What is this hose that has Antifreeze leaking out of it?

[BLK BRD 88]

Last week I started our 84 SVO for the first time in a month & drove it to the post office.
When I got back I noticed that antifreeze was leaking under the car behind the right front wheel.
I didn't have time to check it out then, but today I again drove it to the P.O. and again when I got home it was leaking.
I finally found the source, but have no idea what this short hose coming out of the firewall is for.



It is down about half-way on the right side of the firewall.
I started the car & let it idle to full warm this evening, then turned on the heater & defroster....no antifreeze smell, & no fog on the windshield.
I thought that it might be a leaking heater core. All of the heater and radiator hoses are tight & dry.

Any helpful advise will be much appreciated.
Ron

[wraithracing]

That appears to be the drain line from the HVAC box. Unfortunately if there is coolant leaking out of the hose that means the heater core has a leak and that is where the coolant is coming from. Sorry Buddy!

Trey

[TopGear85]

Awesome Ron, looks like the dash has to come out. Hey, I need to take my dash out on the 85...we could do it together and have a dash removal party?

[BLK BRD 88]

That appears to be the drain line from the HVAC box. Unfortunately if there is coolant leaking out of the hose that means the heater core has a leak and that is where the coolant is coming from. Sorry Buddy!
Trey

I certainly would never question what you are saying Trey, but I thought if the core was leaking I would smell it in the car, & that the windshield would fog up when the heater/defroster is on?

Other than that, you have told me exactly what I feared, since I couldn't imagine where else that antifreeze could come from at that point.
Ron

[BLK BRD 88]

Awesome Ron, looks like the dash has to come out. Hey, I need to take my dash out on the 85...we could do it together and have a dash removal party?

Mike, that is an awfully nice offer, but I have never much been into dash removal parties, or anything else that has to do with dash removal.
Ron

[wraithracing]

I certainly would never question what you are saying Trey, but I thought if the core was leaking I would smell it in the car, & that the windshield would fog up when the heater/defroster is on?

Other than that, you have told me exactly what I feared, since I couldn't imagine where else that antifreeze could come from at that point.
Ron

I would agree that its rare that you don't smell the antifreeze in the car. Although I have seen a few leaking cores that you didn't see the fog or haze until the engine was at full operating temp or above. Just sitting in the driveway running, the core would leak out of the drain tube, but no fog or haze inside.

Before you pull the dash to make the swap, you could pull both hoses off the heater core and test it with some pressurized air or even try to pull a vacuum on it if you want to verify. Unfortunately I would bet that the results will still show a leaking core.

Best of luck with the repairs.

Trey

[TopGear85]

You don't know how to have fun. Sorry about your svo.

[BLK BRD 88]

You don't know how to have fun. Sorry about your svo.

Dang, you have a funny idea about what fun is........LOL

We are going to Mixteca tomorrow evening.
Why don't you stop by, since you know that part of town so well these days!
Ron

[BLK BRD 88]

I would agree that its rare that you don't smell the antifreeze in the car. Although I have seen a few leaking cores that you didn't see the fog or haze until the engine was at full operating temp or above. Just sitting in the driveway running, the core would leak out of the drain tube, but no fog or haze inside.

Before you pull the dash to make the swap, you could pull both hoses off the heater core and test it with some pressurized air or even try to pull a vacuum on it if you want to verify. Unfortunately I would bet that the results will still show a leaking core.

Best of luck with the repairs.

Trey

After going back under the car for another look, I can't imagine how antifreeze could get to that hose if it weren't a leaky core.

Thanks for your help Trey....even if it wasn't what I hoped to hear.
Ron

[Sinister]

do you run your car in winter ? or do you need heat ? if not just by pass it, one less thing to worried about again.

[1fst86]

Pressure test ur cooling system, that'll give u the answer ur looking for.

[BLK BRD 88]

do you run your car in winter ? or do you need heat ? if not just by pass it, one less thing to worried about again.

I have been thinking of doing that very thing. On a turbo car can I just get a short length of pipe to put between the inlet & outlet hoses & clamp them together?

Pressure test ur cooling system, that'll give u the answer ur looking for.

You are right, & thanks for that idea. I may buy one of those pressure test kits from Harbor Frieght today.
Ron

[wraithracing]

You are right, & thanks for that idea. I may buy one of those pressure test kits from Harbor Frieght today.
Ron

Hey! Didn't I suggest the same idea in Post #6 above!? Although I suggested just the heater core, so you could verify, it's still the same!

Trey

[BLK BRD 88]

Wow, Trey, I feel really bad that I didn't give you credit for having the idea first. So here goes:

You are right, & thanks for that idea. I may buy one of those pressure test kits from Harbor Frieght today.
LOL
Ron

[wraithracing]

Thanks Ron! I feel much better now!

So is it fixed yet?

Trey

[BLK BRD 88]

Thanks Ron! I feel much better now!

So is it fixed yet?

Trey

FUNNY!!

I am trying to figure out what diameter the hoses are so I can merely shut down flow to the heater core by connecting them to a pipe that will fit tight inside of them.
Ron

[wraithracing]

5/8" should work just fine. If you just need to bypass the core for now, a section of 5/8" heater hose looped between the two heater pipes should do the trick. Although I have to confess I have never done the bypass on an SVO, only on 5.0 V8's. So the pipes going to the heater core, might be a different size, although I don't believe the SVO uses any different heater core than a non SVO Mustang, so it should work.

Good Luck! I guess down there in Phoenix you can get by without a heater, can't do it up here in CO this time of year!

Trey

[82GTforME]

Ron, there was a post on SVOCOP recently that specified a Dayco B87618 as a good bypass hose. http://www.svocop.com/forum/showthre...er+bypass+hose



I didn't have that knowledge when I did mine on my '86 but I did confirm:

"Both of the metal lines connecting to the engine are 5/8" OD. I removed both of the factory hoses and looped a hose to bypass the core."



PS: I still haven't done my core

[Gemini1999]

I think that this is something I need to look into as well... If I had bypassed the heater core, I would have been putting a few more miles on mine than I have been.

[webestang]

I would agree that its rare that you don't smell the antifreeze in the car. Although I have seen a few leaking cores that you didn't see the fog or haze until the engine was at full operating temp or above. Just sitting in the driveway running, the core would leak out of the drain tube, but no fog or haze inside.

That's how mine failed.....no smell or hazing window, just leaked out of that drain hose.

[BLK BRD 88]

Ron, there was a post on SVOCOP recently that specified a Dayco B87618 as a good bypass hose. http://www.svocop.com/forum/showthre...er+bypass+hose

I didn't have that knowledge when I did mine on my '86 but I did confirm:

"Both of the metal lines connecting to the engine are 5/8" OD. I removed both of the factory hoses and looped a hose to bypass the core."

PS: I still haven't done my core

Thanks for that helpful info. I will definitely look into that.
I guess I also need a short length of pipe to connect together the two hoses that originally went to the core.

That's how mine failed.....no smell or hazing window, just leaked out of that drain hose.

Here is the weird thing. We loaded a bottle of mixed antifreeze & a funnel into the SVO this morning & headed out on a 60 mile trip. The car never dripped a drop: cold, hot, idling, or parked. It did have a slight smell of antifreeze & a couple of puffs out of the center vent when we first started out, but we never smelled it again & no pufs after the first five miles.
I am really stumped now.

Is it possible that the previous owner put some kind of stop-leak into the cooling system that is still sealing small leaks?
It seems like I read somewhere, that we should never use that stuff especially in a turbo car??
Ron

[grabbergreen84]

Could be expanding and contracting, hence opening and closing the leak?

[Jerry peachuer]

It could be left over fluid from a previous fix as for the pipe maybe a piece of pvc or copper may work for you kinda no different than a home water heater for the bypass portion of the fix .... tube and pipe do measure differently one measures I.d pipe and the other measures o.d tubing

You could always rotate your radiator cap one turn to keep it locked but in a VENT or PURGE pressure state not ideal but it will eliminate pressure on the possible leak area but this will have a adverse effect for you coolant Flow and your boiling point of your fluid theory

[82GTforME]

Thanks for that helpful info. I will definitely look into that.
I guess I also need a short length of pipe to connect together the two hoses that originally went to the core.



Here is the weird thing. We loaded a bottle of mixed antifreeze & a funnel into the SVO this morning & headed out on a 60 mile trip. The car never dripped a drop: cold, hot, idling, or parked. It did have a slight smell of antifreeze & a couple of puffs out of the center vent when we first started out, but we never smelled it again & no pufs after the first five miles.
I am really stumped now.

Is it possible that the previous owner put some kind of stop-leak into the cooling system that is still sealing small leaks?
It seems like I read somewhere, that we should never use that stuff especially in a turbo car??
Ron

I removed the two factory hoses completely and connected to the engine hard lines directly. I did the bypass immediately after I noticed a small amount of liquid came out the driver's side floor vent. I haven't checked the firewall hose for liquid or blokage yet. I think I had similar symptoms to you though. Nothing to indicate a large consistent failure. I erred on the side of caution because I wanted to still drive it. It's been a year and other than a cool fall evening, I'm okay without heat for now until I have time to check it out or replace it.

[BLK BRD 88]

Thank you, everyone who contributed ideas & tech help!

Update:
Last 60 mile run into town a couple of days ago; the antifreeze leak was nearly constant, the windshield fogged up when I turned the defroster on, & we smelled antifreeze in the car for nearly the entire trip.

Today:
The heater core is now isolated, and the intercooler has new neoprene hoses with new heavy duty metal clamps around them.
Ron