I wonder if anyone can help me with this problem - though it is relating to a 390, it is in a 63 T-Bird, not a truck.

This is my first repair on this car and I am foolishly flying without a manual. I took out the radiator and sent it out to be re-cored, and then I took out the water pump not realizing that there are two different bolt sizes - and now I don't know which goes where. On top of that, the flange on the replacement pump is an eighth inch thinner than the old one. To avoid having the bolts bottom out in the block, do I need to get shorter bolts? And then which ones go where? Any help would be appreciated. Thanks

 

Wow........I never knew there were different length bolts? Guess I never had stock motor apart? Stick the bolts thru pump, measure or mark the length sticking out the back and then screw them into block to mark by hand. There should be plenty of area in block, but check to be sure and just don't crank down on them with wrench. Nothing a regular old flat washer can't fix.

It's not a big deal, really. Don't sweat it.

 

While your at it, with a freshly cored radiator on the way. You may want to leave the top hose to the radiator diconnected for a few minutes, put a water hose in the fill and run her at about 2500 rpm to get as much junk out of the block as possible before letting it start using the new radiator.

 

yeah, my block had a hole bottomed out when i replaced my pump. i think it was the top left bolt hole when facing the front of engine. but, as Freightrain said, measure it before tightening down or you will be putting that bolt into the water jacket and into side of cylinder wall.

 

When ya put the new pump on. Put gasket sealer on the pump side only. This makes it easier to replace and clean up the next time. And or tie the gaskets in place with thread. Leave the thread as it won't hurt a thing. I prefer not to use any gasket sealer with new parts and gaskets. Expect in certain applications.

 

Thanks for the tips. I thought of the added washers after I posted. Should do the trick. Still wondering about the "why" of the different bolt lengths - a longer and shorter one from each side. Yes, definitely planning to flush it out before putting it all back together.

 

right bank of cylinders are shorter distance to front of block. shorter bolts where they would go into the water passage.