Chicagoland MG Club
Attaching MGB Seats to the body floor
Everyone who has re-fitted seats in a MGB has been frustrated by how "fiddly" it is to get the bolts in. Fate intervened when a friend managed to strip the bolt holes. After removing the seats, I installed 1/4 x 28 heli-coils in only two of the holes, and installation was a breeze. There is no reason for half the bolts on a MGB to be coaese thread. Certainly not seat bolts.
I suggest that instead of drilling through the floor pan and using nuts (a two person job) that investing $20 for a helicoil kit saves back ache and time and frustration. Also drilling through the floor pan introduces potential for rust and other issues. In short, having a 17/64 bit, and some helicoils helps - the kit has the installation handle which is well worth the expense. I installed a seat in 20 minutes! Tapping the hole is short and simple.
My seats in my 1972 MGB GT are now solid - versus my 1970 MGB GT where someone drilled the pan, and the nuts were rusted - what a pain! All I need to do to fix that is some more 1/4" x 28 helicoils, since I have the installation tool - and a bit and the tap.
I think the notion of drilling through the full floor just to use any bolts from the local hardware store is not a "best solution". Just drill and tap for a fine thread bolt - 1/4 X 28 thread, and they will spend less time with installing the seats.
Find additional information on installing Helicoil thread inserts at www.mgaguru.com/mgtech/universal/ut105.htm
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