Flapping Bonnet

[lateconvert]

At press-on speeds the nearside edge of my bonnet (particularly the corner nearest the windscreen) flaps around alarmingly. I had to give up a maximum speed run going down to Classic Le Mans because my passenger thought the bonnet was going to rip itself off.
Is it a case of 'they all do that sir' ?
Anyone seen or heard of anyone fitting a secondary catch ?

[simon818]

Well, this is interesting bacause that happened on my test drive at HHC. Only a small fluctuation of the corner near the windscreen though but I was assured when it had been serviced that it wasn't a problem. I must admit it sometimes gets on my wires but there's no danger of the hood lifting, the wind sees to that.

Anyone got a cure??

[tonto]

I had a similar problem. It turned out to be the hinge bolts coming loose. They are set into a fibreglass panel which is glued to the front of the bonnet. The solution is to either get a new panel fitted (which comes with the bolts) or do what I did, which was to add some fibreglass matting around the bolts. This cured the problem. I don't get any bonnet movement anywhere now.
The acid test to check if you have hinge problems is to put your hand under the front of the bonnet, (with it down) and try and lift it. If it moves at all then the hinge bolts are loose. BTW, when you lift the bonnet, any side to side movement is normal.

[magnus]

lateconvert said:

At press-on speeds the nearside edge of my bonnet (particularly the corner nearest the windscreen) flaps around alarmingly. I had to give up a maximum speed run going down to Classic Le Mans because my passenger thought the bonnet was going to rip itself off. Is it a case of 'they all do that sir' ? Anyone seen or heard of anyone fitting a secondary catch ?

You don't say how old your car is or the mileage. I had this problem which was caused by wear on the bonnet catch--replacement was complete solution.

[m808clr]

I had a similar prolem with my bonnet and even after working on the hinges, the bonnet continued to vibrate and lift. I then discovered that on either side of the engine bay are two nylon off-center rollers that can be adjusted to put tension on the bonnet when closed. I don't know whether all cars are fitted with these but with a slight tweek they cured the problem.

[lateconvert]

Thanks for the input

Tonto - good call, my hinges are loose so I will be trying that first.

M808clr - I didn't realise those rollers were adjustable so will look at those too.

[victormeldrew]

The rollers do wear, the bonnet will cut a groove into them, so they do need adjustment from time to time to keep the tension.

As with many things, if this is not done then the flapping around will lead to premature wear on the hinges - which really shouldn't "wear" at all, as there should be no movement!

[Voltaire53]

lateconvert said:

Is it a case of 'they all do that sir' ?

AIUI the early Chims (before the Cerbera-like front end) can have problems with pressure opening the bonnet at speed if the catch fails (which it can) but the later ones don't have the same problem.

I may be wrong though!