Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Windscreen frame securing brackets 1986

Hello everyone.

Does anyone know the thread type of the small screws which hold the lower frame bar to the upper section, using the angle brackets? I have broken some (rusted in) and need to drill and tap them again. The thread outside diameter is 3.5mm. There is a thread test board at the local hardware shop but not for small sizes.

It might be UNF or even BA. I could take them out to 4mm metric but would prefer to keep the same size if it can be identified.

Can only add they are metric M4 screws on later models. Be careful to check length though as some are shorter than others. Be even more careful if re-tapping. In either case contact with the glass can cause shattering!

Note M3.5 screws exist so worth a check. 5BA has major diameter of 3.2mm and 4BA 3.6mm if it helps.

Neil--I have a 1986 +4 Fiat twin cam. Mine appear to be Metric M4 as pointed out by Richard. I have owned since new so the screws have never been changed. Suggest replace with stainless and maybe add a little anti-seize when replacing.

TomS - I have new brackets (complete with screws) from Melvyn Rutter so I just need to fit them. The old rusty ones can be discarded. As a matter of interest the threads are 2BA (one screw) and 4BA (three screws).