85 Eldorado 4.1 Water Pump Problems

Chevy One · #1 (**permalink**) 01-15-09, 02:04 AM

Hello all need help! Installed new water pump having problems with the tube, which crosses from thermostat housing to manifold. Tube had rust in o-ring areas. Wire brushed tube then placed a thin bead of silicone on tube areas where o-rings are placed. Installed o-rings then another thin bead of silicone. Installed pump, thermostat housing and cross tube as one assembly. Leak seams to be coming from manifold side. Question’s I have: can I remove thermostat housing and tube without pulling the pump again??? Should I replace the tube with a new one if one is available from the dealer still? Tube dose have some pitting but the silicone should have helped this, maybe I should not use the silicone. Or should I try to re-clean the tube, seal again and re-install thermostat housing and tube again. I am a seasoned mechanic and I have to say this pump assembly is one of the poorest engineering I have ever seen! Silicone is red high temp.

Thanks,
Chevy One

xPosTech · #2 (**permalink**) 01-15-09, 09:59 AM

I would try to locate a new or used tube in good shape. I've never had good results using RTV on bare metal. RTV contains acetic acid (that vinegar smell) which promotes corrosion.

I have filled rust pitted steel tube connections with solder. Remove all rust (I've used high strength vinegar

), clean, flux well and tin well with solder. Then dress it back down to original surface size. This is usually done on a restoration when new parts are unavailable.

Good luck.

Ted

Chevy One · #3 (**permalink**) 01-15-09, 02:23 PM

Ted,
Thanks for the reply the main question I have is; can the cross tube be removed and re-installed without having to pull the whole pump again just being able to pull the thermostat housing and cross tube? It looks like it would be tough because the cross-tube is sandwiched between the thermostat housing and the mainfold! if you have done this before you know what I am facing here.
Thanks Again,

CP

Chevy One · #4 (**permalink**) 01-16-09, 12:08 AM

Guess I'll answer myself here; tried to pull the thermostat housing, if I pry hard enough it would come off and most likely break the water pump and/or thermostat housing too. Will have to loosen and slide the pump back a little. Looks like I am working on a out of date Eldo here for anyone on this site to be able to help and answer here. Or maybe this old Chevy One is a better gear head than you Cadillac folks. I forgot people that can afford Cadillac don’t have do there own maintenance. Sorry to say I'll take my small block Chevy any day over a Caddy, I can out-run any of you and they are easy to work on and parts are plentiful!!!

xPosTech · #5 (**permalink**) 01-16-09, 02:11 AM

I'm glad you stopped before breaking the tube. Most of us Cadillac folks might not know something might break if you put too much pressure on it.

Glad you're a gear head who knows his limitations. Too bad you don't know the limitations of a Chevy small block.

Sorry I can't help you on the tube removal. I've never removed one. But you have removed one, haven't you? Just recently?

Ted

xPosTech · #6 (**permalink**) 01-16-09, 02:22 AM

What the heck. You asked for help, even if you tried to reneg on it.

Do an advanced Google search with "site:cadillacforums.com" (without the quotes) in your search string. Don't forget to insert whatever you're searching for.

IE: Eldo 4.1 "water pump problems" site:cadillacforums.com or
Eldo 4.1 "coolant crossover" site:cadillacforums.com.

Good luck to you.

Ted

Chevy One · #7 (**permalink**) 01-16-09, 10:51 AM

Sorry about the comments just needed to vent. If you know anything about a Chevy small block there are no limitations the small block is the highest production motor to date. You can start from the 265 cc motor and push them to over 500 cc with the right components. I have a 67 Chevy II 2dr HT with a 327, which pushes over 400 HP. It dose not have all the whistle and bells your caddy's have but it gets me from point A to point B in style I might add. Yes the ride is not as smooth as yours but I can change a water pump is under two hours not two days with no leaks to boot!!! My little Nova turns heads everywhere I go. I am well aware that in the eighties all of the big three were pushing junk off the assembly lines and today’s technology is awesome but the simplicity of yester year has it benefits of ease of maintainability which to us that can’t afford to buy new is always a plus.

xPosTech · #8 (**permalink**) 01-16-09, 09:56 PM

I've seen the same arguments for a Model T. All you needed in the tool box were chewing gum, pliers and scraps of leather.

BTDT

Ted

carnut · #9 (**permalink**) 01-18-09, 04:02 PM

The pipe is installed first into the intake then the water pump. Remove the coolant temp switch and then pry the tube forward into the ther. housing. Did this job last year and got a new tube and o rings. Hard to find. Had to drive 60 miles to a Cad dealer to get it. With the coolant temp switch removed, you can see just how far to insert the pipe. Leave enough room to get a wide blade screwdriver in there behind it to pry it forward. Also good idea to clean the area in the manifold and housing with crocus cloth and use wheel bearing grease on the pipe o rings. As you know, there is a forked piece of metal that goes down over the pipe to center it between the manifold and housing. Sorry, but the water pump must virtually come back off.

Chevy One · #10 (**permalink**) 01-19-09, 01:58 AM

Ya I found out that needed to remove the pump again, got new tube and o-rings. This time it took me one long day. No leak this time, was letting the car idle making sure everything running good when the heat control valve broke on the fire wall side dumping all the new antifreeze. Back to the parts store again.