The Stovebolt Site Forums The Shop Area Engine Shop Welding studs onto water pump adaptor plate?

My dad is working on our motor for our 3/4 ton, 1953 chevy. We are rebuilding a 235 and we have the adaptor plate to mount the water pump from the 216 onto the 235. My dad's concern is that he doesn't want to drill into the block for those top two holes of the adaptor plate (someone correct me if those aren't the two holes you have to drill!). He says there's a space between the plate and the block where those top two holes are (does that sound right?) and what he's wondering is: Has anyone ever considered welding studs to the plate where the top two holes are instead of drilling and tapping the block? Doable?

Really bad idea- - - -unless the pump is secured to the block at the top, the plate will bend and leak from the tension of the fan belt.
Jerry

Jerry,
Is it advisable to create bushing/ spacer to place between the plate and block that the bolt can run through? I wondered too about this gap.
Paul, I used this plate and tapped the block. Went fairly well, go slow and you'll be fine. If you have a scrap block you could do a practice run.

I have installed close to 50 of these and have never used any spacers between the plate and block. I find it unnecessary.

All of the force applied to the top bolts is in the outward direction, away from the block due to the tension caused by the stretch in the fan belt. No spacers needed.
Carl

Ok, I know this sounds argumentative, but I really don't mean it that way. Those that say it's not a good idea, has anyone actually ever tried it? I have a lot of money in this block, it's been machined for bearing guides and it's all to spec. If something happened, I don't know if I'd have the cash to do it over anytime soon. My dad has been a mechanic his whole life, but mostly on construction equipment (he started as an airplane mechanic). As anyone who does that work knows, you have to be very good at figuring out how to make something work with what you've got. You can't just go get new parts all the time when you're in the field. My dad was very good at his job, so I just want to make sure I give him as much information as I can.

For the benefit of the folks who are reluctant to freehand the block drilling procedure, I'm considering fabricating a drill/tap jig for the spacer plate installation similar to the ones I rent/sell for threading a crankshaft snout. The jig would bolt onto the block and use hardened steel drill guide bushings to position the holes accurately.
Jerry

Absolutely no problemo installing the adapter plate as per instructions that came with. Done it on my personally rebuilt 61-261 and everything is just fine.

If the guy who invented the plate has installed almost 50... Well, Grigg and I did my 261 block and I helped as he drilled by holding a 90 degree block to ensure drilling the hole straight in on one plane as he freehand drilled the holes. Much easier to do with 2 people, although Jerry's drill/tap jig is a fine idea if you have severe doubts in your ability or you are doing the work alone.