close quarters 90 degree drill head needed

[mike90045]

 So, I guess 3/8" bolts are insufficient to anchor my frame to the other frame.  While they lasted 50 hours, the replacement lasted 5 minutes.   To avoid having to pull the engine off it's frame, and then take the lower frame out and drill the I beams from their backsides, I'm looking for some some sort of drill, chuck, gearhead, 90deg air drive drill motor, something, that I can drill in place, up to 7/16" .   The rail width on the I beam is not large enough to get 1/2" bolts in, but I think 7/16 would do it.   

Any opinions if 3/8" is too small to hold the load, did I get a couple of duds ?   Would 7/16 be enough   to hold the frame (not the crankcase) of a 6/1

[dieselgman]

I generally use 1/2" fasteners for the smaller engines, and upwards from there.
Milwaukee makes a nice offset drill motor with 1/2" chuck.

dieselgman

[mobile_bob]

i have seen these angle drills at many pawn shops, they generally always work and can be bought reasonably...  never pay the sticker price, dicker with them and you can usually get around 30-40% off the listed price.

failing that, harbor freight sells some smaller angle drills, however the are limited to 3/8 inch

they also sell a three piece step bit set, the smallest of which is 1/2inch on the largest step

these bits really work well, just keep them cool with a dribble of water and the drill right through.

great for enlarging holes

good luck
bob g