Cracking noise on cornering Hymer B544 Fiat A Class 93

[AF1]

Hi, I have a sharp Cracking noise on cornering coming from the L/H side front of the coachwork. 

This only developed at the end of our last trip 2 weeks ago.

Has any member had a similar issue and what was the remedy please?

[snowy]

My first thought would be , drive shaft joint,  and second wheel bearing.

[AF1]

43 minutes ago, snowy said:

My first thought would be , drive shaft joint,  and second wheel bearing.

I have been in the motor trade most of my working life, I believe it is coming frome the coachwork frame.  However I have no experience of wooden framed coachwork apart from Morris Minors 🙂

[Derek Uzzell]

I suggest you check the condition of your Hymer's front coil springs very carefully (I assume the "93" in your posting's title indicates 1993 as the vehicle's year of manufacture).

I'm doubtful that Hymer would have used timber as a main component of its bodywork construction, but, even if they had, I wouldn't expect this to suddenly begin to produce cracking noises when cornering.

On the other hand, there are several on-line comments about front-suspension coil springs breaking on older Hymer A-class models and - although the failures have tended to be 'catastrophic' - occasionally the motorhome was still drivable.

You might try asking about this issue here

https://www.motorhomefun.co.uk/forum/forums/hymer-owners-group.86/

[thebishbus]

I presume it is R/H drive, if so get your passenger  to open their window and listen outside, should be able to tell if the noise is from the suspension  or bodywork.

                   Brian B.

[AF1]

I have found out that Hymer Class As of this period do have a galvanised steel space frame, which is very minimal in the front corners.  Some owners have fitted extra bolts to remove any 'slack' and the plywood dashboard acts as stiffening if unrotted and well secured!!

 

Edited September 21, 2023 by AF1
error

[AF1]

Thanks everyone for your input.

[Brian Kirby]

FWIW, I'd suggest getting the front suspension and its mounting points, the drive shaft CVJs, and wheel bearings all checked by a suitably competent garage as the first priority.  That should eliminate items liable to result in serious risks to life and limb.  Thereafter, other sources of the noise should not relate to anything actually dangerous.

My reservation is your reference to a "galvanised steel space frame".  This is a 30 year old vehicle, and contrary to the beliefs of many, "galvanising" does not provide everlasting protection to mild steel, and not all "galvanising" is equal.

So, given the age of the vehicle, and that it may have been driven quite extensively on salted roads, where the resulting road spray will have left a corrosive salt crust on exposed underbody metalwork, to the detriment of any galvanised steel, I would not eliminate the possibility of serious localised corrosion from my thinking.

Also, bear in mind that the life of the zinc coating, however it was applied, is proportionate to the thickness of the coating, and many light steel sections are not dip coated, but electro plated, with the end coating being significantly thinner, and so less durable than, dip coated steel, and that the thinner the steel itself, the thinner the zinc coating will be.

So, given all of that, I'd be very inclined to seek out and check any exposed parts of that galvanised space frame for corrosion. 

However, having said all that, I'd expect the front end of your Hymer to be based on a standard Fiat Ducato "chassis cowl" (in effect the complete engine and transmission with cab floor and inner wings, but minus any other bodywork, terminating just behind the front seats, with the space frame element (maybe supplied by AlKo) bolted on to that to provide the underpinnings for the motorhome bodywork and habitation equipment.

[Derek Uzzell]

These links concentrate on 'classic' Hymers.

https://classichymers.co.uk/

https://www.facebook.com/groups/classichymers/