Chuffing noise
Discussion
Hi,
I'm hoping someone out there could give me a clue to the origin of my latest automotive challenge. My Tasmin started a while back with a strange 'chuffing' noise, too soft to be described as a knock. It seems to be linked to road speed, doesn't change with braking and loudest about 35 mph.It's not noticeably changed by enthusiastic cornering. I've just changed the tyres (originating I find, from the last millennium), and oddly enough this has reduced the noise a lot and changed the speed at which it's noticed to about 45 mph.
But it's still there.
The rear calipers are recentish recons, as is one front one ( I've rebuilt the other) . There's no bearing prob on the front that I can detect, but I can't see how to check the rears as having a LSD I can't 'spin' the rear wheels. There's no play though. Everything looks OK underneath. The hand brake has been adjusted recently but with no change to the noise. Propshaft seems OK.
Before I submit myself to open wallet surgery, anyone have any thoughts?
Thanks,
Ian
I'm hoping someone out there could give me a clue to the origin of my latest automotive challenge. My Tasmin started a while back with a strange 'chuffing' noise, too soft to be described as a knock. It seems to be linked to road speed, doesn't change with braking and loudest about 35 mph.It's not noticeably changed by enthusiastic cornering. I've just changed the tyres (originating I find, from the last millennium), and oddly enough this has reduced the noise a lot and changed the speed at which it's noticed to about 45 mph.
But it's still there.
The rear calipers are recentish recons, as is one front one ( I've rebuilt the other) . There's no bearing prob on the front that I can detect, but I can't see how to check the rears as having a LSD I can't 'spin' the rear wheels. There's no play though. Everything looks OK underneath. The hand brake has been adjusted recently but with no change to the noise. Propshaft seems OK.
Before I submit myself to open wallet surgery, anyone have any thoughts?
Thanks,
Ian
Edited by madformotors on Friday 17th November 13:20
Hi,
Thanks for the suggestions. The previous set of tyres were at the same pressures, and equal (good) tread, but very aged so I changed them yesterday. The new ones are again at the same pressures.
The ujs seem to be OK too, and there's oil in the diff.
BTW the original post had the word "not" in between "it's" and "noticeably" in the preview, but not in the actual post itself! And it won't edit! So for avoidance of doubt, when I corner sharply the chuffing sound DOESN'T change...
Ian
Thanks for the suggestions. The previous set of tyres were at the same pressures, and equal (good) tread, but very aged so I changed them yesterday. The new ones are again at the same pressures.
The ujs seem to be OK too, and there's oil in the diff.
BTW the original post had the word "not" in between "it's" and "noticeably" in the preview, but not in the actual post itself! And it won't edit! So for avoidance of doubt, when I corner sharply the chuffing sound DOESN'T change...
Ian
Thanks for the suggestions guys. I'll certainly give the 'pulling handbrake on' a go while driving to see what happens, although the noise hasn't been affected by the recent adjustment. I can't see a wheel rubbing, but the whole issue is difficult to trace as it's difficult to tell whether the noise is front or back or on one side or the other - it's sort of 'general'. Not helped by the exhaust noise note!
I'm drawn to the tyre/LSD suggestion though because the tyre change the one thing that has made a difference .
I hope it's not wheel bearings - looking at threads on this, it looks to be a real pain!
Ian
I'm drawn to the tyre/LSD suggestion though because the tyre change the one thing that has made a difference .
I hope it's not wheel bearings - looking at threads on this, it looks to be a real pain!
Ian
Update of sorts ....I've finally given up trying to trace the chuffing noise , and taken it in to the professionals to see what they say.
Unfortunately they don't know. It's thought not to be the wheel bearings. Possibly a dry joint on a driveshaft or prop U/J. Or maybe the diff.
Am advised to run it till it gets really noticeable then it'll be easier to identify.
So I'm no further forward really, but not too happy that I'm still in limbo.
I will take the prop off to check the u/j though, that'll be one 'possible' ticked off the list.
Ian
Unfortunately they don't know. It's thought not to be the wheel bearings. Possibly a dry joint on a driveshaft or prop U/J. Or maybe the diff.
Am advised to run it till it gets really noticeable then it'll be easier to identify.
So I'm no further forward really, but not too happy that I'm still in limbo.
I will take the prop off to check the u/j though, that'll be one 'possible' ticked off the list.
Ian
Hi,
I've tried this, but as there's a LSD, the wheels are really difficult to spin. However there doesn't seem to be any play when I try rocking the wheel about.
I'm currently having a ponder about getting the drive shafts off to see what the u/js are like. Never worked on a car with irs before, so all fascinating stuff. That's what I keep telling myself!
Ian
I've tried this, but as there's a LSD, the wheels are really difficult to spin. However there doesn't seem to be any play when I try rocking the wheel about.
I'm currently having a ponder about getting the drive shafts off to see what the u/js are like. Never worked on a car with irs before, so all fascinating stuff. That's what I keep telling myself!
Ian
Edited by madformotors on Tuesday 9th January 18:52
Hi,
Not checked for presence of nipples, though if there are some I'll certainly give them some attention. Have to wait till I get the car back from the garage though.
Not sure if the discs are new (they certainly look OK) but the calipers are new. That said there's no change in the chuffing noise when braking.
Ian
Not checked for presence of nipples, though if there are some I'll certainly give them some attention. Have to wait till I get the car back from the garage though.
Not sure if the discs are new (they certainly look OK) but the calipers are new. That said there's no change in the chuffing noise when braking.
Ian
Closure....chuffing noise now gone.
Thanks for all the helpful suggestions, but it's Mr. Z that gets the gold star - it was the rear wheel bearings after all. There was no noticeable play, I just changed them more in hope than expectation. And what fun that was
Nirvana reigns now chez madformotors, or at least it does till I tackle the wavy veneer. Or the wee hole in the outrigger....
Ian
Thanks for all the helpful suggestions, but it's Mr. Z that gets the gold star - it was the rear wheel bearings after all. There was no noticeable play, I just changed them more in hope than expectation. And what fun that was
Nirvana reigns now chez madformotors, or at least it does till I tackle the wavy veneer. Or the wee hole in the outrigger....
Ian
Hi
Confession time, I didn't actually shift the bearings myself. After a bolt snapped in the hub carrier, I took the carriers to my friendly local garage for them to press it out and change the bearings/oil seals at the same time.
My wife picked the bits up , bless her, so I haven't yet had a run down on what the guys found. I did think that the old bearings ran quite smooth, but I'll give them a call and ask them if they remember what the old ones were like when they got them out.
Confession time, I didn't actually shift the bearings myself. After a bolt snapped in the hub carrier, I took the carriers to my friendly local garage for them to press it out and change the bearings/oil seals at the same time.
My wife picked the bits up , bless her, so I haven't yet had a run down on what the guys found. I did think that the old bearings ran quite smooth, but I'll give them a call and ask them if they remember what the old ones were like when they got them out.
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