Possibly need new heater core

[freebeard]

There ya go. It will be just like driving an old Beetle with rusty heater cables.

[redpoint5]

Originally Posted by freebeard

There ya go. It will be just like driving an old Beetle with rusty heater cables.

My Beetle gave me exhaust when I wanted heat. Exhaust to air heater core is a bad idea.

[freebeard]

That was what they call the 'fresh-air' engine, because it didn't supply actual engine cooling air loaded with oil fumes to the heater boxes.

[Xist]

Originally Posted by Xist

Supposedly we never got below freezing last year, but it would be easy to drain the radiator and replace with 50/50. So, one of these and two hose clamps?



Coolant has a higher boiling point than water. At least it keeps getting cooler outside!

I did not need to purchase clamps, I just used the ones on the hoses going to the heater core. Removing those hoses was incredibly difficult because the clamps pointed downward, but I could not do much with normal pliers. I tried finding longer pliers, but Home Depot only had needlenose pliers and I was concerned those would bend the clamps, but 90° needlenose pliers should have worked perfectly. The only long pliers I found were 45° behemoths. I thought they would be great because I could pull the hoses from an angle and have the drip pan underneath, but there was not nearly any room for that. I found some large pliers that were not as long as I wanted, but still difficult to maneuver in there.

Curiously, I had especial trouble with the passenger-side hose. It was short, connected to the bracket, with a cable that seemed to open a valve in the heater core. It was easy to remove the hose from there. Then the shorter hose came out. It seemed to take forever, but coupling the two hoses was easy.

I have not tested pressure yet.

A friend from Church told me to run the AC and see if both fans came on. Only the condenser fan ran. I thought I was finally okay to drive last week (before I finally bypassed the heater core) and Chorizo drove forty miles on the highway perfectly, even running the air conditioning the last several miles, to see how hot the engine would get, and if the cooling fan would run.

It didn't.

The temperature was fine, though.

The next client was several miles away, 45 MPH speed limit, and light traffic. Everything was fine until the mom rescheduled.

Then my car overheated. My phone died, too.

I went back to driving my Accord, but I still have not found a resonator. I have everything else.

I thought the thermostat was bad, but I had not realized how slightly they opened. I replaced it with a new one from the dealer anyway.

I used test wires to run the fan directly from the battery. I bypassed the fan switch with a paperclip and it ran. I checked all of the fuses with a tester and they are good. I followed the instructions in this video and learned my new test wires were already bad:

https://www.youtube.com/watch?v=ire7vyDqelg

The relay clicked and my multimeter showed 0.5 Ω. In the video, the good one was 0.01 Ω and the bad one was 1Ω.

I bought a new one.

It was also 0.5 Ω.

The friend told me to make sure the relay box is putting out 12v. A mechanic on YouTube said you cannot put probes into the relay slots and suggested wrapping wires around each connector, securing them with electrical tape, and then using your multimeter on the wires.

My multimeter showed 0.

I was able to put my probes into the slots, but my multimeter still showed 0.

When I drained the coolant before replacing the thermostat I siphoned it out of the overflow tank, which was surprisingly full. I did that the hard way, the tank just slides out. I read the overflow tank fills when the engine overheats. I wonder how much of my missing coolant has gone there, but where has the rest gone?

[TheEnemy]

Is this what your under hood fuse box looks like?

Part 1 -Under-Hood Fuse/Relay Box (1996-2000 1.6L Honda Civic)

Also you said your new test wires were no longer any good, what did you mean by that... were they burnt up, if so what guage wire did you use.

[Xist]

TheEnemy! Thanks for responding! Yes! That looks just like my fuse box! I tried to figure out how to test the box, but I did not find anything. I might just purchase a cheap relay, get rid of everything but the terminals, but there must be a cheaper method.

I connected the test wire from the battery to the fan and it ran, but the wires were crazy warm, and the next time I tried to use them they seemed to be dead. I reconnected the fan to the battery and it did not start. 22 Gauge: https://oreillyauto.com/detail/dorma...00/honda/civic

These still work, they are 20 gauge: https://oreillyauto.com/detail/dorma...00/honda/civic

I finally picked up the last part to fix my Accord (and hopefully have turn signals again!), but there is a big hole in it. The Civic finally held pressure once bypassed the heater core and topped off with distilled water. I wanted to see if at least it would maintain its fluids. I drove over twenty miles and everything was fine, but suddenly she started overheating. I got off the freeway, parked, popped the hood, and topped off half an hour later before driving slower to my client's house.

The radiator fan never turned on.

I do not feel I have time to try to figure out Chorizo's electrical problems, so I took it to a Pep Boys near me.

They said the fan ran perfectly and they ran it for over an hour, but she never overheated. They said they did not fix anything, so they will not charge me, which is nice.

[TheEnemy]

So that last run you were freeway speeds when it overheated.

I don't trust what Pep Boys told you, I haven't had much luck with their work in the past. Did you see the fan running? You said it had more than one, AC and it stayed cool with the AC on?

22 gauge is way too small, its best to use 16ga for the fan, 20ga.

I'm still thinking fan, could still be thermostat (sticking), slow leak only under pressure, weak cap, or even a bad pump, I saw one that would work for a little, then quit for a little. Is there any smoke coming out of the tailpipe, have someone follow you, and what color is it if it is.

My wife had one where the ECU quit giving the command to turn on the fan, unless the AC was on.

After doing a bit of research it seems that the most likely culprit is actually the head gasket is starting to fail, it has been talked about in a few forums as starting off with what you are experiencing.

https://www.civicforums.com/forums/3...reference.html

[Xist]

Originally Posted by TheEnemy

So that last run you were freeway speeds when it overheated.

Yes

I don't trust what Pep Boys told you, I haven't had much luck with their work in the past. Did you see the fan running? You said it had more than one, AC and it stayed cool with the AC on?

They replaced the timing belt on my Forester and a week later the engine suddenly ran roughly. They said I needed a valve lash and wanted $125 to replace the spark plugs and wires. I changed the plugs and wires in their parking lot and came home to ask the fine members on here what they thought.

The car drove worse after they messed with it.

I ended up going to a different Pep Boys, having their store manager look at my car, and he told me to go back and make sure the belt did not slip a tooth.

They said the tensioner broke, but it was under warranty.

If they tell you you need a repair and they are wrong, do they say "My bad?"

The clutch went out on my Civic when I was trying to leave town and my insurance took it to a third Pep Boys. They did a good job, but something was still strange about the experience.

22 gauge is way too small, its best to use 16ga for the fan

Like these? All that I saw at O'Reily were the two sets I bought, although Fry's electronics has tons of them, but I had a horrible time finding ones for my multimeter. https://www.amazon.com/SE-TL4-36-Gau.../dp/B01L1JG32M

I'm still thinking fan, could still be thermostat (sticking), slow leak only under pressure, weak cap, or even a bad pump, I saw one that would work for a little, then quit for a little. Is there any smoke coming out of the tailpipe, have someone follow you, and what color is it if it is.

I will do that when I can.

After doing a bit of research it seems that the most likely culprit is actually the head gasket is starting to fail, it has been talked about in a few forums as starting off with what you are experiencing.

https://www.civicforums.com/forums/3...reference.html

I hope not! However, the engine has low compression, and rebuilding seems to replace the head gasket and do the rest of the work, but I would rather find an HX with fewer miles, or purchase a... Prius...

I was supposed to drive to Page, AZ to check out a job offer there, but I really did not want to. Instead, I walked to Pep Boys, picked up my car, drove thirty miles (in a much smaller loop, never 20+ miles from home), and she never started overheating, but it was almost nice out. I nearly enjoyed the walk. I think it was 86° when I left.

Still, I think the fan should have been on, but it was not.

I have spent as much time as possible trying to find another speech job down here that has more hours. Almost everyone says that if you can start the fan by providing direct power and by putting a paperclip in the switch, you need to replace the switch. This guy diagnoses the switch itself with wiring he bought from a junkyard for $6. I couldn't find the plug itself anywhere and it was late Friday afternoon, so I would not be able to try to find one until Monday. I was tempted to purchase one from O'Reilly or Autozone, but those do not always work, but if it is good and the fan still does not work, then I can return it.

How do I know it works, but something else is wrong?

I searched for the part number and a discount dealership popped up. Majestic charged a little less, but with shipping, it was not much less than my nearest dealership. I called and they said they would have a shipment this morning, so I placed an order on-line, but didn't wait for them to fill my order, just said I ordered on-line, and asked if they had it.

It requires a 24mm socket, deeper than normal, so I bought one, and the fan still did not turn on. Not when I turned on the air conditioning, and not when the water started boiling out of the radiator.

I am pretty sure the fan should come on

It wasn't like this guy:

https://www.youtube.com/watch?v=7UyhjT7nWY0

There was steam coming out and everything.

New Honda 180° thermostat, switch, and relay. Do you know what? i will put in a new fuse just for good measure. It is adding up, but still less than one hour of labor.

When the radiator was boiling, the radiator fan connector was only putting out .01v, so the O'Reilly guy said to unwrap the wire bundle and find the short. The guy from the other O'Reilly kept trying to sell me a fan.

Well, I had planned on waking up in less than four hours and driving 530 miles. We will see how that works out.

Fun. It is actually further than that...

Thank you very much for your input! Have a great day!

[JockoT]

Do you get power to the fan (12v)? If Yes fan is faulty. If No supply is faulty. Switch grounds fan relay. If you get 12v at the switch with the switch open, relay coil in intact. If you never get 12v at the switch, relay coil is open circuit. Coil should be on a separate circuit from the fan fuse. If coil in intact either fan fuse is blown or relay is not making. A defective relay is a very common fault. Check the fuse box. There may be a similar relay in the box that you can temporarily substitute to confirm my diagnosis.

[freebeard]

Is there a Pep Boys in Page, AZ? If not you need to move there.

I'm driving a water-cooled car for the first time in 50 years, and your travails aren't helping my confidence. For the time being, the Dasher runs cold. It needs a radiator shroud and/or grill block.