We are rebuilding a 400 for the 67 Sportwagon conversion to a GS 400 clone. In putting on the water pump with new bolts the two 3"+ long bolts on the drivers side of the pump felt loose and not tight fitting even before we started the pump installation. When all bolts were installed and were torqued to 23# per service manual chart (low value, chart also said 25#). All bolts except the long bolts tightened to 23# OK but the long bolts while tightened to 23# could be tightened further. We are concerned we are about to strip the threads out of the block if we go tighter. Any experience or advice here? Thanks in advance for your comments or advice/experience
You won't pull the treads out, the bolt would break first, and just because it will go tighter doesn't mean you should, kinda like an oil pan gasket if you tighten till it stops you will destroy the seal and the gasket, just tighten them evenly till they seat then go another full turn or so or the 23lbs
I've never used a torque wrench on the water pump bolts. I use a 1/4 drive ratchet. The issue with a 1/2 drive torque wrench is the bolts for the pump are pretty damn small for a 1/2 drive ratchet, and it doesn't feel tight, so you wanna go more "doesn't feel tight" you can EASILY snap them bolts going tighter, like Hugger said
Personally, I make them just a little tighter than snug. I do it by feel mainly. Basically the same torque you would apply to the thermostat bolts. And you probably don't even give those a second thought at all when you sock them down
I have had to helicoil those bolt holes in the block before due to a rusty bolt causing the threads in the block to rust and weaken, it was easy and gave me some peace of mind.
