Sirocco Posted July 16, 2011 Share Posted July 16, 2011 follwing up from my diff thread further down, I had my truetrac (in Rover Diff) checked by Bristol Transmissions and they adjusted the backlash for me as they said it was a little excessive. Im pretty sure they looked it over and deffo spread that engineers blue stuff around. This was all fine as it confirmed my suspicions. Anyway, fitted it all back in with my original halfshafts and it all felt fine with no slack in the driveline (which was nice). Anyway, I noticed yesterday that its now whining or whirring rather which is only noticable when applying a little power at or just over 30mph. coasting I cant hear it, but a little squeeze of the throttle and it whirrs along So... I google'd around and found on the Aussy forum that: 'Don;t get excitited with the backlash and the spec, if it drove fine before, refit the same, otherwise "correcting" the backlash you may well end up with an unpleasant whine aside from the wife'. so... my question is: will this set-up now have a negative effect in anyway? and will the whine dissepate with time/mileage? should I take it back to Bristol Transmissions or just live with it? Any advice (again!) most appreciated. Cheers Gents. G Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted July 16, 2011 Share Posted July 16, 2011 I would question how good they are - frankly if they can't get it right 1st time don't go back, it should have been done properly in the 1st place shame your a distance from Steve & I sounds as if its more than bashlas adjustment to be honest - needs properly looking at by a grown up who knows exactly what they are doing Nige Quote Link to comment Share on other sites More sharing options...
Sirocco Posted July 16, 2011 Author Share Posted July 16, 2011 Hi Nige, Yes, I did contemplate getting it to you guys as I have a mate in Bracknell (who knows Steve well) but they were recommended by a good landy independent garage here in Bristol so I thought nothing of it. They also had a number of Rover diffs on the shelf from customers. Is the whirr comeing from an incorrect mesh of the C&P rings? Do you think this is going to cause problems? G Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted July 16, 2011 Share Posted July 16, 2011 Hi Nige, Yes, I did contemplate getting it to you guys as I have a mate in Bracknell (who knows Steve well) but they were recommended by a good landy independent garage here in Bristol so I thought nothing of it. They also had a number of Rover diffs on the shelf from customers. Is the whirr comeing from an incorrect mesh of the C&P rings? Do you think this is going to cause problems? G Without looking at it could be anything... Could be that the pinion height was never right, this then causes odd wear (fast) when reset it then is worn in such a way it doesn't mesh "Nicely" and the CW&P is fubared, could be wear / slack in bearings and or just not done properly, ie they have reset the bashlash "Thats what Sir asked for" but thats all we did, and the x y z is not right but we didn't touch that etc etc etc Without looking at it / pulling it apart properly inspecting you'll not find out the prob Sorry, dats the way it is, however, if you wnat to "Come on down" with it at an agree time for all, Steve would do it whuile you wait and watch and learn theres more to diffs than mostr peeps will ever know, thats why I don't even think of building / sorting duiffs Nige Quote Link to comment Share on other sites More sharing options...
Sirocco Posted July 16, 2011 Author Share Posted July 16, 2011 Without looking at it could be anything... Could be that the pinion height was never right, this then causes odd wear (fast) when reset it then is worn in such a way it doesn't mesh "Nicely" and the CW&P is fubared, could be wear / slack in bearings and or just not done properly, ie they have reset the bashlash "Thats what Sir asked for" but thats all we did, and the x y z is not right but we didn't touch that etc etc etc Without looking at it / pulling it apart properly inspecting you'll not find out the prob Sorry, dats the way it is, however, if you wnat to "Come on down" with it at an agree time for all, Steve would do it whuile you wait and watch and learn theres more to diffs than mostr peeps will ever know, thats why I don't even think of building / sorting duiffs Nige yes i hear its a dark art they checked the pinion and said it was ok and the chap I bought it off said it had new bearings installed, but I guess I will never know... balls! Have to have a think on this one, thanks for the advice G Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted July 16, 2011 Share Posted July 16, 2011 Hmmmmmmm You can't check pinion height without fully removing the diffs centre ....did they ? Quote Link to comment Share on other sites More sharing options...
Sirocco Posted July 16, 2011 Author Share Posted July 16, 2011 No because they only charged 1 hour. If they pulled it apart they said it would take 2-3 hours. Would it have been pinion preload? G Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted July 16, 2011 Share Posted July 16, 2011 No because they only charged 1 hour. If they pulled it apart they said it would take 2-3 hours. Would it have been pinion preload? G Nope To change the pinion preload you hacve to take out the Centre of the diff AND the pinion ! I fink they charged you 1 hour for "Tightening" bodgering it tighter which has solved one issue and caused a bigger one Nige PS - Go on, make my day - what was "1 hours Labour" then ? Quote Link to comment Share on other sites More sharing options...
Sirocco Posted July 16, 2011 Author Share Posted July 16, 2011 Nope To change the pinion preload you hacve to take out the Centre of the diff AND the pinion ! I fink they charged you 1 hour for "Tightening" bodgering it tighter which has solved one issue and caused a bigger one Nige PS - Go on, make my day - what was "1 hours Labour" then ? No not change the preload, but to check it. They said it seemed fine so didn't take the time to stip the diff down and then just got on with the backlash. Because I never fitted the diff 1st I dont know if it was whining before or not. I just wanted it inspected before going through the trouble of fitting it. The price is in my other thread scary stuff. G Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted July 16, 2011 Share Posted July 16, 2011 £75 ? For ONE hours Labour which sounds like 10 mins bodging the backlash :rofl: Kin ell Nige Quote Link to comment Share on other sites More sharing options...
inaine Posted July 16, 2011 Share Posted July 16, 2011 crown diff dismantled 2 x truetrac diffs, new bearings and turned one round to run in the front for £110 inc you have been mugged my friend Quote Link to comment Share on other sites More sharing options...
Sirocco Posted July 16, 2011 Author Share Posted July 16, 2011 £75 ? For ONE hours Labour which sounds like 10 mins bodging the backlash :rofl: Kin ell Nige Allright, no need to rip the P£$% Quote Link to comment Share on other sites More sharing options...
Hybrid_From_Hell Posted July 16, 2011 Share Posted July 16, 2011 Allright, no need to rip the P£$% Sorry, more like morbid amazement Nige Quote Link to comment Share on other sites More sharing options...
Off Road Toad Posted July 17, 2011 Share Posted July 17, 2011 The advise on the Aussy forum is pretty good actually. If you take a CWP set that have done say 100k miles of hard labour and then re-set the backlash to the closest tolerance for example, then you will get whining. The gears will have worn themselves to a comfortable pattern and if you alter this pattern they're not gonna like it. When we get asked to fit a replacement second hand CWP set we do so only with the best cherrypicked ones we have, all the others get binned. Its always best to fit a new set of CWP but not everyone has spare cash to spend so we do what we can for them if they've had some bad luck. You cannot check a diff's settings by giving it a cursory glance over! you can see for wear patterns on the gear teeth but thats about it. Its not Pete that you know in Bracknell is it? Regards, Steve Quote Link to comment Share on other sites More sharing options...
Les Henson Posted July 17, 2011 Share Posted July 17, 2011 Bit late now, but a used diff that's being rebuilt after excessive backlash will almost certainly have unevenly worn crownwheel/pinion teeth. Quite often the contact patch on the teeth can be seen to be off centre, and therefore the teeth are realistically worn out and shouldn't be used. The whine is usually the result of poor tooth mesh. If the diff was totally rebuilt with new bearings/preload set, etc, etc - you would probably still have the noise if the old pinion and crownwheel are used. Les. Quote Link to comment Share on other sites More sharing options...
Sirocco Posted July 17, 2011 Author Share Posted July 17, 2011 The advise on the Aussy forum is pretty good actually. If you take a CWP set that have done say 100k miles of hard labour and then re-set the backlash to the closest tolerance for example, then you will get whining. The gears will have worn themselves to a comfortable pattern and if you alter this pattern they're not gonna like it. When we get asked to fit a replacement second hand CWP set we do so only with the best cherrypicked ones we have, all the others get binned. Its always best to fit a new set of CWP but not everyone has spare cash to spend so we do what we can for them if they've had some bad luck. You cannot check a diff's settings by giving it a cursory glance over! you can see for wear patterns on the gear teeth but thats about it. Its not Pete that you know in Bracknell is it? Regards, Steve Morning Steve, yes that was my thought process after reading what was said on the Aus forum. hmmm... So it looks like I should do something about it then Yes it is Pete. We travelled a bit together in Morocco and were meant to go to West Africa earlier this year, but he couldn't get the time in the end, shame it was a good trip! G Quote Link to comment Share on other sites More sharing options...
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