ausmini :: View topic - Gearbox or diff noise?

Are any of the gearsets, drop/transfer gears or diff pinion/crownwheel gears straight cut? That could explain the whine.

Are any of the gearsets, drop/transfer gears or diff pinion/crownwheel gears straight cut? That could explain the whine.

Sent from my Pixel 3 XL using Tapatalk

PS parts in this car are British...whine can be normal!

Great thinking 99 :!:

Jack the car up on the drivers side, pull the sump plug, stop any minor oil flow, and check what you have sticking to the magnet...

Clean it off, put it back in and run it for a while to see what sticks to the magnet again...it may all be OK :idea:

[PS parts in this car are British...whine can be normal!]

Yep thanks guys, you are right, it does change with the revs. Should have thought of that myself and ruled out diff - especially given the number of diffs I've changed over in various 'classic' English cars I've subjected myself to. But not having worked on this level of mini engines before, I'm still on a steep learning curve when it comes to things like drop gears etc.

Be interesting to see if it has straight cut gear set in it as Morbo28 suggested.

Quote:

If it has a breather on the flywheel housing you could take that off and look down the hole with a horoscope,

simon k wrote:

Quote:

If it has a breather on the flywheel housing you could take that off and look down the hole with a horoscope,

Hope a Borescope doesn't prove to be a Horror Scope...

Love the humour.
Certainly made me chuckle

Author:	clip [ Wed Sep 16, 2020 10:51 am ]
Post subject:	Gearbox or diff noise?
The link is a short video of my 850 (the audio is modified to help with hearing the whine). The gearbox was supposed to have been reco'd and TBH it shifted really well, synchros were all great, no jumping out of gear etc. However, it does scream in any gear when loaded i.e. accelerating and de-accelerating. So thinking that it's diff - maybe crown and pinion wear? https://www.youtube.com/watch?v=AMNx3C27JRs

Author:	Morbo28 [ Wed Sep 16, 2020 6:20 pm ]
Post subject:	Re: Gearbox or diff noise?
Are any of the gearsets, drop/transfer gears or diff pinion/crownwheel gears straight cut? That could explain the whine. Sent from my Pixel 3 XL using Tapatalk

Author:	clip [ Wed Sep 16, 2020 6:32 pm ]
Post subject:	Re: Gearbox or diff noise?
Morbo28 wrote: Are any of the gearsets, drop/transfer gears or diff pinion/crownwheel gears straight cut? That could explain the whine. Not sure what’s in it as haven’t pulled it down, but hadn’t thought of that. Certainly what it sort of sounds like though. Just trying to do up a costing to see if it’s all worthwhile as I’m still toying with dropping the 850 back in and keeping the 1310 for another project - if I can find a good body somewhere.

Author:	9YaTaH [ Thu Sep 17, 2020 10:21 am ]
Post subject:	Re: Gearbox or diff noise?
Morbo28 wrote: Are any of the gearsets, drop/transfer gears or diff pinion/crownwheel gears straight cut? That could explain the whine. Sent from my Pixel 3 XL using Tapatalk Great thinking 99 Jack the car up on the drivers side, pull the sump plug, stop any minor oil flow, and check what you have sticking to the magnet... Clean it off, put it back in and run it for a while to see what sticks to the magnet again...it may all be OK [PS parts in this car are British...whine can be normal!]

Author:	winabbey [ Thu Sep 17, 2020 11:30 am ]
Post subject:	Re: Gearbox or diff noise?
9YaTaH wrote: PS parts in this car are British...whine can be normal! True, but usually the whine comes from the owner while waiting for the tow truck.

ausmini https://www.ausmini.com/forums/

Gearbox or diff noise? https://www.ausmini.com/forums/viewtopic.php?f=2&t=100391	Page 1 of 2

Author:	clip [ Thu Sep 17, 2020 11:40 am ]
Post subject:	Re: Gearbox or diff noise?
9YaTaH wrote: Great thinking 99 Jack the car up on the drivers side, pull the sump plug, stop any minor oil flow, and check what you have sticking to the magnet... Clean it off, put it back in and run it for a while to see what sticks to the magnet again...it may all be OK [PS parts in this car are British...whine can be normal!] this is really loud whining though, like you hear it coming down the road loud. I did do a couple of oil changes when I first got it, all good (I’m OCD when it comes to oil changes). The oil stayed clean as, virtually nothing on the magnet, however, not to say that the previous owner didn’t do a few last minute oil changes.

Author:	simon k [ Thu Sep 17, 2020 9:37 pm ]
Post subject:	Re: Gearbox or diff noise?
From the video, it sounds like the sound gets louder with revs and drops when you change gear so it couldn't be the diff. It has to be on the engine side of the gearbox - primary gear or idler....

Author:	Oscar [ Fri Sep 18, 2020 8:55 am ]
Post subject:	Re: Gearbox or diff noise?
Yeah I agree - it's engine speed related. 40 years ago the wife's car sounded exactly like that and I kept putting off investigating until one morning on her way to work the outer idler bearing let go!!

Author:	clip [ Fri Sep 18, 2020 10:45 am ]
Post subject:	Re: Gearbox or diff noise?
Yep thanks guys, you are right, it does change with the revs. Should have thought of that myself and ruled out diff - especially given the number of diffs I've changed over in various 'classic' English cars I've subjected myself to. But not having worked on this level of mini engines before, I'm still on a steep learning curve when it comes to things like drop gears etc. Be interesting to see if it has straight cut gear set in it as Morbo28 suggested.

Author:	9YaTaH [ Fri Sep 18, 2020 4:24 pm ]
Post subject:	Re: Gearbox or diff noise?
clip wrote: Yep thanks guys, you are right, it does change with the revs. Should have thought of that myself and ruled out diff - especially given the number of diffs I've changed over in various 'classic' English cars I've subjected myself to. But not having worked on this level of mini engines before, I'm still on a steep learning curve when it comes to things like drop gears etc. Be interesting to see if it has straight cut gear set in it as Morbo28 suggested. Find a slight down hill, slip it into nuetral, vary engine revs a little and that should (maybe) isolate the noise to engine rather than box? (and vikky verka)

Author:	simon k [ Fri Sep 18, 2020 6:15 pm ]
Post subject:	Re: Gearbox or diff noise?
[Quote] Be interesting to see if it has straight cut gear set in it as Morbo28 suggested.[/quote] It does sound like straight cut drop gears, but you'd think the seller would mention that as a selling point. They're not cheap... If it has a breather on the flywheel housing you could take that off and look down the hole with a horoscope, you should be able to see the primary gear teeth

Author:	9YaTaH [ Fri Sep 18, 2020 7:12 pm ]
Post subject:	Re: Gearbox or diff noise?
simon k wrote: Quote: If it has a breather on the flywheel housing you could take that off and look down the hole with a horoscope, Hope a Borescope doesn't prove to be a Horror Scope...

Author:	Phil 850 [ Fri Sep 18, 2020 8:28 pm ]
Post subject:	Re: Gearbox or diff noise?
9YaTaH wrote: simon k wrote: Quote: If it has a breather on the flywheel housing you could take that off and look down the hole with a horoscope, Hope a Borescope doesn't prove to be a Horror Scope... Love the humour. Certainly made me chuckle .

Author:	9YaTaH [ Sat Sep 19, 2020 6:35 am ]
Post subject:	Re: Gearbox or diff noise?
Phil 850 wrote: Love the humour. Certainly made me chuckle . Time's are tough Phil...a little humour goes a long way

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Author:	clip [ Sat Sep 19, 2020 8:56 am ]
Post subject:	Re: Gearbox or diff noise?
Hmm, I don’t have one of those scopes, but I do have to have a colonoscopy soon. I wonder if the doc would lend me his - after he’s cleaned it of course!