's relative to each other. To correct for that the front and rear uni's are meant to have a radial offset relative to each other i.e. the front and rear uni's are "clocked".

I don't know what the angles are off the top of my head and wagon, with a longer wheelbase, will probably be different to sedan. The spec. will be in the relevant factory workshop manual if someone has access to one and will post it up. Otherwise checking on another car(s), perhaps in a wrecking yard might be one option. I may have the numbers somewhere and if I find them I will post them up.

Tailshaft balance (as distinct from alignment) is a separate issue.

[Haydz]

ok mate well what is my best option


i have three

1. get my tailshaft balanced for the cost of 180

2. buy a new tailshaft for 120

3. or i can get a known good tailshaft from an auto and take note of how the front piece was installed and swap it for the manual front half.

im opting for option 3 as it will cost me nothing

[rcnugget]

I would have a go at rotating one of the yokes 180 degrees as it is not correct how it is sitting at the moment, whenever I used to make shafts when I was engine reconditioning the yokes should always line up and not 90 deg offset like yours are but I did not see many factory ones...

personally I would just pay someone to balance it then you know 100% that it will be correct and you will have no further problems

[greenacc]

As Nugget said, you have 4 options. Number 4 is the time consuming one where you take the shaft out and turn it a bit and put it back in until you try all the combinations of orientations and bolt holes until you find one you are happy with. At least if you do that you will either get it right for free, OR, you know you have tried everything and know you need to get it balanced profesionally. that way your not spending money if you don't need to.

[immortality]

With a one piece tailshaft (and with the diff. pinion and extension housing flanges parallel) that would be correct (to line up the uni's) but not if it's the standard Commodore two piece unit.

The centre CV joint and centre bearing combo. alters the angle of the front and rear uni's relative to each other. To correct for that the front and rear uni's are meant to have a radial offset relative to each other i.e. the front and rear uni's are "clocked".

I don't know what the angles are off the top of my head and wagon, with a longer wheelbase, will probably be different to sedan. The spec. will be in the relevant factory workshop manual if someone has access to one and will post it up. Otherwise checking on another car(s), perhaps in a wrecking yard might be one option. I may have the numbers somewhere and if I find them I will post them up.

Tailshaft balance (as distinct from alignment) is a separate issue.

mate, i've suggested he puts it as it is would have been originally. i have a spare driveshaft laying in the garage with the universals lined up as i have suggested. came out a VN manual.

[Haydz]

does it work well? or does it have weird vibrations immortality?

[immortality]

i just stuck my head under my VN and the universals are alligned as i've suggested. as far as i'm aware this driveshaft has never been split from factory (i'm only the 2nd owner from 65xxxkm's on the clock).

although the universals do look to be alligned properly, they are infact a few degrees out from each other. however you can only put the 2 halves together in 6 different positions (as there are 6 bolts holding the halves together unless you also remove the CV from the splined shaft). there are 2 postions that are most likely with the universals aligned. if those 2 positions don't work then you can also try it with the universals 90degrees out (seeing as that is how you currently have it, it's obviously wrong for you)

[Haydz]

sweet thanks a heap man