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steveH1
17-11-2011, 03:38 PM
Hi,
I've been running a [2nd hand] B44 weekly for approx 5months and think it might be time for the diff balls/washers to be replaced soon. I have recently heard that sometimes B44 diffs may also require some ?extra shimming with wear, over time.
I'm looking for any advise about this if possible.
Thanks

MiCk B.
17-11-2011, 03:47 PM
Hi,

Your correct about the shimming. But it is extra shims between the bearings and the diff outdrives.

With everything assembled, IE as it is now. See if you can move the diff left to right in the gearbox. (So changing the mesh between the two bevelled gears.)
You don't want any movement here. So if there is movement,when you are rebuild add an extra shim between the bearing and the outdrive, to that you push the two gears together.

MiCk B. :-)

steveH1
17-11-2011, 05:01 PM
@MiCk B
Thankyou:thumbsup:

budfish
17-11-2011, 05:13 PM
Hi,
I've been running a [2nd hand] B44 weekly for approx 5months and think it might be time for the diff balls/washers to be replaced soon. I have recently heard that sometimes B44 diffs may also require some ?extra shimming with wear, over time.
I'm looking for any advise about this if possible.
Thanks

New plates,gears and balls start a fresh( obviously buds balls ceramic diff balls )

Steven Forster
17-11-2011, 11:30 PM
New plates,gears and balls start a fresh( obviously buds balls ceramic diff balls )

you got the part numbers for plates and gears ?

how much are your diff balls ?

cheers :thumbsup:

steveH1
17-11-2011, 11:30 PM
@budfish. Yep - I'm planning on using the buds balls - Thanks

jaffacake
18-11-2011, 06:48 AM
Hi,

Your correct about the shimming. But it is extra shims between the bearings and the diff outdrives.

With everything assembled, IE as it is now. See if you can move the diff left to right in the gearbox. (So changing the mesh between the two bevelled gears.)
You don't want any movement here. So if there is movement,when you are rebuild add an extra shim between the bearing and the outdrive, to that you push the two gears together.

MiCk B. :-)
Important not to lock the two plastic gears together though,ideally you want a tiny bit of float between the two plastic gears.

steveH1
18-11-2011, 11:37 AM
@jaffacake
O.K thanks m8 , think I understand so try to minimise left - right movement but not to the point of jamming the diff gear to the input gear.

Hog
18-11-2011, 11:43 AM
While we're on the subject of B44 diff rebuilding - is it possible for the thrust race spring to lose tension over time? Just that with the B44 I'm preparing for the coming season I seem to be having trouble setting the diff so that it doesn't slip but isn't too tight when you turn the wheels.

I've fitted new plates and balls (thrust and main) but there seems to be little adjustment from slipping to too tight.

MiCk B.
18-11-2011, 12:02 PM
While we're on the subject of B44 diff rebuilding - is it possible for the thrust race spring to lose tension over time?......

Yes.

That spring is always under pressure in the diff. So it will not last for ever.

MiCk B. :-)

budfish
18-11-2011, 04:00 PM
While we're on the subject of B44 diff rebuilding - is it possible for the thrust race spring to lose tension over time? Just that with the B44 I'm preparing for the coming season I seem to be having trouble setting the diff so that it doesn't slip but isn't too tight when you turn the wheels.

I've fitted new plates and balls (thrust and main) but there seems to be little adjustment from slipping to too tight.

Good idea to replace the diff screw and nut from time to time

Buds

Hog
18-11-2011, 04:20 PM
Diff screw is in good condition, and I always coat the thread of the screw where it goes into the nut with threadlock and let it dry before re-assembly so I get a good tight fit.


Oooh matron. :p

Steven Forster
19-12-2011, 12:52 PM
Is the part number as3911 for the diff shims and are they for 1 diff or both ???

cheers :thumbsup:

Andyp
19-12-2011, 01:53 PM
Is the part number as3911 for the diff shims and are they for 1 diff or both ???

cheers :thumbsup:

Hey Steve, thats the part you need, long while since i shimmed a b44 diff, but it all depends on how many you need to how many packs you need. im sure you already have some sims in there already so would say you will be safe just to buy one pack

Kept meaning to mention to you that your diff/diffs were clicking last night , was you aware of this ?

Andy

Steven Forster
19-12-2011, 02:42 PM
Hey Steve, thats the part you need, long while since i shimmed a b44 diff, but it all depends on how many you need to how many packs you need. im sure you already have some sims in there already so would say you will be safe just to buy one pack

Kept meaning to mention to you that your diff/diffs were clicking last night , was you aware of this ?

Andy

cheers for that andy, yeah i was aware of the clicking :blush: paul hindson showed me how to check for side play in the diffs and seems like a lot of play there which wont help :woot: will be racing tonight at tyne met for the last round of the series so hope they will last till my spares come.

cheers :thumbsup:

Andyp
19-12-2011, 03:09 PM
i would maybe put a few shims in if you have them to try and save what you have left , although on the very slippy floor you run on @ tyne met they shouldnt be as much load on the diffs as they was last night on the carpet.

The mesh should be similar to your spur/pinion mesh when you rebuild , im sure he told you that maybe.

Sounds like you have some work to do over chrimbo, have you ordered new gears ? might be an idea to replace your plates,thrust and balls maybe while you have it all apart if you wasnt doing that !

Hog
19-12-2011, 04:07 PM
My indoor (polished wood) car is shimmed as per the manual, with 4 shims on the crownwheel side and 3 on the other. My outside car is shimmed 5/2, just to push the crownwheel over slightly and tighten the mesh to cope with the extra oomph from running modified.