View Full Version : 84 4.1 Brougham water pump bearing bad

05-03-13, 09:09 PM
My Brougham recently started to make a high pitch squealing noise on and off. I was certain that I just needed to replace the Alternator belt, but after replacing the belt, she still squawked. So then I thought to myself, "It must be the Alternator bearing then." since I noticed the squeal got louder when there was any draw from the Alternator. So I replaced it. Caddy is still screamin'.. noticed that the Water Pump was feeling mighty hot though.

I'm pretty certain this is the issue.. while the pump is inexpensive, I could use any help anyone has to offer on how to get to the thing. It looks like I might have to remove a pulley to get to it. Anyone have any experience with this, or maybe a guide?
The engine, unfortunately is the infamous HT4100. I would like to put a new motor in all together, but that is just not feasible for me at the moment :-/


05-03-13, 09:17 PM
Take the belts off and spin each component by hand. That may help you figure out which one it is.

05-03-13, 09:39 PM
I already replaced the alternator and all the belts under the hood. I'm pretty certain the water pump bearing is bad. I'm just looking to see if anyone has experience with removing the water pump from the 4.1 because it looks like it's going to be tricky.

Robin Banx
05-03-13, 10:35 PM
Been there.......done that. My 83 4.1 Bro tossed its water pump at 51,000 miles from brand new last year. The pump was throwing coolant from behind the pulley so it was easy to identify the problem. If it is your pump, there are several things to watch for when replacing the pump. The re and re is somewhat difficult because as I recall there is a mounting bolt behind the power steering pump pulley. I might be wrong but then my memory is shot. I would have an experienced shop make the change if I were to do it again. The reman pump housings are usually shitty, pitted and degraded to the point of being unusable. Moving on, my mechanic rejected 2 reman pumps I supplied so I bought a new one which he installed. The water manifold (that's right) on the left side cylinder head had to be draw-filed to ensure flat sealing surfaces and the assembly was a nightmare. It leaked for 9 months and finally I had to agree to live with it until the engine change. So......three things to consider. One, have an experienced shop do the change. Two,, make sure that the replacement pump is a factory fresh unit. Three, be prepared for some serious leaking problems. Bear in mind that I have refused to use the GM shit pills in my cooling system to let them of the hook for coolant leaks. You will have headaches related to this repair but if you can arm yourself with as much info as you can, hopefully the pump replacement will be successful and you will get lots more happy miles out of your 84 Cad. I did, and at the moment I am a happy Cad motorist.


05-04-13, 08:29 AM
Yeah I replaced the water pump on 2 HT-4100's last year (one on mine, then helped a buddy with his).
You need to get a special tool to remove the power steering pump pulley.
I might be missing a couple small things and the order might not be 100% right (you'll have to look at what makes sense in the engine bay)
You have to remove the fan shroud
drain the coolant
remove the fan/clutch assembly
remove the water pump pulley
remove the alternator
remove the harmonic balancer
un-bolt the A/C compressor
remove the bracket that connects the A/C and the alternator and air pump
loosen the vacuum pump (or take it's pulley off with the special tool)
remove the power steering pump pulley
disconnect Rad hoses
Remove the water pump

you'll then need to transfer over the timing gauge, pulley studs, and thermostat housing from the old pump to the new one.

The assembly is the reverse of what you did to take it apart (getting the alternator/AC/air pump bracket in can be a royal PITA).

Then you MUST tighten the Air pump to re-tighten the water pump belt. The adjuster on the Air pump is so hard to get at that I recommend you take it to a shop with a lift for that last step (only takes 5 mins with a lift). After I did the pump on my car, the belt came loose and I took it to a dealership to tighten it. It cost me $30 and they give it a free hand car wash while I drank their complementary coffee/pop and ate cookies.

The whole job is a huge job. It took me and my buddy 4 hours to do it in his driveway even with me knowing exactly what to do. (don't jack the car up since it can all be done with it on the ground and your back will thank you for leaving it down)

05-04-13, 10:15 AM
Seriously guys, huge thanks. This is a lot of important information, and it wont go to waste. Now I'm just bracing myself for the road ahead. I hope everything goes smoothly and I don't end up with any leaks afterward.
These GM tabs for the cooling system.. is there still anything like that you can add to the coolant? I tried squirting some oil down in there in the hopes of lubricating the bearing until I am able to get cracking on this, but no such luck.

05-04-13, 10:32 AM
yeah, you can get the tabs from the dealership. a 6 pack cost me ~$4 for the delco tabs. You need to add 1 tab for each 2 quarts of new rad fluid I believe.


I guess I should clarify that it took 4 hours just to do the one on his car, not both of them.
Mine took a couple weeks because I didn't know about the special tool and broke my power steering pump pulley trying to get it off, then had to wait for new parts to come in.

The Ape Man
05-04-13, 07:35 PM
R U 100% sure it isn't just the A.I.R. pump belt being loose? That belt drives the water pump which steps up speed to the alternator. Plenty of people hear that screech and just keep tightening the alternator but it doesn't work. With engine off try spinning alternator. If you can spin it the belts are too loose.