: Major coolant leak



Eldyfig
03-08-09, 08:37 PM
I need some help friends. It has been quite some time since I have participated regularly here on the forums. I still have my eldorado and she is still my daily driver. Round trip to work is 72 miles. She has 182K on her now. She isn't as pretty as she used to be, but mechanically she has been a champ. Until now...

I had just parked the car at home and noticed some smoking from under the hood. Found that she is leaking coolant. It is coming down somewhere further in than the water pump and leaking down on the exhaust flange. All around the pump is dry. All hoses look okay. But this leak is coming down good while the engine is running. I turned the engine off and it seemed to dissipate. Off for about 10 minutes. Not leaking. Started it back up and it took a couple minutes to start leaking again. Again, it started flowing good. Right now it is too hot to start sticking my hand in there to feel around. Hell, I don't even want to put my face around it. It hasn't overheated. The coolant low level reading came up on the dash and I went ahead and shut it down.

I am thinking it is leaking from the head, maybe? Any ideas? I just bought a brand new tractor (last week) thinking the caddy would last a bit longer. Now. I am not sure. I do not want to put any major money into her anymore and my time for working on her is limited. If it was the water pump, that would have been fine. Me and the girl have been together since 2002. I think this might be the end of the road.

Any help is greatly appreciated. I haven't pulled out the manual yet. Just happened an hour ago.


Maybe I should also mention that starting two weeks ago, the engine idle in park (warm engine) would surge to about 1100 rpm and stick there. It wouldn't do this consistently, just 3 or 4 times in the last two weeks.

Tony

PAULSTSMAN1
03-08-09, 09:21 PM
If the leak is coming from the right side of the car near the firewall, you have quite an expensive job coming. I recently had my 98 STS coolant changed and the Service Department found a slow leak in a Heater Coupling. The Coupling itself costs peanuts, but it always breaks off in the engine block, requiring a "tap out" and hours of expensive labor. I was informed that in the area it's located in it must be worked on by a qualified tech as it can't even be seen. Also several systems must be temporarily removed to access the area. I was told that the design of this coupling is only difficult to repair in General Motors cars, because of it's placement.

I recommend that you don't drive the car, if it overheats with old coolant, your head gasket may go, and that means Mucho Denaro! I know this is the Tech Thread, but in a situation this serious, I thought I might give you what I encountered a week ago!

Let us know how you fared and actually what the Service person found, Good Luck!

Ranger
03-08-09, 09:42 PM
You don't explain very clearly where this leak is, but there are 2 coolant pipes that run to the heater core along the rear head. For some reason they tend to rust out and leak. Not much room between the rear head and the firewall so they are a PITA to change.

Eldyfig
03-08-09, 10:18 PM
Hey Ranger. It's been a while since I have been around. Hope all has been well with you.

I mentioned that it is further in than the water pump. What I meant by that was if you are on the driver's side looking at the pump, the leak looks to be coming from at least 6" further in than the pump. I also mentioned that it is leaking down on the exhaust flange. I meant where the exhaust pipe meets the exhaust header. All of this is not near the heater core. I don't think the leak is from the two pipes that you mentioned. The leak is coming from somewhere on the other side of the engine (radiator side).

The water pump doesn't extend further in than those small bolts on the front of the pump, does it?

Ranger
03-08-09, 11:22 PM
Radiator side? Hmm, only thing I can think of there is the radiator or a radiator hose. Water pump is on the rear of the engine (drivers side).

pimpdaddycaddy91
03-08-09, 11:34 PM
Sounds like it could be one of the crossover gaskets. All four gaskets are like $20. I had my crossover off with the engine out (trans still attached) and wasn't too bad with engine out of the car but I'm not sure how difficult it would be with the engine in the car, but definetely doable.

Eldyfig
03-09-09, 05:46 AM
Radiator side? Hmm, only thing I can think of there is the radiator or a radiator hose. Water pump is on the rear of the engine (drivers side).

Yes and the water pump at the rear of the engine is closer to the radiator side than the firewall side where you had mentioned the two pipes that run along the "rear" head. The radiator and hoses are absolutely fine. I already mentioned this.

Let me try to explain this again in a different way. I originally thought the leak was from the water pump because of the general location. Upon looking at the pump, it seems to be dry all the way around. I can see the leak coming from somewhere just beyond the pump, closer to the engine block. I can't see exactly though. I understand head gaskets going out and leaking coolant internally. Might I have an external leak?

Pimpdaddy, thank you for that recommendation. I will get the manual out and take it to work with me. I'll look up those crossover gaskets and see if that might be it. I think you have the general idea of where I say the leak is.

JimD
03-09-09, 10:48 AM
....

Let me try to explain this again in a different way. I originally thought the leak was from the water pump because of the general location. Upon looking at the pump, it seems to be dry all the way around. I can see the leak coming from somewhere just beyond the pump, closer to the engine block. I can't see exactly though. I understand head gaskets going out and leaking coolant internally. Might I have an external leak?

Do not overlook the fact that there are several possible leak sources that can be attributed to the "water pump".

One is the the pump cover seal (O ring) and a leak would be visable or feelable by looking / feeling in the area of the pump cover / thermostat housing area.

Another is the pump cartridge drive shaft seal (O ring) which can leak and not be seen except by pulling the bottom trim panel and getting under the pump pulley with a strong light source and a mirror (engine at idle).

Both of these sources will put coolant drops on the left bank exhaust system plumbing.

Ranger
03-09-09, 01:48 PM
Head gaskets rarely leak externally so I would not be too worried about that. Sounds like you may be talking about the rear of the engine more than the radiator (left) side. I'd follow Jim's suggestion. With an inspection mirror and a flashlight you should be able to get a look at the shaft seal. I've done it from above. A little tricky but doable as I recall.

tateos
03-09-09, 01:55 PM
Sounds like coolant crossover gaskets to me - tough job in the car

Eldyfig
03-09-09, 11:11 PM
Thank you, everyone, for the replies so far. I was looking at the manual today and got a good look at a picture of the water pump housing. I am starting to think it may be the housing leaking on the block side. I am off the next two days. I will start on it tomorrow. You know, the water pump has not been done since I have owned this car at 92K. It has given a good life.

I'll let you all know what I find.

Eldyfig
03-11-09, 04:19 PM
Never did locate where did the leak is coming from. Figured I would just go ahead and do all the housing gaskets and the pump. Went ahead and bought a new pump with o-ring, thermostat w/gasket, and upper and lower housing gaskets. I just took a break after I got the pump itself out. Looking at that housing, it looks to be a pain to get out.

Let me ask, when crossover is mentioned, are you guys talking about the water pump housing?

Looking forward to replies. I am heading back out to the car. I will check back in a while. If anyone uses a o l instant mess, you can reach me on cell with the same username as I have here.

Eldyfig
03-11-09, 04:57 PM
Never did locate where did the leak is coming from. Figured I would just go ahead and do all the housing gaskets and the pump. Went ahead and bought a new pump with o-ring, thermostat w/gasket, and upper and lower housing gaskets. I just took a break after I got the pump itself out. Looking at that housing, it looks to be a pain to get out.

Let me ask, when crossover is mentioned, are you guys talking about the water pump housing?

Looking forward to replies. I am heading back out to the car. I will check back in a while. If anyone uses a o l instant mess, you can reach me on cell with the same username as I have here.

Another question: the water pump cover gasket is different from the original, parts store website says improved design. The old gasket has what looks like a pull tab that went into a recessed area of the cover like the rest of the gasket. The new gasket does not.

I noticed on caddyinfo that JimD mentioned that he replaced the cover when he did the pump. I am wanting to find out if this is necessary. Has anyone used the old cover with the new style gasket. I should mention that my car is a 94. So, it definitely has the old style cover. I don't know when the new style came out.

Here is a link to Jim's picture of the new and old covers and gaskets. Jim, I hope you don't mind me posting this link. If so, just let me know and I will remove it.

http://drupal.caddyinfo.com/files/images/DSC02149.preview.JPG

JimD
03-11-09, 06:42 PM
....I noticed on caddyinfo that JimD mentioned that he replaced the cover when he did the pump. I am wanting to find out if this is necessary. Has anyone used the old cover with the new style gasket. I should mention that my car is a 94. So, it definitely has the old style cover. I don't know when the new style came out.

When I ordered my parts from Brasington, they asked if the pump cover had been replaced on my '98 model engine. The parts guy said the cover and gasket had been redesigned several times and the OEM ('98) parts were no longer available. The cover and the gasket have to be the same iteration when using GM parts.


Here is a link to Jim's picture of the new and old covers and gaskets. Jim, I hope you don't mind me posting this link. If so, just let me know and I will remove it.

I have no problem with that.

The source of your leak could easily be the shaft seal (O ring) on your pump cartridge.

Eldyfig
03-11-09, 06:57 PM
Thanks Jim. The parts store couldn't tell me for sure. I called the dealer parts dept. and they said the same as you just mentioned. Turns out the new cover is about $50. They said the new cover requires a new style gasket for the thermostat also. After looking at the condition of the o-ring for the pump and all the crud that needed to be cleaned out, I am hoping that is the source of the leak. I am going with that for now. Get a new cover and put it all back together. That pump housing looks too much of a pita unless absolutely necessary.

Ranger
03-11-09, 07:57 PM
Yes, pump housing and crossover are one in the same and Yes, it is a royal PITA job.

Eldyfig
03-20-09, 09:47 PM
Dropping back in to let everyone know how it went. I didn't identify the exact place the leak was coming from. I was hoping it was the pump o-ring, but was figuring to be the crossover. I replaced the pump, o-ring and front gasket. I found the old style gasket at a local store. Last one they had. Took a look at the crossover and told myself there was no way I wanted to mess with it. Here's hoping for the best...

Started adding coolant and supplement. It was almost full when coolant started to come out without the engine running yet. And this wasn't just a drip, drip, It was a steady, skinny stream. I went ahead and started the car to see what would happen. I jacked the car to this side and that and finally found it coming from the crossover. Well, get this...after a few minutes, the leak clammed up, never to be seen again. I have driven it plenty in the last week and still no leak.

I have been looking into getting a truck. I might end up parting this thing out if it proves to be worth it.

Ranger
03-20-09, 10:05 PM
Well, get this...after a few minutes, the leak clammed up, never to be seen again.
The sealant tabs did their thing.

gust_1980
03-22-09, 02:07 AM
could it have been a bad freeze plug? in my 94 sls i had one go bad and was leaking coolant like crazy and dripping on to the exhaust manifold and stunk like crazy! cheap part, expensive labor!!!

Ranger
03-22-09, 12:59 PM
I don't think the Northstars have freeze plugs.

StevinDM
04-01-09, 11:21 PM
I just got done fixing a coolant leak on my 1998 Cadillac Deville D'Elegance. The biggest challenge of all was just pin-pointing the leak. My advice is to follow the upper radiator hose to the thermostat / water pump cover. If your leak is directly below this then you have found the weirdest water pump I have ever seen. :cookoo: The water pump is driven off of the cam shaft closest to the radiator and transmission and about as far away from the serpentine belt as you can get. To make matters even more confusing is that the weep hole that is between the impeller and the belt pulley is stuffed down between what they call the cross over pipe or pump housing. The pulley is facing the block! Good luck actually seeing the weep hole. If the coolant is actually coming from this general area, you will have to remove four pieces to be able to use an inspection mirror and flashlight to find the leak. Remove 1. Both halves of the filter box and it's hose. 2. The water pump belt cover. 3. The plastic cover over the spark plug wires. 4. The narrow plastic shield under the radiator. You can almost see the water pump pulley from underneath the car when you remove that piece of plastic.
I am 80% sure that the original coolant leak was from the weep hole of the water pump. I am 100% sure that the second leak I saw after I had everything back together was from the small hose attached to the water pump cover. This is the easiest and cheapest fix so look there first. Follow the upper radiator hose to the water pump cover. Tucked in behind some wiring looms and a sheet metal bracket is a smaller hose on a hose barb that is part of the water pump cover. You can bend the sheet metal bracket to get at the hose clamp. You maybe able to remove this hose without breaking the seal on the water pump cover. I found this hose barb covered with slime and corrosion as if it had been leaking. I cleaned both the hose barb and inside the hose while changing the water pump. The hose clamp is hard to get to and I didn't get it tight enough and it leaked. You just might get lucky and tighten up this hose clamp and stop the leak. If the hose is in fact leaking at the hose barb, it's best to take it apart so you can clean it up for a better seal.
The water pump it's self can be tricky to remove and install. Find a parts store that rents the specialty tool for removing and installing the water pump. There are two o-rings and the pump comes with only one. You can probably get away with only the o-ring that comes with the pump.
The engineers are sure that you can drive this car for fifty miles without coolant. They must have a lot of confidence in their cylinder head and gasket and it's unlikely that there is a head gasket leak. But there are four gaskets where the cross over pipe attaches to the block. One of these four gaskets could be leaking. The manual says you can re-use these gaskets. I don't want to find out! Looks like a weekend project to me. Tightening up a hose clamp is easier. But first you have to be able to find the leak. :thumbsup:

Submariner409
04-01-09, 11:31 PM
Northstar cooling systems are a mysterious bitch to work on and even more mysterious to someone used to a good ol' fan pulley driven water pump.

Destroyer
04-02-09, 12:25 AM
I am thinking it is leaking from the head, maybe? Any ideas? I just bought a brand new tractor (last week) thinking the caddy would last a bit longer. Now. I am not sure.
TonyHahahahaha! Damn, I just spit up a granola bar and a mouthful of rum/ice tea on my screen. "I just bought a tractor............................" LMAO:alchi:

therodman
04-02-09, 10:49 AM
I got a kick out of that myself, reminded me about a fella I used to work with who had a neighbor ( Jed ) that bought a new tractor. Looking out of his front door he could see Jed on his new tractor and up came a brilliant idea, put a for sale add ( New Ford tractor, must sell, $1000 firm ) in the local paper for Jed's tractor!

A couple of days passed and here comes Jed, he knocks on the door, walks on in and starts telling Dan ( fella I worked with ) that some folks keep calling me about my new tractor, they want to buy it for a thousand dollars, heck I just paid $27k for that tractor, these folks must think I'm stupid, trying to buy my new tractor for $1000.

Dan was always talking about messing with ole Jed and the purchase of a new tractor by a member rekindled that story.

Eldyfig
04-21-09, 11:45 PM
Now that you all got a kick out of that...including myself (I was laughing so hard, my kids thought I was crying)...

I bought that caddy when I had a little lot in a neighborhood. I have since moved and have a bit of land to upkeep and work. Tractor was a must. And now I have bought a truck which is needed much more than a car. No more pimpin for me.

The leak has surfaced again and I am not wanting to put as much work into it that is needed. So the eldorado is now for sale as a whole or parts. Make an offer if you want. I posted in the classified section if anyone is interested.

rainboweed
04-22-09, 08:55 PM
hate to say it. Maybe the block took a hit in the area where 5 & 7 cilinders are. The ext. ridge at bottom of the cylinder . Had one crack on me and didn.t even reach the 230 on my temp gauge, (97 sts) 150,000

Eldyfig
04-22-09, 11:06 PM
Leak has been identified as coming from the water pump housing gasket.

KCMO94Eldo
04-26-09, 04:51 PM
Yes the water pump housing gaskets (crossover) , 4 gaskets triangular shape . Also if you decide to upgrade to the new design water pump cover , youll need to get the new bolts , or use washers on the old ones . The new design cover was thinner , not allowing the old bolts enough material to thread into housing . The new style gasket doesnt fit into old style cover , and i couldnt find the old gasket , so i just bought the new cover , gasket , thermostat kit . If you dont fix it and part it out I need a right front hand splash shield that covers up the alt , a/c comp , and connect to the bumper , PM me if interested .

Crewser
04-26-09, 06:13 PM
Interesting thread - I own a 96 Seville STS with 120,000 km that just last night puked out about a cup or two of antifreeze on the garage floor after I shut the engine down. I've not noticed antifreeze on the garage floor before now but I have had to add coolant on occassion and have noticed a coolant smell as well. The puddle was right between the front tires - perhaps slightly more to the passenger side. The car has never run hot - could it be just a faulty rad cap on the resevoir allowing coolant to escape after the engine is shut down ? Any advise is appreciated.

Ranger
04-26-09, 10:26 PM
Have the coolant tested for the presence of exhaust gases or get a kit and test it yourself. If it is positive, the head gaskets are gone. If it is negative, there are several things it could be. Rule out the gaskets first.

Crewser
04-27-09, 01:29 AM
Blown head gaskets would cause the car to run hot would it not? It would also steam like hell out of the exhaust ... this is an external leak onto the garage floor - can't imagine that is a blown head gasket? ... Just drove the car again tonight ...out for a couple of hours driving .... watched for a coolant leak under the car when I shut it off and there is not a drop. I will look for a kit to check the coolant for presence of exhaust gas -- thanks for the help.

Submariner409
04-27-09, 01:32 PM
If the coolant surge tank is more than half full, COLD, then it is overfilled and the coolant, expanding during warmup and steady running, has nowhere to expand to, so it blows off through the cap pressure relief.

When you shut down an engine the coolant quickly heats up past the normal running temp (but only for a minute or so) because that engine has a LOT of heat retained in the block and guts. It passes the heat off to the coolant, and, if there's enough heat transfer, the fans will come on for a short while. (If the surge tank is filled too close to the top, it will burp out a cup or so of coolant) That's why the fan circuits are hot at all times and the stickers and owner's manual caution that one or both fans may start at any time, even with the engine off. As long as the coolant is above 188 degrees, the thermostat is partially open and there's convection coolant flow, even with no pump running.

Crewser
04-27-09, 09:03 PM
Thanks Submariner - what you say makes complete sense ... I've been in the habit of filling the resevoir to within an inch or two below the top ... more than half-full cold. ... I suppose having it too full could also put pressure on the weakest point in the cooling system .. wheather it be a hose clamp or seal at the water pump ... in a perfect world that weakest point should be the relief valve on the rad cap .... Thanks again ... I think it was you who gave me directions on my trannie problems as well. $3000 and it is good as new !

Eldyfig
04-28-09, 12:43 AM
Just fill the reservoir about an inch in the bottom when looking straight down into it. Submariner is correct and explains it very well.

Ranger
04-28-09, 06:56 PM
I've been in the habit of filling the resevoir to within an inch or two below the top
Two inches is about the halfway point and is the correct level.

Crewser
05-14-09, 03:46 AM
I finally had some time to find the source of my coolant leak. There are two short connector hoses going from the engine to the crossover pipes on the water pump end of the engine. The hose clamps on the lower tube were very loose - I suspect that when I had the transmission rebuilt the mechanic missed tightening this one entirely. Does any one know if this is the low pressure side? - I think I dodged a bullet here by not running the engine dry of coolant unknowingly! Not a easy place to get tools on either.

Ranger
05-14-09, 11:24 AM
There is no such thing as a low or high pressure side of the cooling system. You may be confusing that with the A/C system.

Crewser
05-14-09, 01:50 PM
Yes I guess that makes sense that the cooling system would be all under the same pressure once it gets up to temp. I don't understand how this hose didn't just blow off the engine side bib as loose as the hose clamp was - it literally just spun around on the hose ?

Ranger
05-14-09, 06:20 PM
It's hard to say not knowing exactly which hose. If it was short, there may not have been enough room for it to come off.

gust_1980
05-15-09, 03:29 PM
not that this is of any help at this point, but last month i had a major coolant leak as well and had similar symptoms. come to find out that i had a small pinhole at the bottom of my coolant reserve that would only leak under pressure. very easy and cheap fix and now im running fine!