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MG MGB Technical - Installing Bonnet Thimble

I have to re-install my bonnet thimble and I cannot figure out a method to hold the spring compressed whilst threading the thimble into the bonnet fitting. My "squeeze" capability is not up to the task. Is there something I am doing (or trying to do) wrong? The thimble does thread in with the spring between the round plate and the bonnet itself, right?
DW
J.D.P. Wall

As I remember it, HTH.

The thimble is dropped to the bottom of the pin (cone at bottom) so that the thimble sits on the top of the pin cone.

A locknut is threaded down the pin.

The spring sits on top of the thimble with the pin in the middle of the spring.

The pin cone has a (wide) screwdriver slot to use a larger sized screwdriver to screw the pin (cone) into the bonnet. The lock nut locks against the bonnet to hold the pin position.

I can't remember that there's much resistance in the spring at the start of screwing it in, but you could compress the spring with the use of three suitable cable-ties on the middle section to get the pin well located into the bonnet.

Once you have worked out roughly the correct locking length of the pin cone you can cut off the cable-ties and use the lever of a slim spanner or screwdriver shaft to relive the spring tension for final fit adjustments.

IIRC finding the right tool to lock off the the lock nut can be a bit of a pain because it needs to be slim enough to get between the spring's coils.

Make sure you have access to the catchplate or its cable in case you set things too tight with the bonnet catch and it causes it not to open from pulling the cable from inside the cabin (allow for needed rebound on bonnet shutting).

It's harder to describe the job than actually to do the job, though the job can be a little awkward it's not difficult otherwise I'd not be able to do it.

Cleaning the threads on the pin and using coppergrease will help with adjustment.
Nigel Atkins

The pin goes through the thimble, the spring, and a lock-nut into the bonnet.

If the spring is freshly painted then cable-ties as said is probably the way to go. Through the first and last gaps each side rather than round the whole spring,
maybe compressing it in a vice to fit them.

If not bothered about damage to the finish then grips of various kinds to compress the spring.
paulh4

My thanks to Nigel & Paul. I had tried one cable-tie with no success but encouraged by the replies I went at it again, managed to get two ties on the spring and then it was a cinch to thread the bolt.
Great source of assistance here.
David
David Wall

Well done.

One cable-tie can make things lop-sided and slide round on the spiral so at least two is best plus less likelihood of one breaking. Three I think makes it easier to even out the tension around the spring spirals and as our Irish friends say "to be sure, to be sure".

Don't forget to lubricate pin cone, cup and cable.

Paint on the spring made me smile, you can get a whole kit in stainless steel if you want to go bling.
Nigel Atkins

I use 2 cable ties. Works well.

Colin
Colin Parkinson

This thread was discussed between 18/06/2019 and 19/06/2019

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