knocking from the rear

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dext924

knocking from the rear

Post by dext924 » Wed Oct 13, 2010 4:32 pm

This one has me puzzled. When I start a journey, I get a bit of a knocking/banging noise from the back of the Bongo. After reading some past posts, I checked the usual joints, rubbers etc. If I didn't know better, I would say it was the spare wheel rattling, its that sort of noise, but that is solid. It doesn't sound a metal noise, more like a plastic knocking noise. I have been under the Bongo and shook and pushed at anything that might make a noise, but nothing. Once I have been running for a while, it dies off. It doesn't happen over every bump, and sometimes more over uneven road.

Is there anything that could have come lose that I have missed? Its one of those annoying things that i would like to get looked at, and more annoyed at the fact that I don't know what it is :x :x

Any ideas chaps and chapesses?
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mikeonb4c
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Re: knocking from the rear

Post by mikeonb4c » Wed Oct 13, 2010 4:56 pm

dext924 wrote:This one has me puzzled. When I start a journey, I get a bit of a knocking/banging noise from the back of the Bongo. After reading some past posts, I checked the usual joints, rubbers etc. If I didn't know better, I would say it was the spare wheel rattling, its that sort of noise, but that is solid. It doesn't sound a metal noise, more like a plastic knocking noise. I have been under the Bongo and shook and pushed at anything that might make a noise, but nothing. Once I have been running for a while, it dies off. It doesn't happen over every bump, and sometimes more over uneven road.

Is there anything that could have come lose that I have missed? Its one of those annoying things that i would like to get looked at, and more annoyed at the fact that I don't know what it is :x :x

Any ideas chaps and chapesses?
Apart from your comment in red above, I'd say droplinks and/or antiroll bar bushes/brackets were a suspect unless you can confirm they have been replaced recently. It is not necessarily easy to tell just by pushing and shaking by hand, as the knocking noise happens when the bushes are relieved of their load, which is more than you can achieve by hand.

I presume your exhaust insn't clonking against anything (give that a good shake etc.).
dext924

Re: knocking from the rear

Post by dext924 » Wed Oct 13, 2010 7:07 pm

Well, I have got under the truck and given it a good dig, and seems solid, but as you say, I might not be strong enough! they seem in good order upon closer inspection though, but I am no expert. It sounds like the jack or something like that is rattling around, but I have run with all that gumph taken out and its still there.

I'm a bit baffled :?: :?:
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Re: knocking from the rear

Post by Triple/R » Wed Oct 13, 2010 7:20 pm

As Mike said,anti roll bar bushes~~~it happened on mine,but the front ones~~i took the front wheels off god knows how many times & even tested them & other things with a really long crow bar with no movement whatsoever~~eventually i replaced roll bar brackets & bushes,i compared new bushes with old but there was'nt a lot of difference but changed them anyway~~ & they stopped all the rumbling & knocking ~~with a comparitively low outlay they well worth changing
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dext924

Re: knocking from the rear

Post by dext924 » Wed Oct 13, 2010 7:32 pm

Thanks guys. I reckon I will get them changed anyway, to see if that stops it. Can't think of anything else it could be really, and at least it will tick them off the list :D

They seem to be the cause of most noises from that area, and lets hope thats all it is [-o< LOL!
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Re: knocking from the rear

Post by bobngo » Wed Oct 13, 2010 8:34 pm

this is way off base but , at the bottom on each side of the rear door,are two rubber door stops, (on the vehicle ,not the door )which are meant to stop the rear door rattling etc, sometimes these get pushed too far inwards, and so need readjusting ,to stop the noise

just a thought !!!
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Re: knocking from the rear

Post by mikeonb4c » Thu Oct 14, 2010 2:38 pm

bobngo wrote:this is way off base but , at the bottom on each side of the rear door,are two rubber door stops, (on the vehicle ,not the door )which are meant to stop the rear door rattling etc, sometimes these get pushed too far inwards, and so need readjusting ,to stop the noise

just a thought !!!
Good thought =D>

For the rest, if you are uncertain when the droplinks etc. were last done, then even if it doesn't cure the noise it will still be a job not wasted, if you get me. 8)
dext924

Re: knocking from the rear

Post by dext924 » Thu Oct 14, 2010 11:33 pm

Thanks to Northern B and Bob for the tips, I checked them tonight and it has made a slight difference! It is still there but only half as bad now, so I think I am in the right area. I presume if it is the bush it will knock all the time? Well it doesn't now, much quieter. Not sure what I should be doing when adjusting, I suppose a tweek at a time until its gone?
They rubber bits seemed tight, just moved them out slightly and as I said, made a bit of a difference :D

Still think I will do the bushes, as you say, it wont be a job wasted.

Will have another tweek tomorrow and see what happens [-o<
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Re: knocking from the rear

Post by dave_aber » Fri Oct 15, 2010 6:28 am

I'm a bit baffled :?: :?:

As it gets better when warmed up, it may be a loose or cracked baffle in the rear box?
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Re: knocking from the rear

Post by Diplomat » Fri Oct 15, 2010 10:51 am

I'm fascinated by what appears to be a weight in a frame at the back of the transmission. Looks like it has the potential to "clonk".

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Re: knocking from the rear

Post by dave_aber » Fri Oct 15, 2010 11:02 am

I noticed that on mine too - some sort of mass damper ?
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dext924

Re: knocking from the rear

Post by dext924 » Mon Oct 18, 2010 10:10 am

Well, I have done both sides now, and it has not cured the problem totally. It has, by some strange coincidence lessened it :?:
The knocking seems a bit plasticy if that makes sense, as though something is knocking on the trim some way.

I will get round to doing the bushes in a week or so when i have some time of work, but I am still scratching me head on this one a bit :roll:
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Re: knocking from the rear

Post by bigdaddycain » Thu Oct 21, 2010 9:01 pm

Have you actually dropped the spare wheel to see if the metal hanger on the cable is the correct way round? I seem to recall reading on here some time back that it was the "wrong way round" meaning the metal of the rim was catching on something. In addition, try popping a folded cloth (temorarily) over each tailgate bumpstop to increase/damp where they come into contact with the tailgate... If it stops the annoying rattle, you know you need to focus your attention there. I couldn't get mine to adjust, so fitted a couple of self adhesive rubber discs on the corresponding "striker point" on the tailgate. :wink: It made no difference though, the rattle on mine was the rear number plate working loose! #-o
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