Hi,
I’m going to be replacing the radiator on a 1993 Caprice (plus hoses, radiator cap, thermostat). I was debating replacing the water pump while I’m at it or leaving well enough alone. I’m concerned about breaking any of the attachment bolts. The only water pump I replaced was a 69 Buick Skylark around 1980, several bolts snapped flush with the block, luckily I had a good back yard mechanic helping. I have a shop manual.
Ed B.
Any evidence of any problem, bearing wear, coolant out the weep hole? If not, I’d probably leave it be. How many miles are you putting on it? If a lot, then maybe replace it.
How’s the fan clutch?
Unless you notice the problems that @texases mentioned I’d wait. It’s on the front of the engine and easy to get to. The main advantage I see is that you will only have to drain the coolant once if you replace the water pump now.
On a car that age if you’re doing all that work I would replace the fan clutch as well to ensure proper cooling.
If you do decide to do that and you’re that far in, may as well replace the water pump. You won’t break any bolts. They are 3/8" sturdy bolts and go into cast iron, not 1/4" going into aluminum and corroding like they did on the Buick.
Agreed, water pump is much easier to get to with everything else removed.
I’m changing my vote-it’ll be so easy to do it, the cooling system’s drained already, about zero chance of breaking something, go ahead and do it, along with a new fan clutch.
I did a little checking and the Buick 350 did have an aluminum timing chain cover, I’m assuming this is what the water pump bolted to? Always good to learn something new, much appreciated.
I’ll keep the water pump and fan clutch in mind. No issues with either at the moment, but the car has 84k miles. I’ll be taking my time with the repair.
Thanks,
Ed
I think I’d change it but also had a bolt break. Had to weld a nut on to what remained to get it off. After that I always coated the bolts with gasket sealer and never had a problem after that. I’d try very carefully trying to see if they loosen up.
If your 93 Caprice has its original water pump, common sense says to replace it as part of the radiator job. Replace the thermostat too, if it hasn’t been replaced in the past 5 years. Might want to replace all the rubber hoses too, esp if any are looking like they’ve seen better days. But definitely less work if you stick w/just the radiator, leave well-enough alone on the others. I can see it from that side too.
As far as stuck/broken fasteners, that risk can be greatly minimized by soaking each fastener with thread penetrant, apply daily for the entire week prior. If a fastener seems to have rust build up where thread meets block, try to scrape the rust bond away at that point the best you can with a steel dentist pick, as part of the penetrant spray work. Clean the fastener heads of anything that might slip before applying the wrench/socket. Start with a gentle force, not full arm strength. If fastener still balks in the reverse direction, try applying a tightening force first. Sometimes some forward/reverse force events over the course of a couple of days are required on really stubborn bolts. Tapping on the bolt now and again can be helpful too, not heavy duty hammering, medium force tapping, like with handle of crescent wrench. .
As for which penetrant to use, I usually use a combo of PB Blaster and my own home-brew. PB Blaster is faster, but my home-brew is better at really stuck fasteners. I put a little of both on. I’ve used Liquid Wrench before too, works nearly as well, but takes longer than PB Blaster.
My home-brew
1/3 acetone
1/3 Mercon 4 automatic transmission fluid
1/3 WD 40
@Bing’s idea to coat threads with something water-resistant before reinstalling can be very helpful the next time. I use moly-lube for that myself.
If you are inclined to try heat to unstick a fastener, not something I usually do, but if you do, suggest to do that before applying thread penetrant. The fumes from heating that stuff are not at all healthy to breath.
fyi, I replaced the water pump on my similar era Corolla about a year ago. Fasteners came off slick as a whistle, no problem at all. I did apply a little of my home-brew penetrant the day before is all. Most of the the bolts screw into the iron block on that design. Moly-lubed the threads before re-installing.
This is a Chevrolet so the proper fluid is Dexron. 
I wouldn’t worry about lubing the bolts, 30 years from now I doubt I’ll be replacing anything.
lol … My Ford truck, only auto-trans vehicle I’ve owned, uses Type F. So you might wonder why I have Mercon 4 on hand? I rented a big E350 Ford panel truck to move household goods from Denver to California one time, and asked the rental company to supply a couple of bottles of transmission fluid just in case it overheated going over the various mountain passes. The truck required Mercon 5, but all they had was 4, so they phoned up a supposed "expert’ who said Mercon 4 can be used in an emergency. The rental truck company had no use for Mercon 4 so they said I could keep it, which I’ve been using for light-oil purposes, & my homebrew thread penetrant.