coolant dripping from mid-section of car!

[formulabird428]

I just got done replacing the driver valve cover gasket (5.0L) in my 89' GM w/239k miles. That also required replacing the throttle body gasket, since I took it off to make way for the VC removal. I start the car up, no leaks. I then go to the back of the car, only to find a pool of antifreeze. My first thought was that I didn't properly clean the throttle body gasket off, so the coolant was leaking through the throttle body, through the engine, through the exhaust (which has pinholes here and there), and then drip onto the ground.

But, the more I thought about it, that's almost impossible since the coolant was still liquid. I'd imagine that would also rule out the head gasket too. I looked into the radiator and the radiator was only about 1/3 full. Definitely have a leak, and a big one. This just started happening today and the car didn't run for more than 2 minutes, so again, I don't think the throttle body could delivery that type of volume...could it?

So, what I am looking at? Heater core leak? Heater hose? Keep in mind, the driveway (car) is sloped a little, so it's possible that the coolant was running all the way down the car from the firewall. Also, I had always had a slight coolant leak, but couldn't ever figure out where. Maybe it was a small leak and now it burst open?

I'm going to go back out tomorrow, but it's very cold and it's been snowing all day. Just trying to get some info prior to freezing outside.

Thanks!

[86VickyLX]

I just got done replacing the driver valve cover gasket (5.0L) in my 89' GM w/239k miles. That also required replacing the throttle body gasket, since I took it off to make way for the VC removal. I start the car up, no leaks. I then go to the back of the car, only to find a pool of antifreeze. My first thought was that I didn't properly clean the throttle body gasket off, so the coolant was leaking through the throttle body, through the engine, through the exhaust (which has pinholes here and there), and then drip onto the ground.

But, the more I thought about it, that's almost impossible since the coolant was still liquid. I'd imagine that would also rule out the head gasket too. I looked into the radiator and the radiator was only about 1/3 full. Definitely have a leak, and a big one. This just started happening today and the car didn't run for more than 2 minutes, so again, I don't think the throttle body could delivery that type of volume...could it?

So, what I am looking at? Heater core leak? Heater hose? Keep in mind, the driveway (car) is sloped a little, so it's possible that the coolant was running all the way down the car from the firewall. Also, I had always had a slight coolant leak, but couldn't ever figure out where. Maybe it was a small leak and now it burst open?

I'm going to go back out tomorrow, but it's very cold and it's been snowing all day. Just trying to get some info prior to freezing outside.

Thanks!

Heater hose with pinhole leak possibly. I'd be leaning towards either that or, a leaking intake gasket, or a leaking EGR cooler line, since that's on the back of the lower intake and could appear to be leaking as you are describing. Your best bet would be to fill it, and hook up a coolant pressure tester. You shouldn't have to pressurize it more than 12psi to find your leak. You don't want to stress old cooling system parts anyway.

[MattDoscher]

+1 w/ what 86vickylx said. When I replaced both heater hoses on my '91 Grand Marquis I used the metal heater tube (back when the engine was rebuilt the metal tube assembly was bypassed for whatever reason). On the rear of the metal tube assembly there is a smaller nipple that forks off and up towards the throttle body. It ended up that my EGR coolant line had been cut in half and not knowing this beforehand I started up the car after replacing both heater hoses I had a coolant leak in the middle part of the car. I had previously not known about this hose or that it was cut in half. Took me forever to find it. As you know it's hard to get at. But that small 1/4" hose could be your problem (there's 2 actually).

[formulabird428]

After going out this morning, the verdict is that it is leaking from the throttle body. Apparently I didn't scrape the old gasket off enough, and now coolant is in the oil. That was raw coolant spewing out of the exhaust (through pin holes in the muffler).

Now what?

Could I "flush" the coolant out of the engine, without tearing it apart?

[jaywish]

Change the oil & filter. If there is some small amount of moisture remaining it will evaporate out the pcv as the engine oil gets hot and runs for awhile. That is about all you can do.

Jay

[marquisman]

good thing you caught this early, so you will prolly get away with oil and filter change. thats why its important to be observant and check your oil. bearings dont like coolant lol

[formulabird428]

OK, so I drained the coolant/oil and it was still oily, so maybe I can get by with changing the oil/filter. In fact, I'll probably run the car for a few minutes, and then do a 2nd change.

Now, as far as fixing that leaking throttle body gasket -- is it possible that the leak is coming from the EGR? I just want to rule anything out, so that this never happens again. Is there a rubber gasket I can use instead of the thin FEL-PRO paper gasket? RTV silicone?

[marquisman]

using hi-temp RTV will help. make sure the surfaces are clean as possible.

[86VickyLX]

OK, so I drained the coolant/oil and it was still oily, so maybe I can get by with changing the oil/filter. In fact, I'll probably run the car for a few minutes, and then do a 2nd change.

Now, as far as fixing that leaking throttle body gasket -- is it possible that the leak is coming from the EGR? I just want to rule anything out, so that this never happens again. Is there a rubber gasket I can use instead of the thin FEL-PRO paper gasket? RTV silicone?

It's the EGR spacer. Those are two lines coming from the back of it that put coolant on there. Bypass them.

[formulabird428]

It's the EGR spacer. Those are two lines coming from the back of it that put coolant on there. Bypass them.

so you think it is leaking from a place other than the throttle body? keep in mind I only took off the throttle body. Also can I just disconnect those 2 lines and e g r system? if so what is the best way to do that?

[mercurygm88]

The egr spacer is the block between the throttle body and upper intake there are two coolant lines on the back that recirculate coolant throught the egr spacer. To bypass them you could simply get a piece of plastic tubing the right size and hook it between the two lines so they no longer go to the egr spacer. But there may be a better way to bypass them I still have mine hooked up and so far no leaks.

[86VickyLX]

What MercuryGM88 said. Also, leave your the actual EGR system alone.

[BerniniCaCO3]

It could be a good time to just pull the intake, and redo the egr coolant lines, along with any vacuum lines that are aged, and the pcv valve/screen/grommet.

It doesn't fix your particular problem, but redoing other coolant hoses is also a good idea, if they're original. I had my lower radiator hose blow on the highway and luckily caught it before the engine was more than slightly overheated. Fixed it, and the very next day the heater core hose went (one of them)! I limped 2 miles home, with a belch of steam every time some coolant pumped out and onto the exhaust manifold, and a corresponding jump in the temperature needle... After that I elected to do 'em all! It's two years later and no issues.
Use good hose clamps btw. Harbor freight ones are worthless, home depot ones work but might need re-tightening, and Norma seems definitely superior in quality.

[formulabird428]

OK, looks like I'll tackle this problem on the weekend. I'll be replacing the gaskets and using some high-temp RTV too. I hope everything works out, because I really love this car. It's been good to me, 239k miles and I hope to keep going!

[MattDoscher]

What are the pro's and con's w/ bypassing the EGR coolant lines? Do they somehow cool the incoming air into the intake?