Possibly need new heater core

[vskid3]

Did you end up trying to start the fan using a paperclip? My '97 Civic was having issues with the fan so we used a paperclip to make the fan run for a few months. One day for kicks, I tried plugging the switch back in and it worked fine. Maybe it hadn't been plugged in all the way or there was corrosion keeping it from working before.

If you're going to take your car to a shop, you're usually better off going to an independent one than a chain. Hop on Google and see which ones around you have great reviews. I'm lucky that the best reviewed shop in town is right next door for any jobs I can't do myself.

[TheEnemy]

Your fan is fine. When you jumped battery power to it and it ran confirmed that.

I have seen more bubbles, in fact I saw one that when I revved the engine a little it hosed me down with coolant.

There should be a thermal switch on or near the thermostat housing, pull the connector and jump the terminals on the connector, this will be low current so a small wire will be fine. You will have to have at least the ignition on, (some run even with power off). If the fan comes on replace that switch. They can fail intermittently which can make troubleshooting a nightmare.

My experience with PepBoys was when they screwed up they blamed the customer and said it needed something else.

Edit: The head gasket can cause low compression, and with the proper tools and experience can be changed in an afternoon. We did so on Ugly a time or two. Though I suspect the engine is just worn out as well.

[Xist]

I bypassed the fan with those 22g wires and the fan ran.
I jumped the switch (with a paperclip) and the fan ran.
I have replaced the thermostat, switch, and relay with new Honda parts. I have 12v into the relay box.

I did not understand how the switch worked, the cable supplies power, when the switch reaches temperature, it closes the loop, and the fan is supposed to run, so the second O'Reilly guy was wrong, the cable is fine.

Well, maybe.

I idled my car in the driveway for twenty minutes and checked the switch pins, thinking it was supposed to supply power, even though I should have realized that was not how it worked. I went to do an update and realized I should try again, but this time check for resistance, except when I came back there was a small puddle under my car and a crack in the seam at the top of the radiator. I do not know if it was there before, if there was too much pressure, it would have released from the heater core.

I turned off the engine, but kept the system on, and was about to short the cable, but thought to plug it in. Earlier today I just put in the clip and thought I would drive that way until I could figure it out, but knew I could do better. However, as I worked with it, I heard clicking.

That would be the relay.

I could not make it happen, so I tried my fateful experiment and attempted to accomplish the many vital tasks I need to complete before moving five hours away.

When I plugged in the cable, the cooling fan ran for just a moment. I pulled on it until the fan ran for several seconds, then unplugged it and used the paperclip.

Why would the wiring work with the paperclip, but only with the switch when pulled?

I am not excited about the crack in my radiator. It only released a fine mist.

For now.

[cajunfj40]

Originally Posted by Xist

I am not excited about the crack in my radiator. It only released a fine mist.

For now.

Hello Xist,

Can't offer much help on your wiring issue, not being equipped with any Honda knowledge. Only suspect would be a bad wire to clip connection inside the plastic connector that plugs into the thermoswitch.

As for the split in the radiator, welcome to the "Gee, I fixed problem X, only to find the next weak point in the system" club. My condolences. My situation was a leaking thermostat housing. Replaced that, got a split in the radiator. Replaced that, blew the lower intake manifold gasket (that was old and leaking anyway). You can "buy some time" (not a lot of time) by depressurizing your cooling system. I have tried two ways, and can think of a third and fourth.

First way is to loosen the radiator cap to the first notch - the point where it releases the internal pressure seal and allows pressure to get to the overflow tank. Messy, as the outer seal above the inner seal also comes loose, so you get some overflow out the radiator neck, too. I've tried this for a commute or two, and lost a lot of coolant to slosh.

Second way is to get one of those "lever-release" type radiator caps, and either wire the lever up (if there is room for it with the hood shut, I did not have room when I tried it) or shim the lever base up so it depressurizes the system. This is what I did, it sort of worked. Kept spitting the shims out, though, so I probably only somewhat reduced the pressure. The radiator still dribbled from the crack, but it wasn't bulging at least, and did not "blow out".

Third way is to get or make a "blank cap" that has no inner seal, just an outer one to the radiator neck. You might be able to just drill out the itty-bitty "return valve" in the middle of the radiator cap's lower seal. This return valve is what opens when the cooling system pulls a slight vacuum upon cooling down and allows drawing coolant back in from the overflow tank. A small hole is all you really need to dump pressure.

Fourth way is to get a super-low-pressure radiator cap. This isn't as good as no pressure, but it is likely more available and requires no other mods. 6 PSI seems relatively available, which is ~10 psi less than most factory caps.

The idea is to run your cooling system open to the atmosphere via the overflow tank. This will reduce the stress on the split in the radiator, causing it to bow out less, grow slower, and not spit as much coolant. You'll lose the boiling point raising effect of a pressurized system, so this won't work for high load or extreme heat situations. It should limit the leak rate enough that you can "limp along" to a point where you can replace or repair the radiator. Do keep an eye on coolant level and temp, though. Don't want to turn a simple radiator leak into a cooked engine.

Note: make sure your overflow tank does not have a tightly sealing cap, else it might blow off. If you cannot find where it vents to atmosphere, check it a few times during driving to make sure the cap hasn't blown off. If it does, you may need to make a larger vent hole in the overflow cap, that you can later plug with a screw after you replace the radiator and go back to running a pressurized system.

[JockoT]

I once split a radiator top hose. I removed the radiator cap, topped up with water. then drove 10 miles to the nearest dealer. Never lost a drop of water. Bought my new hose, drove home. Same result. Changed dose, topped up, cap back on and back to normal. Without the cap there is no pressure. Coolant still gets up to 212 degrees.

[Xist]

A "Standard"-quality radiator is $56 shipped from Rock Auto. That would need to wait until my second paycheck from the new job, but should be fine.
Maybe the crack was already there, a couple of times I found coolant on top of the radiator and when I first pressure-tested it, I heard hissing from around the opening, but it did not seem to be the worst problem, so I did not try to track it down, although I did not notice anything of the sort the second time I tested the pressure.

[TheEnemy]

Making progress yay. Yeah I know it sometimes sucks but now that you know these problems they can be fixed.

Does the switch have one or two connector pins on it?

If it has one it will control ground, and if so something is loose and not making contact. It could be corrosion as well. If so when you pull on it you pull on whatever is loose and it makes contact.

If it has two it would likely (since you already replaced the switch) be a bad connector. if you can take a picture of the end of it looking into the slots I might be able to help you jury rig it, maybe even fix it. But most likely it will have to be replaced which will require splicing in a new one and the part stores are often proud of their connectors. I payed $20 for one on my Jeep recently.

[Xist]

I do not know if you can really see it, but it is round with four holes, two being for the clip, and two being for the leads. I should be able to bring in my old switch or ask them to grab one of theirs and see what they can match to it.

Or call Honda and at least get a part number.

[TheEnemy]

I cant really tell from that photo, how do the wires look on the back side, any kind of fraying or still solid with the insulation?