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Unidentified Coolant Leak


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I went out tonight to take my car for a test drive after putting in the new plugs and wires and all. I started it and was letting it warm up to operating temp to see how it was idling. It was purring like a kitten. =) I had the hood open so I could keep and eye/ear on everything, and as the temp went up I started to hear a slight squeak coming from the driver side of the engine, near the water pump belt/pulley assembly. That squeak quickly turned into a squealing noise, and I looked all over but saw nothing out of order. I smelled an odd smell...couldn't put my finger on it at first, but shut the engine off for good measure. I looked around some more and found a very small puddle of coolant on what I believe is the water pump cover? I'm not sure, which is why I am putting a pic here.

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Is this the water pump cover? And what, other than a pinhole under this little puddle (which I didn't see when I cleaned it up) would cause a leak here? I looked everywhere and nothing else had coolant on it. I also checked the coolant tank and it didn't appear to be low, but I wouldn't expect it to with only losing that small amount of coolant. I am guessing the squealing noise may have been the water pump...but I can't be sure.

For those who don't already know, my car is a 1994 Caddy Eldorado, 4.6 Northstar. I thought I had it all figured out, and of course something else just HAS to go wrong.....lol. <_<

As always, any help is appreciated.

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The good thing is that it is external. Dry that spot out. Start the engine and increase RPM to some 4000. Watch carefully the suspected area and you will most likely see the leak under increased pressure. Waterpumps are easy to replace on Northstars.

The saddest thing in life is wasted talent

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That is the water pump cover. With the engine off, take a look at your water pump belt, check to see if its cracked or glazed from slipping. The belt tensioner can bind and not put proper pressure on the belt.

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

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The good thing is that it is external. Dry that spot out. Start the engine and increase RPM to some 4000. Watch carefully the suspected area and you will most likely see the leak under increased pressure. Waterpumps are easy to replace on Northstars.

This little puddle formed at an idle in a matter of about 5 minutes, before the temp even got over 150, so it shouldn't be hard to duplicate. In the event that it IS a pinhole leak under where the puddle is, would I still have to replace the water pump? or just the cover? The loud squealing noise also concerns me a bit since I never heard it before today... Also, I failed to mention previously that the odd smell I smelled seemed to be that of burning/very hot coolant.

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Just the cover and a new cover gasket. When you do that replace the thermostat and stat seal also, its in the cover...

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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That is the water pump cover. With the engine off, take a look at your water pump belt, check to see if its cracked or glazed from slipping. The belt tensioner can bind and not put proper pressure on the belt.

I did notice a few small cracks in the belt, but it didn't look glazed. They looked more like old age cracks to me. I will go out in the morning and give her another lookover, start it up, and see if I can tell exactly where the leak is coming from. I would do it now, but trying to run a drop light and an extension cord out a second story window to my driveway 40 feet away is kind of a PITA....and I've already had to do it twice this week. By the sound/look of things, I'm thinking a new cover and belt are in order. If I have to go through all the trouble of replacing the belt, I may as well go ahead and swing for a new water pump too probably (money permitting...I hear they aren't that cheap). I'm tellin ya, if I didn't love this car so much, I would have called it quits by now. My back is killing me. I just keep trying to look to the light at the end of the tunnel, but it seems every time I'm there, it runs in the other direction! Lol. Good thing I'm not afraid of the dark. :P

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That is exactly the type of "nuisance leak" that the GM cooling system sealant pellets or Bar's Leaks Golden Seal product can solve.

If it was my car, I would not even consider replacing the water pump cover or the water pump cartridge before I tried the above products for a period of time.

The noise is a separate issue. Possibly the water pump belt or the belt tensioner.

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

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That is exactly the type of "nuisance leak" that the GM cooling system sealant pellets or Bar's Leaks Golden Seal product can solve.

If it was my car, I would not even consider replacing the water pump cover or the water pump cartridge before I tried the above products for a period of time.

The noise is a separate issue. Possibly the water pump belt or the belt tensioner.

Well, if the belt has cracks in it, then common sense tells me I should replace it. My next question is can I replace the belt without having to remove the water pump/pump cover? If I have to remove the cover to change the belt, then I may as well replace the cover while I'm at it. Has anyone else had to replace this belt before? If so, is it as big a PITA as it looks like it will be?

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Carla, don't replace the pump. There is nothing wrong with it. If the pump fails, it will leak from the shaft seal on the other side. Look closely at the picture. You can see dried coolant above the puddle. Early Northstars had a problem with the cover gasket and it was redesigned. I think the cover was as well. The gasket is only about $10.

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Belt replacement is not difficult. Nor is belt tensioner replacement (if that becomes necessary to solve your noise issue). It is not required to open the cooling system to replace the belt or the tensioner. Don't complicate the task!

Plenty of folks on here routinely change the water pump and serpentine belts every 100,000 miles. Me included. It's not a big deal.

;)

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

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I will give it a good going over tomorrow morning and see if I can pinpoint both the leak and the noise. I'm sure that will help in determining exactly what needs to be fixed and/or replaced. I will post my findings. I'm kinda bummed cuz I was really hoping to be able to bring it to my brother's HEATED garage for a test drive and to be able to do the whole EGR cleanout (with some WOT along the way), but I guess that will have to wait. Better to be safe than sorry, and I don't take chances with coolant leaks, no matter how small. I don't want to break anything else.

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I will give it a good going over tomorrow morning and see if I can pinpoint both the leak and the noise. I'm sure that will help in determining exactly what needs to be fixed and/or replaced. I will post my findings. I'm kinda bummed cuz I was really hoping to be able to bring it to my brother's HEATED garage for a test drive and to be able to do the whole EGR cleanout (with some WOT along the way), but I guess that will have to wait. Better to be safe than sorry, and I don't take chances with coolant leaks, no matter how small. I don't want to break anything else.

Carla,

You might have another leak as well if you were smelling burnt coolant... Watch closely. If the leaks are small (say, a pint after 1000 miles), I would leave them alone till Spring. Bars Leaks powder can help, as JimD said.

The saddest thing in life is wasted talent

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.... If the leaks are small (say, a pint after 1000 miles), I would leave them alone till Spring. Bars Leaks powder can help, as JimD said.

I have been adding coolant to my system due to a "minor leak" for three+ years! My coolant loss is from the water pump cover or the water pump cover O ring. Large doses of Bar's Leaks Golden Seal powder keeps the situation under control.

"Minor leak" being approximately one quart of coolant per 2,000 miles.

I don't sweat the small stuff.

Jim

Drive your car.

Use your cell phone.

CHOOSE ONE !

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It's not the leak that worries me so much as the squealing. I'd hate to be driving down the road and have my belt break, or worse, have a pulley seize up. When I figure out what's making the noise and get it taken care of, I'll feel better about driving it. For now I'd rather not take chances. I like my car a lot better when it runs. I try not to sweat the small stuff, but in my experience small stuff usually turns into big/expensive stuff, and with having so much bad luck in the last 2 weeks with my car can you really blame me? lol. :blink:

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If the car has over 100,000 miles on it and the belts are original, I would suggest replacing the belts - water pump and serpentine belts. The squeal from the tensioner area is probably a bad bearing on the tensioner pulley - about $10.00 from rockauto.com. Over time, the grease dries out of the bearing and it begins to squeal.

Drain some of the coolant and install a tube of the Bars Leaks golden seal (which is the same as the GM product) in the upper radiator hose and then top off the coolant. The minor coolant leak should disappear.

Kevin
'93 Fleetwood Brougham
'05 Deville
'04 Deville
2013 Silverado Z71

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Thanks for all the input. We have had a torrential downpour in my area going on all day today, so I haven't been able to get under the hood. If it happens to let up at all I will definitely pop outside for a few minutes to check things out. Stupid rain....at least it's sorta warm out (48 degrees). :blink:

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Thanks for all the input. We have had a torrential downpour in my area going on all day today, so I haven't been able to get under the hood. If it happens to let up at all I will definitely pop outside for a few minutes to check things out. Stupid rain....at least it's sorta warm out (48 degrees). :blink:

Same here, high winds and heavy rain but its 50 out

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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At least you don't have to shovel rain!! -_-

this is true, lol. But I can deal with being out in the snow, I can't deal with being poured on, especially when I'm trying to do something. I don't think my engine would appreciate it much either... I took this apartment because it has a big yard and driveway...next time I'm making sure there's a garage too, lol.

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It finally quit raining (better late than never) so I went outside, armed with nothing but a little LED flashlight to try and pinpoint this leak and squeak. (hey that rhymes, lol)

The coolant was seeping from this little spot...coming up from under where the puddle was last night. There is some gunk in there, but I am afraid to clean it out for fear of making the leak worse. Leak found. No big deal really. It took about 10 minutes for there to be a noticeable amount there at an idle. You can see my belt in the background on the right....it doesn't look happy. I need a new one ASAP.

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The squeak, I am quite sure, is coming from this guy. I'm not 100% on that because sounds do tend to bounce around a little in there, but I am almost positive. Problem now is, where the heck do I get another one of these pulleys? I have checked every website I can find, and no dice. Junkyard part maybe? In the event that I DO find one in a parts store, any ideas on a price?

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Its not likely that your large CAM pulley is bad, check the tensioner, there is a small pulley on it, that has bearings that can go bad, here is a better photo of the area. In this photo, I have a 1/4 inch breaker bar in the tensioner at the pulley. Check that small pulley, and check the belt

WaterPumpandRadiator008.jpg

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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At least you don't have to shovel rain!! -_-

Can I have an AMEN brother.

55 degrees with wind and rain yesterday, to 30 degrees with wind and 3 inches of snow on the ground today. Only in New York. Time to get out the shovel...

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Its not likely that your large CAM pulley is bad, check the tensioner, there is a small pulley on it, that has bearings that can go bad, here is a better photo of the area. In this photo, I have a 1/4 inch breaker bar in the tensioner at the pulley. Check that small pulley, and check the belt

WaterPumpandRadiator008.jpg

What is it you had to remove from that black bracket on the upper right to get to it? I'm hoping I don't have to move much out of the way...it's getting cold out here again.

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Yes, to get to that point you need to remove two nuts and one bolt to get the shroud off, plus if I recall there is a wire wrap attaching a wire to it. The bolts/nuts were 10 mm in 96, not sure about 94

Be careful not to drop the bolt, its located in a tight spot

Pre-1995 - DTC codes OBD1  >>

1996 and newer - DTC codes OBD2 >> https://www.obd-codes.com/trouble_codes/gm/obd_codes.htm

How to check for codes Caddyinfo How To Technical Archive >> http://www.caddyinfo.com/wordpress/cadillac-how-to-faq/

Cadillac History & Specifications Year by Year  http://www.motorera.com/cadillac/index.htm

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