Vic787 Posted July 3, 2021 Report Share Posted July 3, 2021 Does anyone have under bonnet insulation to combat vibration noise. If so any recommendations. Quote Link to post Share on other sites
stuart Posted July 6, 2021 Report Share Posted July 6, 2021 Your better off insulating the firewall and gearbox cover, any underbonnet insulation is 1 difficult to fix properly and 2 often looks rubbish. Unlike moderns where they have specially shaped sections buttoned up to the underbonnet Stuart. Quote Link to post Share on other sites
Vic787 Posted July 10, 2021 Author Report Share Posted July 10, 2021 Hi Stuart I was just looking for ideas, It is the sound resonance on the bonnet which was troubling me, particularly on tick over. I thought it was a daft question, Some things I have to put up with or do away with it all together, No way. Thanks, I agree, don’t want anything ugly under the bonnet. Quote Link to post Share on other sites
signalredshaker Posted July 10, 2021 Report Share Posted July 10, 2021 The engine area is best dealt with from inside the car- closed-cell foam is very effective when fitted to the bulkhead - its adhesive on one side and available in various thicknesses- I used around 12mm thick. Its quite a job as wiring, piping and all sorts get in the way but worth it after a massive fiddly job. Try:- https://www.deadening.co.uk/collections/ccf-closed-cell-foam The same team sell sound damping pads for floor, metal panels etc. Dynamat is one brand. James Quote Link to post Share on other sites
keith1948 Posted July 10, 2021 Report Share Posted July 10, 2021 Make sure the 2 cone shaped rubber pieces that fit into the 'dimples' at the 2 corners of the bonnet at the windscreen end of the bonnet are correctly located and adjusted so they touch the bonnet. Up and down adjustment is achieved by the screw that connects them to the car. You can put washers as spacers to get the correct height. Once you have the height correct then with the nut slack, close the bonnet and open again. The cones should now have moved in line with the dimples in the bonnet. Tighten the nuts and then they should stop that end of the bonnet vibrating/squeaking. There are also rubber wedges along the drain channels that can be adjusted to fit. On mine there is also something best described as wadding that is between the bracer and the bonnet underside roughly beneath where the Triumph letters fit. Keith Quote Link to post Share on other sites
stuart Posted July 11, 2021 Report Share Posted July 11, 2021 16 hours ago, keith1948 said: Make sure the 2 cone shaped rubber pieces that fit into the 'dimples' at the 2 corners of the bonnet at the windscreen end of the bonnet are correctly located and adjusted so they touch the bonnet. Up and down adjustment is achieved by the screw that connects them to the car. You can put washers as spacers to get the correct height. Once you have the height correct then with the nut slack, close the bonnet and open again. The cones should now have moved in line with the dimples in the bonnet. Tighten the nuts and then they should stop that end of the bonnet vibrating/squeaking. There are also rubber wedges along the drain channels that can be adjusted to fit. On mine there is also something best described as wadding that is between the bracer and the bonnet underside roughly beneath where the Triumph letters fit. Keith TR4 didnt have the pointed cones at the rear of the bonnet they only had flat topped bump rubbers though accurate adjustment of them plus replacement of the side wedges do help. Stuart. Quote Link to post Share on other sites
qkingston Posted July 15, 2021 Report Share Posted July 15, 2021 My early 4a (mar 65 - 52373) had flat bump stops and no bonnet dimples, both believed originals Rgds David Quote Link to post Share on other sites
Vic787 Posted September 7, 2021 Author Report Share Posted September 7, 2021 Following above advice, checked bump stops and remember when I rebuilt the car 35 years ago I cut the tops off the cone stops leaving them flat, I have adjusted them and cancelled all vibration. Ahhhh silence, can now hear the delightful exhaust. Thanks all Vic Quote Link to post Share on other sites
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.