smplybttr

Aloha,

I have a 95 5.0 that needs a new water pump. I got the old pump and thermostat off, but not without breaking one bolt on each. I use this Maui Cruiser as a daily work truck, so it's causing me problems in its current state. I have a 90 Toyota FJ62, so I'm used to wrenching, but these bolts are taunting me in a way that is questioning my existence.

I have snapped off ten different bits of different materials and sizes. I bought a hammer drill to help. I've PB blasted the hell out of them. I've MAPP blasted them and used vice grips. The bits are only digging in about 1/8", which isn't enough for the easy outs to bite, and then the bits round over and smooth out the hole.

Since I don't know this engine well, yet, I have a few questions. (I did search for broken bolts, but no real responses popped up.)

-What the hell are these bolts made of? I've never had such a hard time with the Land Cruiser.

-Since one bolt is in the water pump mating plate, I thought about pulling it off, but didn't know what was behind it. Does it also serve as the timing cover? If I pull it, what gasket(s) need to be replaced?

-Do I have to pull everything above the manifold to get to the thermostat neck? If so, how big of a job is it on this truck?

-I did see one post where someone mentioned a diamond tipped bit. Any information on these? I do bathroom remodeling, so I'm familiar with the type that are used for that, but haven't had the need for one to use on metal.

-In that same thread, someone mentioned that the 5.0 is known for breaking bolts. If this is true, are there any tricks to which ones and how to limit breakage?

Thanks in advance,
Terry