Securing the bonnet

[davidball]

Do later Caterhams have bonnet locks? My 1987 car does not. Is there any way of securing the bonnet apart from straps and padlocks!

[Aeroscreens]

David,

Don't worry you're not missing out on anything. All Caterham's still have just the bonnets springs at the front and latches at the rear of the bonnet.

I've not heard of anyone 'locking' their bonnets and it doesn't seem to be a problem.

Is there some reason why you feel the need to lock it?

[davidball]

For a couple of weeks I need to use the Caterham to commute to my local train station where it will be parked all day. I fitted a battery cutoff switch for the usual reason but also as an imobiliser. However, if you can remove the bonnet you can bypass the cutoff.

[fergus]

just remove the coil end of the HT lead and leave it dangling, or pull the fuel for the fuel pump, or just dislodge the connector on the MFRU which will disable all the relays....

[davidball]

Thanks for your help but, if you can get under the bonnet you can simply reconnect these and have it away with the car. What is an MFRU?

[fergus]

davidball said:

Thanks for your help but, if you can get under the bonnet you can simply reconnect these and have it away with the car. What is an MFRU?

MFRU = Caterham term for the Multi Function Relay Unit (small black box looks a bit like the std ECU).

Yes you could reconnect them, but you'd need to know what you were looking at, and also you'd only just dislodge the connectors, rather than leave the plug dangling!

You could also place a switch up under the dash which killed the fuel pump supply. This would be hard to find for a casual thief (without a multimeter!) and would also mean you wouldn't have to remove the bonnet. Even better to wire this into a switch on the dash you don't use all the time?

[P.Nott]

If its a 1987 car I suspect it might be a crossflow so therefore will not have an MFRU and probably hasn't even got an electric fuel pump that can be isolated with a switch. A removable steering wheel is always a good idea for thwarting theft.

[davidball]

You are correct. A Xflow it is. Next weekend I intend, purely as an academic exersize, to look at ways of securing the bonnet. If it is possible, without too much hassle, I will post photos.

Edited by davidball on Tuesday 10th March 08:48

Edited by davidball on Tuesday 10th March 08:49

[P.Nott]

Have you looked at the Car Builder Solutions website? I could be wrong but I'm sure I recall seeing a lockable toggle type fastener that can be used for this application.

When I owned a Caterham I didn't have any problems with people lifting the engine cover but as I said previously I had a removable steering wheel which whilst it can be a pita to carry around with you I think it does reduce the likelihood of some scrote nicking the car.

The usual way to foil any attempt at theft on a crossflow is to remove the rotor arm but again that is a pita and a dirty job to do on a Caterham if you are suited and booted as the distributor is buried under the forward carburettor. I would go for a concealed switch and wiring that isolates the low tension side of the coil but near the distributor. Yes it will still be possible to bypass this from the battery but it should fool a prospective thief long enough to put them off.

[davidball]

Thanks for the info. I will check the website out.

[Aeroscreens]

You could also consider just buying a suitably large 'D' lock that fits through the front wheel and through the front suspension.

[Murph7355]

If you lock it, should a ne'er-do-well start fiddling with your car they'll want in even more. And it's only ali.

If your prime concern is preventing theft, a removable steering wheel is a good option. You could also take the HT lead with you to work.

[davidball]

It is about a mornings work fit locks to the bonnet.

Securing the front of the bonnet is quite easy. Drill a hole in the rear face of the brackets that house the Dzus fasteners for the nosecone. Fit a bolt of suitable length.

http://img262.imageshack.us/img262/9895/imag0086.j...

The flange on the bottom edge of the bonnet slides beneath the bolt. The front of the bonnet cannot be lifted up when in place and the small lip (arrowed) on the flange stops the bonnet from being pulled sideways past the bolt.

http://img255.imageshack.us/img255/6632/imag0087.j...

Securing the bonnet at the windscreen end is not so easy. You need to make a template so you know where to drill the holes for the locks in the bonnet.
I used the clear plastic from an audio cassette case so I could see better.

http://img11.imageshack.us/img11/9819/imag0093.jpg

You can see from the photo I had a couple of tries to get the position right. Once done I noted the measurements from the bonnet edges (the edge nearest to the windscreen and the bottom edge). I did the passenger side first because it was easiest to get at.

I used a mild steel right angle shelf bracket for the catch, bent into a z shape as shown.

http://img10.imageshack.us/img10/4162/imag0094.jpg

The lock lever engages through the hole in the bracket preventing the bonnet from being lifted up or pulled sideways. Attempts to push the bonnet forward to disengage the lock lever from the hole in the bracket fail because the bottom flanges of the bonnet butt up against the Dzus brackets.

Do not use the type of locks that have a retaining clip like I did. It is much better to use the locks that have a threaded barrel and nut to retain them