Save up to 15% with Adrian Flux insurance!

Technical Problem with transmition, please help

Currently reading:
Technical Problem with transmition, please help

So i put everything back together by the book, correct nut torque etc. I've done 20 kilometers and now wheel has a play!! Looks that i have to tight it more.:bang: This for the r/h wheel which as i said before axle is bend anyway so i have to replace it.
As for the L/h after i repair the damaged thread i was king of gentle with the torque and it also has a play. Not very happy with the results but i will be back after i order a new shaft.(n)

Thomas
 
gordinir8 said:
As for the L/h after i repair the damaged thread i was king of gentle with the torque and it also has a play.
Click to expand...
With the level of tightening this setup requires I think that you have to go to full torque or it will not work. With any misalignment such as your slight bend in the axle, when you get the right torque there will be a tightness to the bearing.
You can go really tight when everything is right, because until it collapses too much, that spacer is taking all of the tension and only a tiny part of it is applied to the bearing.
You are very hard on yourself Thomas. I bet a lot of 500's have some play like that and are happily driving the road (or sitting sadly in garages:rolleyes:}.
 
fiat500 said:
You are very hard on yourself Thomas. I bet a lot of 500's have some play like that and are happily driving the road (or sitting sadly in garages:rolleyes:}.
Click to expand...

Ignorance is bliss...sometimes. Previous owner was really happy with the car because he had no idea about what was going with his car state. How about short brake hoses that where stretched because of rear swing arm travel and hose brackets where bend!!
The thing is that i don't trust those new spacers available as i believe they require lot of torque, i don't feel happy pulling with a meter long crash bar, something might brake there.
 
gordinir8 said:
, i don't feel happy pulling with a meter long crash bar, something might brake there.
Click to expand...

It won't.:D
All the torque is transmitted through the static centre races of the bearings and the spacer. Until the very final moment when the spacer starts to collapse there is no tightening of the bearings. Sensing when you are getting to that point is the skill....you definitely have that!
When the turning resistance is achieved, the two bearings and the spacer act as one large bearing component and the setup is almost indestructible and can take a huge amount of strain.
It is a superior arrangement to the simple front bearings.
 
Well I worry about the thread not the bearings, I already damaged one thread which of course wasn't intact from the biggining, it was worn before.
 
Hi, I am sure you don't tighten the nut to a torque, you tighten until you achieve a rolling torque of 4.3 lb inch. This is done by fitting the the brake drum and then fitting special tool to the drum I.e. You crush the distance piece until you get some resistance when turning the brake drum, this resistance should be equal to the rolling torque. I had to do this job in a field in Italy, I had to use a 1m long bar on the axle nut and a bar trapped between two wheel bolts, to give enough purchase to crush the distance piece. I tightened until I felt the resistance similar to the front wheel bearings. Fortunately I had a nyloc nut and didn't have to fiddle with a split pin to secure the nut. This was back in 2007 and it is still OK. Forgot to say, I had to dress the stub axle threads with a thread file as they had been damaged when the wheel and axle decided to part company at about 55mph on the motorway.

Ralph
 
Last edited:
Thomas,

One possible solution, given that you can use a lathe, might be to make up a solid, fixed length spacer i.e. no waisted/collapsible section.

You might copy the length of the old collapsed spacer if the same bearings,shaft etc are being used and the preload was correct. For further adjustment, either machine a little more from this new spacer or add some shim washers as appropriate.

This would avoid having to apply a lot of torque to dodgy/worn threads.
It also allows subsequent dismantling/easy reasssembly e.g. seal replacement.

I've seen this done on rear axle pinion shaft collapsible spacers on competition vehicles but the reason may have been to avoid further collapse of the spacer under heavy load causing loss of bearing preload leading to failure.

Or increase the depth of the waisted section on a new spacer to allow it to collapse with less torque applied?

I wonder if it would be possible to convert to 2 ball race bearings or one roller bearing + one ball race or maybe even one of the preset double row bearing units as used on modern front wheel drive cars?

Al.
 
Am I have already reduce the thickness of the spacer on a lathe as Damian suggested me to make it easyer to collapse but as I said I am afraid the damaged/repaired thread, I will disassembly it and see how it is so I can proceed. Also I will use fiat 126 nuts since you don't have to mess with cotter pins etc, I just have to make a groove on the shaft.
 
It's correct that you aren't measuring torque but are checking the rolling resistance of the bearing assembly.
But in my experience, it does take a massive amount of torque to compress the spacer. I am sure that this is all because of modern components not being to the original spec. and not a basic design fault.
 
I agree with Peter, I had to effectively lock the axle using two wheel studs, a length of bat and use a 1 m extension on the socket to collapse the distance piece, and it took a lot of effort there were two of us at it. This, I wouldn't think would happen in the Fiat garage back in the day. If you look in the manuals to see how it is done the Fiat tool to measure rolling resistance is not man enough to cope with the torque required to compress todays aftermarket spacers. machining the central collapsing section a bit more may be the answer. Hope you get it back together soon.

Ralph
 
Ok this tends to be an odyssey. As I mention in a previous post my r/h axle is bend or at list that's what I thought.
I removed it again to see that it is not bend but perfectly straight, problem comes with the outer (close to drum flange) bearing and it's seat which is thicker resulting in a floating bearing when this is in please and tight. You can see at the picture that the bearing seat has less diameter than the rest of the shaft.
Am I missing something here?
Just asking before I order two new shafts
Thomas
 

Attachments

  • 20170211_101819.jpg
    20170211_101819.jpg
    2.2 MB · Views: 59
Looks to me that someone has machined that axle and its not right. The diameter at both ends should be slightly larger than the middle bit so the bearing races become a press fit. Yours has the ends with a smaller diameter. I know they are expensive Thomas but I think you need new axles!
 
Damian i took a closer look and shafts are worn under the race seats, don't ask me how but diameter is reduced and bearing is very loose, it has about 1 mm play!! The other axle at the same part is reworked by a machine shop and i was wondering why!!:confused:
I wonder how i didn't notice that at first place but i remember that bearing had no play before i remove it, probably it was stuck. Anyway i can also get it to a machine shop and repair it but i will go for a pair of new made by VEMA, a fiat aftermarket company. I will report back when i get the parts next week.

Thomas
 
So new shafts are here and already installed. I’ve done the preload procedure on my vice and I have to say that I use an extension, applied a great force but it gave me a feeling that it came to a point which two things could happen. Deform the spacer and everything is good or damage the thread!!(n) Believe me I have experience of torque values around 3000-4000 in/lb using a meter long torque wrench and I have seen top quality sockets and extensions braking easy. But here I was not confident about the axle thread and I think they are not design to withstand such a great torque . I think it has to do with the spacer itself which looks stronger that it should be.
After I pushed it to the limits I removed the nut and try to put a new unused nut and it was going hard meaning that the thread had some kind of deformation.
So I had a plan B, I reduced spacer length using my little trusty lathe, a tenth at a time until I managed to get the desired result. Car runs ok except a brake shoe problem that rubs the drum but I am working on it also.
I would like to thank each one of you for your support.:)
Thomas
 

Attachments

  • 20170217_204756.jpg
    20170217_204756.jpg
    2.6 MB · Views: 62
  • 20170218_142315.jpg
    20170218_142315.jpg
    3 MB · Views: 59
Last edited:
You must log in or register to reply here.

Similar threads

S
  • Question
Technical Problem with slow starter...
Replies
13
Views
505
Suechap1969
S
P
Technical Need help with engine issues
2
Replies
24
Views
2K
fiat500
fiat500
R
Technical Help With Transmission Leak
Replies
8
Views
789
RobertM
R
J
Technical Different ignition, same problem.
Replies
3
Views
95
the hobbler
T
Sleek Lemur
Technical Clutch problems 1972 500R with synchro box
Replies
9
Views
590
Sleek Lemur
Sleek Lemur
Back
Top