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Hello forum members, was looking for insight into what the two "copper" type pipe holes are in this picture. I was laying behind the passenger front tire for this underbody picture. These two exit holes appear to be directly under my evaporator (car has A/C). Are these A/C drain tubes....if not, what are they? Thanks.
Hello, they are the inlet and outlet for the heater core. Your heater-hoses from the intake manifold and water-pump attach to them. Regards, LowSporty
Many thanks. This summer, I had a belt issue that fortunately did not leave me stranded but did result in a belt fraying and then impacting the other belts. As I was pulling into the garage, there was a large discharge of clear, no-odor fluid under the right front portion of the car (picture attached).....this liquid dried fairly quickly and left no stain on the garage floor. I assumed it was due to strain put on the A/C system. I checked the coolant level and re-filled. I went through the brake fluid and replaced - I knew it wasn't brake fluid, but figured I'd do it anyway. I'm still not sure what this liquid was, and based on your comment is sounds like it wasn't refrigerant discharging from the system? I've since driven the car many times, with no issue, but I have not put the belt back on the A/C system yet. Any thoughts?
Your heater-core has been disconnected probably due to leakage inside the cabin, passenger-side front floor. The hoses are usually joined together with a 3/4" to 5/8" coupling to form a "loop" so the coolant goes in a circle and flows back to engine. If you had a belt problem [water-pump belt] the car probably over-heated and spewed coolant-water out the overflow. It sounds like someone was running pure water instead of the proper 50/50 water/ anti-freeze. Regards, LowSporty
Last edited by LowSporty; Jan 2, 2023 at 11:25 AM.
Your heater-core has been disconnected probably due to leakage inside the cabin, passenger-side front floor. The hoses are usually joined together with a 3/4" to 5/8" coupling to form a "loop" so the coolant goes in a circle and flows back to engine. If you had a belt problem [water-pump belt] the car probably over-heated and spewed coolant-water out the overflow. It sounds like someone was running pure water instead of the proper 50/50 water/ anti-freeze. Regards, LowSporty
Excellent, thanks. Sounds like this could have led to a real problem if not fixed, as I suspect this means no coolant was getting to the engine. Given I've driven it since, I'm surprised there have been not further issues but I hope I haven't done any damage to the engine?
At this stage, corrective actions are to reinstall the proper coupling, drain the radiator and refill with the proper mix. Anything else I'm missing?
Your problems are un-related. If the heater-core is by-passed, leave it be. You will just have no heat. If you repaired the belt problem your good. Open the radiator cap, what color is the liquid, totally clear means water. Drain and re-fill with 50/50 mix of water and anti-freeze Greenish/ pinkish means it's mixed with anti-freeze. Leave it be. You have to understand how this system works no offense but it sound like you don't! If the heater-core is by-passed it's for a reason! DON'T re-connect it! If you don't know what you're doing find someone who does, dicking around just causes more problems and/or damage! I hope this clarifies your situation, LowSporty
Last edited by LowSporty; Jan 2, 2023 at 01:21 PM.
I don't know the inner structure of the A/C box but this could have been A/C condensate. Had you been operating your A/C and was it kinda humid that day?
Your problems are un-related. If the heater-core is by-passed, leave it be. You will just have no heat. If you repaired the belt problem your good. Open the radiator cap, what color is the liquid, totally clear means water. Drain and re-fill with 50/50 mix of water and anti-freeze Greenish/ pinkish means it's mixed with anti-freeze. Leave it be. I hope this clarifies your situation, LowSporty
When this occurred, I replaced all belts, so the belts are good. I also refilled the radiator with the proper mix, so it is now greenish. Not to belabor the point, but just for my learning and understanding, why would the heater core be bypassed, and if it is, why would the liquid still have drained from the open tube in my first picture?
I don't know the inner structure of the A/C box but this could have been A/C condensate. Had you been operating your A/C and was it kinda humid that day?
That's originally what I thought, but after getting under the car and seeing these open pipes I figured something discharged from them. I have not put the AC belt back on.....I replaced all belts but decided to leave that one off for now, mainly because I didn't want to harm the AC system. I'll probably put it back on this spring and run the car just to see what happens. May also have it checked for leaks at an AC auto repair shop.
When this occurred, I replaced all belts, so the belts are good. I also refilled the radiator with the proper mix, so it is now greenish. Not to belabor the point, but just for my learning and understanding, why would the heater core be bypassed, and if it is, why would the liquid still have drained from the open tube in my first picture?
I told you, the heater-core was by-passed for a reason, probably it leaked, The liquid discharge DID NOT come from these 2 copper pipes! Your car over-heated from the issue with belt not turning the water-pump! AGAIN, if you don't know what you're doing, find someone who does!
...why would the heater core be bypassed, and if it is, why would the liquid still have drained from the open tube in my first picture?
Two main reasons: 1) it leaked and the previous owner didn't want to tackle the job of replacement (highly common); B) the general constant heat to the interior was undesired, so bypassing it eliminates this mini-radiator.
The heater core would be pretty difficult to drain completely by just disconnecting it, so will have old coolant/water in it. Unless the core is tipped or the car stopped very abruptly, the liquid wouldn't come out on its own.
Two main reasons: 1) it leaked and the previous owner didn't want to tackle the job of replacement (highly common); B) the general constant heat to the interior was undesired, so bypassing it eliminates this mini-radiator.
The heater core would be pretty difficult to drain completely by just disconnecting it, so will have old coolant/water in it. Unless the core is tipped or the car stopped very abruptly, the liquid wouldn't come out on its own.
Normally there will be 2 hoses running from the motor to those tubes. A 5/8" & a 3/4". One of those likely has a valve in it. There is hose nipples on the intake manifold and water pump. Bet if you trace the hose it's running a loop between them, bypassing the heater core. Doesn't harm anything. As mentioned in prior post, core was probably leaking and owner didn't want to deal with it. Not an easy job to replace it. An AC repair shop can pressure test the heater core to see if it's good or bad.
I'm Sorry, if I was harsh. I'm a retired mechanic of over 30 yrs. and although I don't know every thing I do know a liitle! Regards, LowSporty
I'm not offended, I appreciate your replies. I wasn't understanding initially when you said the problems weren't related, so just had to slow down and re-read. I enjoy learning and also getting my hands dirty, although I know my limitations.
So far, I've done oil changes, tire rotations, rebuilt the parking brake, put on new calipers and brake pads, changed the brake fluid and put in new steel lines and changed the power steering fluid. This plus the updates to the engine belts and radiator fluid.
I always feel like there's something "else" I should be doing. The engine belt issued happened after I recovered from a torn ACL (left leg, so couldn't use the clutch for nine months). I was so excited to drive it again I didn't inspect the engine, and low and behold worn fan belt blew out. I've been trying to figure out what the issue was and when I saw these open pipe holes, I thought I discovered it. That said, your input put my mind at ease that I did all the right things (changed radiator fluid, obviously updated all belts), so all's good.
Good for You! Better than paying someone else $80/hr. or up for simple, basic maintenance. If you gotta' clutch, you gotta 4-speed, like my '78 and you're O.K. in my book! Keep it Up and if I can help in the future, just ask. Regards, LowSporty
Last edited by LowSporty; Jan 2, 2023 at 05:06 PM.
Part identification - photo below
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