Hello, '94 348 Spider. Does anyone out there have experience removing the drain plugs (one either side) on this block for draining the antifreeze coolant in a service / coolant change/flush? Mine are turning out to be REAL buggers. First, they are barely accessible (engine in) and mine appear to be made of some sort of brass or yellow metal alloy (bronze?), definitely NOT aluminum like the block itself, and NOT steel or duplex steel. Mine are also 6 mm Allen key. Both appear to be stripped from previous attempts to remove them before I owned the car. I have seen other photos showing BOLT heads instead of Allen key type. Bolt heads definitely would be better...but I suspect mine are OEM and Allen key type. Any suggestions as to replacement if I can actually get them out? Both are so tightly bound, that 6 mm Allen keys have stripped out already. It looks as if I could pound in a 1/4 inch hex bit and try to remove by wrenching them out with a 1/4 flare wrench. Would gentle heat (propane) around the aluminum bosses help? Any other ideas? Access is really tight and I am NOT going to remove exhaust manifolds to gain better access, or try Ezze-outs or other types of screw extractors. they is NO ROOM for that in any case. Should I even try?..or wait until I do the next engine out major service and repair these drain plugs properly. Can the engine drain/flush be accomplished anyway, with multiple dilutions of distilled water before adding fresh antifreeze (Zerex G 05)? Any guidance is greatly appreciated. marbroman
^ Agreed. My 355 has 6mm plugs. Taking a few measurements, a 1/4 bit is so much bigger I would be surprised if you could get it smashed in deep enough to matter. If so you may have forced the threads outward enough to make it tighter? IMO, considering the 6mm hex is stripped, the way I would approach it is a chisel, manual or air hammer grabbing the outer diameter of the plug. Much more leverage than anything you will do internally now. That being said, overall I would not sweat it. Drain/replace the coolant otherwise and let it roll.
They are brass construction. Yes, heat will help when the time comes, but if they are previously damaged it's probably best left until an engine out, drilling and an extractor will probably be required.
Thanks for all the guidance fellas. I think they will stay in place until I pull the engine for the next major service. marbroman
Mine came right out both sides with impact gun and impact socket. Sent from my SM-G990U using FerrariChat.com mobile app
50 % of the times, those buggers strip and don't come out for me. It would take a drill bit, an ezout before it comes out. I frankly don't understand the low quality of the brass plug.
