 | Home > Maintenance & Modifications > TDCi hub bearing end float - purple spacers ??? |
 
|
|
|
) if if I want to have em at the ready, or do I just use the ones I have?
| Alien Member Since: 18 Jan 2015 Location: Bacchus Marsh Posts: 230  
|
There are 2 items doing different things you have mentioned.
1/ The shim, part 12 is to take up the gap between the drive flange and the sirclip that locates the axle/half shaft. In this case I would reuse the one you have if it looks ok on inspection. 2/ The spacer is in between the wheel bearings is used set the preload. It allows for variation in the hub's manufacture. The bearings have very fine manufacture tolerance. If changing bearings you can reuse the original spacer. If changing the hub you need to select the spacer( or convert to the 2 nut system, see further down). To select the shim you... -Fit a small spacer(purple?). -Torque the bearings to a mid range figure. -Meashure and record the end float. - Do the maths of "spacer+end float-pre load=required spacer" -Strip it all down and fit the spacer required. -Refit and tighten to specification with a new nut and stake the nut. A few folk have converted to the old 2 nut system and removed the spacer. This is how the bearings have been done for many years. You need to set the preload with this method. I converted to the 2 nut system and retained the spacer. -Do the first nut up as tight as possible. -Fit lock tab. -Tighten 2nd nut up to lock it all together. -Bend tabs over and jobs done. This allows it to be undone without pipes as extenders on the side of a track if needed. Hope that long winded answer helps. Cheers, Kyle. Cheers, Kyle. Last edited by Alien on 16th Jun 2016 5:24am. Edited 1 time in total |
||
16th Jun 2016 4:45am |
|
| agentmulder Member Since: 16 Apr 2016 Location: Outer Space Posts: 1324 
|
Kyle,
Perfect infos. OK, looks like I was stuffing up exactly what that video was trying to teach: the difference between pre-load and end-float. Alright, will go with original spacer as I'm only swapping bearings, your comment re. manufacturing tolerances makes sense. The reason I got it wrong re. shims on the outside was because my vehicle doesn't appear to have any  - this made me make sense where there was none to be made. 
Anyway, so now the penny drops I'm wondering WTF is going on with my hubs - there is a wee bit of end float, but not 'no spacers' worth. There is a fair bit of corrosion in there, maybe they've just superficially disappeared. Will be interesting to see the state of the plain thrust washers too... Sooner I order the parts the better. Thanks much cobber - top work. Solved the bowel problem, working on the consonants... |
||
|
16th Jun 2016 5:00am |
|
| Alien Member Since: 18 Jan 2015 Location: Bacchus Marsh Posts: 230
|
I also have no spacer shims on 3 of the 4 flanges.
Make sure you grease the splines in the drive flanges, I even fill my rubber cap to know its full. The best part of this job is for once I don't have to pack the bearings  Cheers,
Kyle. |
||
|
16th Jun 2016 5:08am |
|
| tuesdayfox Member Since: 23 Jun 2013 Location: Sydney,OZ Posts: 129 
|
I have done the very same thing myself, converting the puma wheel bearings to the 2 piece system.
four of the prelaad spacers are now sitting in my toolbox. Last edited by tuesdayfox on 16th Jun 2016 8:25am. Edited 1 time in total |
||
|
16th Jun 2016 8:23am |
|
| tuesdayfox Member Since: 23 Jun 2013 Location: Sydney,OZ Posts: 129
|
I dont have any shims too on all of my flanges..... Will I be in some sort of trouble later on? cheers |
||
|
16th Jun 2016 8:25am |
|
| agentmulder Member Since: 16 Apr 2016 Location: Outer Space Posts: 1324
|
Two possibilities IMO (although I obviously can't claim to be an expert)
- The thrust washers were all new and the system didn't need them. - The mech didn't install them. I'd lift up each wheel and give em a good wiggle. No wiggle= likely OK. Wiggle= needs attention, could be the swivel bearings too .. (right?) I've never done this, but have read a bit about it lately. Solved the bowel problem, working on the consonants... |
||
|
16th Jun 2016 8:36am |
|
| blackwolf Member Since: 03 Nov 2009 Location: South West England Posts: 17209  
|
The halfshaft end-float control shims are generally only found on the front axle where they control the position of the CV joint. They serve no purpose on the rear (it doesn't matter if the rear halfshafts can float).
If you fit new bearings and reuse the original spacer (whether you use the later single stake nut or earlier two-nut retaining system) be careful as you tighten the nut down. Although bearings are made to very fine tolerances, it cannot be guaranteed that the spacer will be correct. When I fitted new rear bearings on my 110, the hub was far too tight with the original spacer, despite the old and new bearings being the same make and the same manufacturer's part number - I was very surprised at this, but it was the case. In the end I ditched the spacer and went 'old school'. There are arguments for and against the spacer system compared to the old two-nut system, but both are totally satisfactory when assembled correctly. If you have the luxury of a stillage full of spacers, the spacer route makes some sense. If you are a normal owner/maintainer, the two-nut method is quicker, simpler and cheaper. The worst feature of the later system is the abhorrent stake nut, and invention of the devil and a good example of disposable engineering at its worst! If you do continue with the stake nut, by the way, I suggest not buying Britpart ones. I made this mistake once, and ended up replacing a stub axle after the out-of-tolerance thread on the nut damaged the thread on the stub axle beyond reuse. I was not happy. |
||
|
16th Jun 2016 8:55am |
|
| agentmulder Member Since: 16 Apr 2016 Location: Outer Space Posts: 1324
|
I can't recall the exact LR ToolBx video but it covers both types, maybe it used a DTI? Keen to get mine doing something useful again, so all good either way.
210Nm and staking nuts dounds painful though, think I might go old school 
If parts are cheap enough, I might get a dual set... Bearmach or better, not britpart... (I understand there's no guarantee of quality but I do draw the line on brirpart for stuff like this) LR original kinda crazy prices, 300£ for a thrust washer!😭 Solved the bowel problem, working on the consonants... |
||
|
16th Jun 2016 9:14am |
|
| blackwolf Member Since: 03 Nov 2009 Location: South West England Posts: 17209
|
Not surprising really since the guy presenting the video appears to have no idea what the term "preload" actually means. Neither of the two arangements preloads the bearings, both are methods of setting the end float correctly. You never under normal circumstances preload opposed taper roller bearings. |
||
|
16th Jun 2016 9:19am |
|
| agentmulder Member Since: 16 Apr 2016 Location: Outer Space Posts: 1324
|
I'm working back stage on an opera at the moment (magic flute
 )... anyhoo, I can't watch the video right now. But I thought that being tapers the first nut would put them under compression, which is what I assumed is pre-load?
Looks like I need a good read about it before continuing discussion Solved the bowel problem, working on the consonants... |
||
|
16th Jun 2016 9:24am |
|
| blackwolf Member Since: 03 Nov 2009 Location: South West England Posts: 17209
|
Yes, tightening the inner nut in that way would preload the bearings but would make them (a) run hot and (b) fail prematurely.
Opposed taper roller bearings are set up so that there is either minimal or zero end float, but zero preload. The reason is that due to the taper angle, relatively small axial loading (preload) causes very much larger radial loading, which causes friction, which causes heat, which causes lubrication problems, which leads to failure. If there is excessive end float, axial load on the bearings (such as when cornering) will cause the rollers to run misalign on the roller paths, which resuls in point contact between rollers and path, which results in massive localised loading, which results in excessive wear and event roller and path breakup leading to bearing failure. There's a lot more applied mechanics going on in the hubs than many people realise! With the two nut system, the first nut is screwed in to take up the end float, the second nut then locks the first. The WSM as I recall instructs you to tighten the first nut until there is minimal but specific endfloat (.001" if I recall), but the reason for this is that when you tighten the lock nut onto the first nut (with the tab washer in between, of course) you actually tighten the first nut a touch more, due to tolerances in the thread form and elastic deformation of the components involved) the overall result should be zero end float with zero preload. In practice it is simple enough to set up. Assemble the hub with bearings and the first nut just pinched up. Fit the wheel, and spin the wheel to settle the bearings. Rock the wheel (both at the 6/12 oclock and 3/9 oclock positions) and adjust the nut until you can just feel very slight movement, then tighten the nut until the movement just becomes imperceptible. Fit the tab washer and locknut and tighten the locknut, and spin the wheel to check it runs freely and smoothly and without any tighness. Rock the wheel again and check that there's no movement. If tight at all, slacken the nuts off and try again. If OK bend over the tab washer. It is right when you tightened it to the point that there is no rocking movement at all, but also no tightness (preload) at all. It takes a little practice but when you get the hang it is easy. |
||
|
16th Jun 2016 9:53am |
|
| agentmulder Member Since: 16 Apr 2016 Location: Outer Space Posts: 1324
|
ugh...
So I'm unsure about some conflicting info online. Catalogs say that for KA onwards the bearings are STC4382, whereas older model bearings are RTC3429 (the two nut system). The thick plottens as LRDirect say that RTC3429 'supersedes' to STC4382 and that "you can still buy the item using any options shown below": https://www.lrdirect.com/STC4382-Hub-Beari...0-110Rrds/ OK ... but there is a price difference of x1.6 between the Timken bearings that are apparently equivalent. https://www.lrdirect.com/RTC3429-Hub-Bearing-Most-Models-Repl/ So, what's going on here? There is a difference (?) or LRDirect don't realise they're advertising a product that they state is the same thing, but in the same breath have two different prices ?? (I wonder which one I'll buy  ) Solved the bowel problem, working on the consonants... |
||
|
17th Jun 2016 12:26am |
|
| tuesdayfox Member Since: 23 Jun 2013 Location: Sydney,OZ Posts: 129
|
woo those are really good prices!
just in case you might want to go retro; I purchased the following parts (and they worked thankfully: -8 drive flange gaskets R571752 GASKET - DRIVE FLANGE - L/R DEF+DISC 1+R/RO -8 bearings STC4382 WHEEL BRG - L/ROV+R/ROV (FRONT+REAR)(TIMKEN) -6 inner seals FTC4785 OIL SEAL - HUB - F+R - L/R DEF+DISC (INNER) -8 x Locknuts - FRC8700- (to conver the puma nut to td5 settings) -4x Lockwasher - FTC3179 (to conver the puma nut to td5 settings) -4 one shot grease STC3435 GREASE - SWIVEL HUB - L/ROV+R/ROV (ONE SHOT SACHET) $88 -4 FTC5241 WASHER - STUB AXLE - L/ROV (THRUST) if you want to save a few bucks, you dont really need to get new thrust washers (the puma setup has them in place cheers Martin |
||
|
17th Jun 2016 2:20am |
|
| agentmulder Member Since: 16 Apr 2016 Location: Outer Space Posts: 1324
|
6 inner seals?
4 One shots? 2 spare of each? I can understand the lube, but the seals, are they the important ones separating axle fluids from hubs? 8 gaskets? I suppose they're the first to come off in all cases... I ordered 10, got em very cheap in bulk. Solved the bowel problem, working on the consonants... |
||
|
17th Jun 2016 2:33am |
|
|
|
| All times are GMT + 1 Hour |
< Previous Topic | Next Topic > |
Posting Rules
|
Site Copyright © 2006-2024 Futuranet Ltd & Martin Lewis
