Engine mount bracket...Bolt broken in engine block (2003 Protege5)

[Insouciance]

Hey all,

Hopefully this place isn't dead like the rest of the Protege forums.

Just finishing up timing belt job on wife's 03 P5. When taking everything apart I removed the engine mount on the front of the engine there, but also the bracket connecting to engine block to give myself more room, which was probably a bad idea in retrospect.

My Haynes manual says 55-75 ft-lbs torque for the 3 bolts from the bracket to the engine block. So I am torquing away, switching between them. First one got a click, second one, the head of the bolt and first half inch of threads ripped right off.

Why does Mazda use Grade 8 steel??? It's funny I was just looking to see if some replacement bolts I had for something else were good enough being 10.6 steel and found a comment saying to replace Mazdas bolts for some things.

Well. I am hoping that bracket will hold okay with 2 of 3 bolts... Any thoughts? I have no clue where I would even start to get that damn bolt out.

 

[TheMAN]

Your biggest mistake was using the Haynes manual to begin with. Those are worse than toilet paper. Use the real shop manual which has been floating around on the internet for the past 20 years, and mentioned often here.

The bracket's bolts are supposed to be only torqued to 32 to 44ft lbs, and they're not "grade 8 steel"... they're CLASS 8, which is a completely different thing in metric... regardless, that "55-75ft-lbs" isn't mentioned anywhere in the shop manual, and I can only assume it's talking about the 3 NUTS that goes from the motor mount to the 3 studs on the bracket, as the actual spec is 55 to 77.3ft lbs... and when there's a lack of information, such as the bracket's bolts torque spec not being in the shop manual but the separate engine overhaul manual, "good 'n tight" is the way to go and less risky

The engine is not designed to be supported by 2 bolts, so remove the bracket and see if there's enough of the broken bolt to twist out by hand. Otherwise, you're going to have to carefully drill it out using extractors. You might even have to get the car towed to a shop so they can do it for you