The floating bonnet thing
The floating bonnet thing
Author
Discussion

mars

Original Poster:

10,107 posts

243 months

Friday 9th February 2007
quotequote all
Yes, I know TADTS but I was wondering if they do it for an *intended* reason. If not, and it's just the case of poor development, I wondered whether I should replace the two (now missing) rubber stops under the centre of the bonnet, where it rests on the battery cover, with some of those cheesy rally bonnet clips. I hate things like that but I'm seeking a solution because all th floating is causing the bonnet to rub the paintwork.

Anything available that's less conspicuous?

southendpier

6,208 posts

258 months

Friday 9th February 2007
quotequote all
mars said:
cheesy rally bonnet clips.


no no no! Must be something else - no! Beautiful line of the bonnet should not be destroyed by anything IMHO.

When you mean "floating" do you mean a little movement like a vibration or is it lifting? Vibration - surely you can deal with that but I thought that lifting is caused by a small flap - can't remember the name - under the front of the car, that sometimes is missing. The flap is used to cause airflow pressure to suck the bonnet down under speed.


Aerofoil

1,543 posts

266 months

Friday 9th February 2007
quotequote all
If the rubber rests are positioned correctly and the rods are not wobbly, then the bonnet should not move. (well maybe a little, but not up and down)

ridds

8,372 posts

273 months

Friday 9th February 2007
quotequote all
Anyone know where to get the plastic lugs that go on the end of the bonnet lock rods?

Mine are well worn.

mars

Original Poster:

10,107 posts

243 months

Friday 9th February 2007
quotequote all
Definitely floats. Rises quite a bit at speed.

It hasn't got the air deflector in the front though. Should I get one? I hadn't realised it does anything useful.

c3ber

4,714 posts

252 months

Friday 9th February 2007
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I find if it stops floating the faster you go. To be honest its not bothered me.

trackcar

6,453 posts

255 months

Friday 9th February 2007
quotequote all
I cant remember your car doing anything unusual before, so are teh bonnet rods locating properly in the bonnet catch holes? it's sometimes the case that the bonnet needs pushing down so the rod lines with the hole ..

mars

Original Poster:

10,107 posts

243 months

Friday 9th February 2007
quotequote all
Oh yes, the bonnet rods are working. I always give the bonnet a little "test" upon relocking.

The main area that is rising is the middle of each side. I can see that the chamfered area there indicates TVR engineered the bonnet to act as a vent but the lift is just a little alarming. My idea of centre catches at the windscreen-end was simply to take the strain off the bonnet rods, although Jules did mention you had already made some improvements to the original design so this might be irrelevant. The rubber stand-offs/feet/stoppers/whatever you call them are worn away to nothing, indicating fretting so it seems the most suitable point to engineer a second locking mechanism, although having thought about that, I imagine that will simply transfer the upward loading to the battery cover. I have (currently) no idea how well that's fixed to the car.

Worry about nothing?

jbvipercerb

246 posts

249 months

Friday 9th February 2007
quotequote all
I recently adjusted the bonnet catches because it was quite tight to lock but the bonnet still lifted a bit at speed. Eventually I put a small piece of rubber pipe around the knob's stop bolt, in the car. when the knob was turned, to lock the bonnet, it went tight then went over centre and slackened the bonnet off. The pipe just stopped it going too far over centre, just enough so it stays locked.

mars

Original Poster:

10,107 posts

243 months

Friday 9th February 2007
quotequote all
I'm confident my bonnet rods are working well. There's an over-centre feeling to it and a little bolt sticking out stopping it at both extremes. Also, I remember jules telling me that Joolz had adjusted them/made them better.

Cyclone1

2,614 posts

275 months

Friday 9th February 2007
quotequote all
FFS don't do the cheesy rally thing!!

You need to replace the rubber seals on the brackets that the rods locate to, these were about u/s before I sold it to you. With these in place you should get the rods locating firmly and the bonnet shouldn't lift. If it still lifts after you have done this, then replace the two rubber bungs in the centre that the bonnet should rest on.

If you remove the cover under the windscreen / battery then make sure you put it back correctly, as if you don't then this can prevent the rods from locating correctly.

I have a wind deflector but never fitted it as I never needed to. If you want I can post it to you?

Jules.

GreenV8S

31,017 posts

313 months

Friday 9th February 2007
quotequote all
I don't know if this applies to the cerbera, but on my V8S the bonnet used to rattle a little at speed, this stopped when I got the bonnet vents. Is it possible that some innocuous change to the ride height, attitude, front splitter etc has subtly changed the air pressure disribution and caused the effect you're seeing?

Cyclone1

2,614 posts

275 months

Friday 9th February 2007
quotequote all
Forgot to add that if you can't replace the central rubber bungs then you can do what I did on my old 4.2, which was to clean up the area where the bungs are and put a piece of sticky back pad (about 5.8mm thick with a soft carpet type finish that you can buy from hardware shops etc) on for the bonnet to rest on, this will take out the play from where the bonnet rests on the centre section.

I reckon that once you have replaced the rubber seals on the brackets where the rods locate then you'll be fine.

Jules.

mars

Original Poster:

10,107 posts

243 months

Friday 9th February 2007
quotequote all
The cheesy rally locks were only an example really of where I thought additional locking might be useful. I'm not about to drill the bonnet for those or additional vents, or anything else [shudder].

I've temporarily stuck a very thick number plate sticky-foam thingy where those centre stops should be and that hasn't made much difference. I'll have a look at the ones at each corner. I've missed those. The bonnet's quite stiff for a minimally-supported fibreglass structure so it could be just the thing.

I read about someone else having had a problem with the hinges, so I checked them and they're absolutely fine.

TooTall Paul

938 posts

276 months

Friday 9th February 2007
quotequote all
Mars have you got the little spoiler attached, that helps with bonnet movement.

mxi933

467 posts

237 months

Friday 9th February 2007
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I know when I picked up the purple one the bonnet was wobbly.
The front hinge had come away from its fibre glass mount and the two rubber grommet thingies were missing.
I whipped off the bonnet and repaired the hinge mount and picked up a pack of sticky backed rubber bung things from B&Q.
The bonnet is now very snug indeed

mars

Original Poster:

10,107 posts

243 months

Friday 9th February 2007
quotequote all
TooTall Paul said:
Mars have you got the little spoiler attached, that helps with bonnet movement.
I haven't but I'm concerned that it diverts air flow away from the rads. Perhaps I had better take a look at one before I comment on it further.

Anyway, I'm going to go with Jules' advice to get the rubber feet/stoppers/things replaced first and I'll see how that goes.

TooTall Paul

938 posts

276 months

Friday 9th February 2007
quotequote all
I have pipes under the indicators flowing air onto the disks, maybe an idea!

Cyclone1

2,614 posts

275 months

Friday 9th February 2007
quotequote all
mars said:
TooTall Paul said:
Mars have you got the little spoiler attached, that helps with bonnet movement.
I haven't but I'm concerned that it diverts air flow away from the rads. Perhaps I had better take a look at one before I comment on it further.



I think that Paul means the spoiler that fits under the nose of the car, this shouldn't divert air away from the rads. The air scoop that feeds the air filter *is* removed from the car and this allows more cooling to the rad but does not detract from the amount of air going into the air filter box.

I have a spare spoiler / wind deflector in the garage if you want to give it a go.

Jules.

mars

Original Poster:

10,107 posts

243 months

Friday 9th February 2007
quotequote all
Thanks. I'll give the rubber feet a go first and if that doesn't work I'll give you a shout.