Breezy Bonnet Syndrome

[jbcollier]

After a couple of short trips, and fettling the few final issues after a major refresh, I went for a proper 700 km round trip.  Overall it went very well.  Economy is not as good as my Europa but reasonable none the less.  Suspension is as good as can be expected with the rear being quite firm on the big bumps.  I did some experimenting and buffeting can be reduced to reasonable levels by either shrinking an inch or so, or by adding a small clip-on extension to the door frame.

All well and good.

However, I was alarmed to find that three of my bonnet latches “weren’t” upon arrival.  They all stayed latched on the return journey but I’m afraid my confidence has been shaken.  It’s a somewhat original 69 Seven S3 and I’m trying not to stray too far from stock.

Any suggestions on how to keep the bonnet firmly in place while I further push back the Seven’s horizons?

[Jonathan Kay]

What foam or rubber do you have between the surfaces?

There's some discussion in the archives of better latches, and possibly of fettling.

Jonathan

[OldAndrewE]

I take it you have four over centre clips as originally fitted to sevens.  I had the same issue with an S2 I has some time ago (the bonnet once went backwards over my head).  If you are not concerned about originality then I suggest fitting the spring latches to the front as current Caterhams and do what you can to make sure the rears have decent tension on them

[jbcollier]

Yes, original latches.  Good suggestions, thanks.  I'll start with replacing/adding foam gasketing to give the latches more tension.

[David Mirylees]

I have been using the lockable over-centre latches on my S3 since the early 80's. They don't come undone so playtime can be enjoyed without worry.   (I went through many adventures particularly with the rear latches become undone).
I obtained my latches from a company called Protex - I assume they still exist as they were/are a large supplier to the engineering industry.  They also fit the original mounting holes (well, at least mine did!)
I just use 'R' pins to secure them.

David

[7 wonders of the world]

If theres any wear or play in the main latch pivot it will reduce the over centre effect

 

[Jonathan Kay]

"I obtained my latches from a company called Protex - I assume they still exist as they were/are a large supplier to the engineering industry.  They also fit the original mounting holes (well, at least mine did!)"

IIRC the last time we couldn't find any that did. Well done.

Which model, please? https://protex.com

Thanks

Jonathan

[David Mirylees]

I couldn't immediately see the model of Protex over-centre lockable latch (they are appx. 40 years old!) but a search on Google and a look at the images threw up a number of possibilities and these looked about right but I didn't see any size mentioned.
https://www.demon-tweeks.com/grayston-over-centre-panel-clips-243649/?sku=GRYGE65&istCompanyId=a2904180-3a7d-4e56-b876-cf81c9512180&istFeedId=6fbc4b04-fd28-4ce1-8513-835c8f118690&istItemId=wptwlxamr&istBid=t&gclid=Cj0KCQjwusunBhCYARIsAFBsUP8h-r-PJfgpiRt9QRwgq9PYZiIznBAEt12Zrlq_F6ck1FfDX_7Owl0aAnGmEALw_wcB&gclsrc=aw.ds

david