I found out my cooling fan isn't working after getting my a/c worked on. The car hasn't overheated so I was assuming the fan was working but there was a problem with the relay. I replaced it, but it still doesn't come on with the a/c. My mechanic says it's an electrical problem and that it could cost from $60-$300 just to figure out where the problem is. SO... I had some gift $ on Amazon and the fan itself was fairly cheep so I just bought one....
Anyway long story short, I'm replacing it hoping that the problem is the motor on the fan itself and my question actually has nothing to do with the a/c, but with the upper radiator hose. I'm not exactly sure how the fan comes off...if it slides down in grooves, or just pulls away...but I'm assuming I have to slide it down so I'll need to move the upper radiator hose. I've never done any car repair (obviously) but I've been reading that I don't have to drain all the coolant...but I can't find any info on how much to drain or how to tell when I've drained enough so it doesn't come dumping out the upper hose when I disconnect it. Will I feel the hose lose pressure when it's empty enough to disconnect?
...OR is it possible to get the fan out (and new one in) without disconnecting the hose at all...by sliding it to the side. I'm just nervous about messing with the coolant at all. Thanks.

 

If you are worried about overheating, drain, flush, and refill the cooling system. It can't hurt. The upper hose isn't really the one you will have coolant coming out of. It's the lower...gravity. Water will go down.

 

x2

The entire coolant system should have about 2 gallons total (give or take). There's no problem with completely draining the system if necessary (obviously into a clean container at least 2 gallons in size).

Being that you don't want to have to do this again later on, I would recommend purchasing new coolant to replace, but not 100% necessary if it's been changed recently (within a year).

With removing the upper hose, you should only have to drain a little out (if any at all) to disconnect the hose from the radiator while leaving it connected to the T-stat. This should give you enough access to replace the fan...

I'm not 100% convinced your fan is the problem. Did you (or more accurately your mechanic) jump the relay to force the fan to come on?

Seems you already replaced the relay, correct?

There is a high and low pressure sensor within the a/c system which will deactivate the system if their parameters are off. Not uncommon for these sensors to go out. Easy fix with the right a/c tools, or for a local shop.

 

Thanks.

I kind of doubt it's as simple as changing the fan too, but I'm getting a new one for pretty much the cost of shipping so I figured I might as well try swapping it since it seems fairly straight forward, except for messing with the radiator hose...
The thing is the a/c DOES work, and the car hasn't overheated...the fan just doesn't come on. I did replace the relay. Would the sensor you're talking about just effect the fan, or would it deactivate the whole system so that no cold air came out at all or the blower wouldn't work? because if that's the case then that's not the problem. I know that he didn't jump the relay. He only replaced the condenser and charged it up. He said it worked fine for a minute and then got warmer, and when they checked the fan it wasn't on. ...so he said NOT to run it because the whole thing would burn out.
I didn't say before, when I bought the car the guy I got it from told me after the fact that the a/c needed fixing and he would do it for $200. (I hadn't even driven it before I bought it, let alone had someone look at it...and I KNOW, I KNOW...but I needed something that day, etc) Anyway, the title says it's a rebuild from a front end collision...and when I went to the mechanic he said "you don't even have an evaporator installed." ...so I'm kind of stuck with the idea that the evaporator got flattened (and prob the radiator and fan) and that the guy who sold it just got it in running condition. which would mean just fixing the radiator)
I think since I have a fan, I'll just swap it and hope it works, and if it doesn't I will jump the relay. (I'm sure it sounds stupid that swapping it sounds easier to me than jumping the relay, but I'm afraid of shorting something or wrecking the computer somehow)

Anyway...when you say I "you should only have to drain a little out (if any at all)" from the radiator...my question is "how do I know?"...I mean will I feel it in the hose? Hypothetically if I just pulled it off right now, would it be under pressure where a gallon would come gushing out, or would only the amount in the hose come out (gravity)? When I put it back on will I have to burp it if I'm not draining the radiator itself?

It seems like it's a lot less of an issue than I'm making it out to be, and at worst I'll have to bleed it, but like I said I don't know jack about cars and I don't want to get cocky 'cause I've read how to do it in theory.
Anyway...I'm changing it Thursday, so I'll probably be writing Friday about how my car is "suddenly" overheating all the time after having no problems at all.

 

Oh I understand, needs out weight 101 point inspections at times.

If the relay has been replace, then there's no need to jump it. Jumping the relay would only be done to test the relay. New = assumption of working correctly.

I'm no AC system expert, so take my advise as merely suggestions .

The switches I mentioned earlier will deactivate the "under hood" ac system, but the blower motor under the dash should still work (would blow warm/hot air). They deactivate to help prevent damage.

The fan not working could disable the system as well (depending on how the system works and what the system monitors). You might get lucky and replacing the fan actually fix the problem, but the main thing the fan does is provide extra cooling for the ac condenser (looks like a small radiator, usually in front of the radiator). Fans being so cheap like you mentioned, replacing it will definitely not hurt anything in the long run.

Sounds like you might need a complete AC system check-up if parts were damaged in an accident (even though some were replaced, others may have also been damaged - switches I was referring to for example).

Simply remove the radiator cap (mid-way in the upper radiator hose, between the radiator and thermostat housing - actually closer to the T-stat). This will allow for a visual inspection of the fluid level within the hose. If you take off the cap see no fluid, the upper hose is empty and there's no need to drain. If there is fluid under the cap, simply drain enough until you don't see any at the cap. Remember to keep the lose hose end up so not to accidentally drain out the fluid. Keep in mind, this isn't radio active, so a little spillage isn't the end of the world. Shop rags and a bucket should be all you need as a safety precaution. The system will be under slight pressure (15 psi is typical), but you shouldn't lose any fluid regardless. And if you do it'll be minimal.

You shouldn't have overheating issue as long as you don't use the AC... as hard as that is in the summer.

What you're attempting is level 0 stuff out of a range of 0-5, 5 being hardest. You can do it!

If the fan change doesn't work, let us know. Might be a wiring issue or something else that got beat-up during the accident.

 

whew. That's really what I wanted to know...that detaching the hose wasn't going to spew out the whole contents of the radiator (and from what I've been reading is the most toxic substance known)

RE: "you might need a complete AC system check-up" ...the a/c does work. Cold air comes out...I just don't want to run it without the fan on... I'm assuming it's the fan motor, or wiring.

anyway...thanks for the info about the hose. I'm less worried about being covered in flesh eating acid. (and thanks for not being critical of not having any idea about what I'm doing...)

 

Ah, the ac does work... bet the fan is the problem then (or could be the relay still, but very unlikely if it's been replaced already). If the fan doesn't work, you would experience cool air until the system has cycled a few times at which point it won't be able to exchange the heat out of the condenser (would work better at highway speeds), and might even add heat from the radiator.

Antifreeze is somewhat toxic, but the actual remedy for antifreeze poisoning is alcohol intoxication (getting drunk on beer/whiskey/wine/etc.). The alcohol will convert the antifreeze into non-toxic....

Don't drink it, but if it spills on your skin, simply wipe it off.

, you're very welcome! We all start somewhere... bet you know exactly what to do next time you run across as situation like this again (regarding radiator hose/fan swap). I'm just glad I could set you at ease a little.

 

Coolant is hardly "the most toxic substance known" in a car. Quite harmless really, unless you drink it or let a body part soak in straight antifreeze for a bit. Use common sense (quite uncommon these days), and you'll be fine.

 

So swapping the fan was no big deal...it took a bout 20 minutes to fit it in...but it still doesn't turn on. ...I've been using the a/c and obsessively looking at the temp gauge and it's only moved past the middle (where it's always been) once...and that was on a super hot day after sitting in a parking lot of Napa when I replaced the relay one more time. SO... I'm fine with watching the temp and only running the a/c on the highway, etc. ...but if there's any ideas on why the fan doesn't work after the relay, fuse, and fan itself were replaced I'd love to try. As I understand it, any sensors or the thermostat or whatnot shouldn't really matter since the fan should come on with the a/c right away.
anyway...like I said, it doesn't seem like a big deal to not have the fan, but if there's something I'm missing I will try it.
thanks -Sean

 

If the fan and relay were both replaced, then it could be the wiring between the two considering the Neon was previously involved in an accident.

I'm not sure if you know how to jump the relay, but that would force the fan to come on if it'll work. That would tell you if the problem is at the relay, or between the relay and the fan.