[Robert42]

My dealer has spent all day unsuccessfully trying to identify.a clonking/rattle from underneath. This happens when driving over rough roads, but not all the time but seems more obvious as the car warms up. Has anyone else had this?

 

[makem]

I had this a few weeks after purchase. The garage put a mic underneath and drove around, eventually finding that an exhaust baffle was loose. (so they said)

I still experience 'noise' underneath when I drive along the road to my home but nowhere else that I have noticed. There is nothing different in the road surface to other roads.

My son-in-law who has some knowledge traveled in the car with me along this road and says any noise he hears is quite normal for a stiff car with hard tyre pressures that I use.

I describe the noise as being as if the floor of the car consisted of wooden planks or there were wood planks under the floor and these rattled quite loudly as we drove along that road. I have had two other cars whilst living in that road and can remember nothing like this. Today I just try to ignore it.


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Edited by: makem

 

[Robert42]

Yes that describes the noise quite well. It would appear to be temperature or heat related as the weather is cold todaycompared to the last few weeks and it was not as noticeable.

 

[paulhic8]

Mine has the same rattle underneath but only happens in my street and nowhere else.

 

[makem]

Do you think maybe the B-MAX knows where it is and is pleased to be nearly home?

Mine does the same!

 

[paulhic8]

Its weird now.

 

[Modestmillionaire]

Hi all
I had the same problem with banging underneath -front end low down.
Went into dealers about 3 times with no sucess.
I kept taking it back as I am ex Rolls Royce and Bentley engineer and dont accept anythingsuch asrattles.
Anyway the problem was the windscreen washer bottle banging on the longeron.

Same old story, great concept car, poor build and quality control.

 

[makem]

Hi all
I had the same problem with banging underneath -front end low down.
Went into dealers about 3 times with no sucess.
I kept taking it back as I am ex Rolls Royce and Bentley engineer and dont accept anythingsuch asrattles.
Anyway the problem was the windscreen washer bottle banging on the longeron.

Same old story, great concept car, poor build and quality control.

I would like to check that but what it a longeron - a cross member near the bottle?

 

[Modestmillionaire]

Hello Makem
A longeron is a stiffening member that runs fore and aft to which the inner wing is fastened. Although an aeronautical term, it is used in the automobile industry for monocoque bodies.

You are now going to ask "what the dickens is a monocoque body"?

It is a body where the outer skin supports all the stresses. In old cars a chassis was used to take all the load.

If you look under the washer bottle, you will see the top of the longeron. The bottle appears to be sitting on it and there is no apparant movement. However, on a ridged road when the wheels begin to patter,a significant bangingcould be heard - no doubt magnified by transmission through the body like a drum. My solution was to put rubber packersbetween the bottle and longeron.
It was an amazing success but took some finding.

Hope this is all that is causing your problem.

 

[makem]

Thanks, I will check tomorrow. Perhaps the road where I live causes a sympathetic vibration where you say rather than the car knowing it is near home.

I did know the meaning of a monocoque body as that is one of the designs which brought about a big reduction in passenger injury. (I think, not being expert.)

 

[makem]

Checked today and found that the water bottle is fitted very tight to the longeron. It takes quite a bit of force (much more than the weight of water inside), to raise it maybe 2mm.

As it is in effect pressing down heavily on the longeron I doubt if there would be any vibration there. It would be quite difficult to get any sort of buffer in there due to restricted access.

Thanks for the info but I must keep looking. (Or use another way home)

 

[Modestmillionaire]

Thanks, I will check tomorrow. Perhaps the road where I live causes a sympathetic vibration where you say rather than the car knowing it is near home.

I did know the meaning of a monocoque body as that is one of the designs which brought about a big reduction in passenger injury. (I think, not being expert.)

Hope you can sort it. With mine, dropping into a pothole or very rough road did not cause it.It always happened as I said on a ridged surface where there was a frequency set up. and the wheels pattered.
Good luck and persevere.
PS Like your pics especially Madeira, happy memories.

 

[Modestmillionaire]

Checked today and found that the water bottle is fitted very tight to the longeron. It takes quite a bit of force (much more than the weight of water inside), to raise it maybe 2mm.

As it is in effect pressing down heavily on the longeron I doubt if there would be any vibration there. It would be quite difficult to get any sort of buffer in there due to restricted access.

Thanks for the info but I must keep looking. (Or use another way home)

You are correct, it does feel that it presses heavily and that there is no reason for it to vibrate - but believe me it will sound throughout the body.
Ease it up and try to fit a pad underneath it. Card will do just to test it.

 

[makem]

Have you got a spare child to squeeze his/her hands down there for me? lol

Yes I will try when I can find something suitable but not looking forward to it.

 

[Robert42]

Hi all
I had the same problem with banging underneath -front end low down.
Went into dealers about 3 times with no sucess.
I kept taking it back as I am ex Rolls Royce and Bentley engineer and dont accept anythingsuch asrattles.
Anyway the problem was the windscreen washer bottle banging on the longeron.

Same old story, great concept car, poor build and quality control.

How did you determine it was the washer bottle? I looked on mine and there was only a very small amount of movement.

Now that the weather is colder, the noise seems to have stopped so I am wondering if the 'stiffness' of the plastic components has something to do with it.

 

[Modestmillionaire]

Robert
There is no easy way to diagnose where the noise comes from, it is just a matter of making a judgement as to what is possibly causing the problem, anddo whatever it takes toeliminate it. Only tackle one potential problem area at a time and then do a prolonged test drive. It really is trial and error.
Good luck and lots of patience.

 

[smart1]

Hi im new to Forum, got my 1.4 Zetec in June Brill. Recently noticed woody sort of sound from rear. Removed parcel shelf still noise. Removed storage cover still noise. Pushed in headrests laid rear seats flat noise stopped. I think alot of clonks and rattles and woody sounds come from rear seat set up. Mainly the seat base and catches.

 

[raceredrog]

I had this similar banging / clunking when travelling over uneven or ridged surfaces. Local Ford dealer confirmed there was a noise but couldn't identify it and wouldn't investigate under warranty ( car is nearly 2 yrs old). Returned yesterday to Ford dealer from whom purchased. They didn't seem to have a problem investigating under warranty. Outcome (subject to more road testing by me) is that they have re greased brake pins to stop them rattling. Seems to have worked so far.