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General Information => Troubleshooting => Topic started by: shari on June 24, 2009, 06:27:07 pm
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So hi I really need ya'lls help. Im in new Mexico on my way to north Carolina and am needing your collective minds. Here is the tale. So I on tuesday I stopped for the night and I had been checking my fan periodically and it seemed intermittant and all wire connections in the car that could jiggle lose pretty much had. So when checking I fooled with the connection at the thermo switch and the fan came on. I restripped the wires and reconnected them. Drove for a half hour the next day, and stopped to check the fan. Wasn't on and then coolant started spraying out the expansion tank. While waiting for a tow I checked the fan fuse and realized it was blown and that I had probably reversed the connection. So I got towed to a parts store and have ordered a tank, thermo switch, and thermostat to be safe and have looked at some things in the two days I've had to wait for the parts. The coolant is circulating, there is no
Oil in coolant or vice versa, there is a very small amount of bubbles (hardly any) in the expansion tank while running, I can hotwire fan both at fan and switch and it works. So my questions: do you guys think that if I put the new tank in and thermo switch that I can keep driving? Is it just the fact. That I stopped and didn't have the extra wind blowing through the radiator that the expansion tank burst? Thank you. So much for your help. I really need it and appreciate it. Oh by the way in weld does not
Work on your expansion tank.
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If the t-stat is failing I don't think the fan will come on since no hot water will get to the thermo switch in the rad. Good luck, let us know what happens :)
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hi. i checked the hoses and the radiator and the were warm. i wasnt sure how long to run it to do that and was scared of running it too long in its condition. the top hose was warm.
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If you have bubbles in the expansion tank when the car is running you have a blown headgasket.
You can try and limp it home, but you risk damaging the engine. When you are moving the fan pretty much never comes on.
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Won't a blown HG with that symptom also cause high running temps?
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i dont have a temp gauge. it near one
hundred degrees outside. would just a few tiny
bubbles be enough to indicate a blown head
gasket? whay would the expansion tank start
spewing before my eyes after i stopped if it
wasnt fan related? thanks a lot.
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please? :'(
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Without a temp gauge it's hard to know if it's boiling over or if it's a blown HG.
I see no need to change the tank unless your's is cracked.
If you can hold your hand on the top rad hose for 10 seconds with the engine all the way hot then it's not overheating, if it burns you before you can take your hand off it is too hot.
it near one
hundred degrees outside.
I guess you probly get burned just touching the bumper too though ::)jk
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i guess i didnt explain that the expansion tank actually
busted a seam. and yeah the hose gets hot. doesnt burn my hand i am actually
getting a little
more worried now after reading more stuff
about the headgasket. like would the coolant
really bust a seem like that just cause the fan
didnt come on? and there is blowby and once
on this trip the can wouldnt s/ectrical but also running on oil? i so badly dont
want it to be the headgasket cause i got 1300
miles to go and am in the middle of no where with one parts
store and no diesel mechanic. so...thanks for
your replies.
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When I drove a car through Arizona-Nevada, the car overheated from the thermostat getting stuck shut. The engine got so hot that coolant spewed from the radiator cap due to the extreme pressure. I would think that your radiator cap should have released the pressure before the expansion tank burst. A stuck thermostat could cause an overpressure situation in the cooling system.
Try to flush the radiator with water at least to make sure its not clogged and use at least a 50% water 50% antifreeze mix. Don't use staight antifreeze. Maybe a new radiator cap would help. Goodluck.
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a few bubbles in the expansion tank isn't serious. my old car did that and was fine. its from the small line going to the tank, it pours right in and creates a couple of bubbles. if its building pressure very quickly from a cold start, then its a blown head gasket. looks like you also need a new expansion tank cap as the one you had before wasn't releasing the pressure early enough. this is to prevent damage to hoses and other parts like the heater core :o and you want to protect that heater core ;D. i believe there was even some kind of recall, or new part because of all the old ones failing. something about a blue expansion tank cap???
if your radiator is getting hot, then i doubt its a stuck t-stat, although they sometimes can flow a little coolant, but not enough. to limp it home i would suggest looking for a coolant temp gauge to tee in somewhere, as it will be your first line of defense. you can use the heater to help reduce the temp if needed. but because your car only overheated after coming to a stop, i feel that your t-stat is opening properly and the rad is doing its job.
so if you can't install a coolant temp gauge, then make it a habit to make sure the rad fan is coming on if you stop, or if not turn on the heater blower to max on heat. i had to do this once on a hot day, maybe not as hot as you though... but i survived :D i also used a product called tow cool. it says its compatible with regular coolant so i poured it in. immediately i saw stabilization of my temps and they wouldn't rise as much if i was going uphill.
hope you have a safe trip home!
edit: you probably already know this, but make sure to keep lots of water in the car :) if you use tap water or anything other than distilled/reverse osmosis, then be sure to use a rad flush in the future.
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Worst case is you put in some block sealer if it is a blown gasket with only a few bubbles. I would then hot wire the fan and let it run all the time. I do that in hot rods all the time. Came home from Florida and then changed the gasket and did a top end rebuild. Good luck!
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Worst case is you put in some block sealer if it is a blown gasket with only a few bubbles. I would then hot wire the fan and let it run all the time. I do that in hot rods all the time. Came home from Florida and then changed the gasket and did a top end rebuild. Good luck!
if you hotwire the fan to run on high speed mode, beware that the fan motor WILL fail. the high speed mode is only meant to be ran for maybe 1-2 minutes or so max.
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Worst case is you put in some block sealer if it is a blown gasket with only a few bubbles. I would then hot wire the fan and let it run all the time. I do that in hot rods all the time. Came home from Florida and then changed the gasket and did a top end rebuild. Good luck!
if you hotwire the fan to run on high speed mode, beware that the fan motor WILL fail. the high speed mode is only meant to be ran for maybe 1-2 minutes or so max.
I think at least a simple toggle switch spliced in the car so you could at least turn it on and off and you really should get an aftermarket temp gauge to see where the temp really is. As far as the fan running constant they are on when the AC is on anyway but I wouldn't want it wired constant. As far as the tank busting, that had to be caused by the relief valve in the cap not releasing which they are known to do from gunk getting up inside the rubber gasket where the little valve is no matter what caused it to overheat in the first place. I definately wouldn't reuse that cap the way it is because you will probably end up with the same problem. If you can't get a cap then just put it on loosley enough to just stay on. There are a lot of aditives today to help keep the engine temps down a little like was said in a previous post and I would use one, which ever they have at your parts store that they recomend, every little bit helps in this situation. If you just have a few little bubbles that in itself should be ok. You seem to have multiple problems but you have to have a new tank and cap, at least a cheap temp. gauge and a toggle switch to turn the fan on when it starts climbing too high, you should only need it if you are idling or on a long pull. T ;)he heater idea is also very good and it helps a little bit. Please check back with us to let us know how you are making out. Good luck and I hope you can keep going, make sure you have enough water like a previous post also said and plenty for yourself too if needed. And last of all don't use The A/C if you have one or put any more load on the engine than you have to till you know how for sure how it's going to hold up. Put your parts on and drive around where you are for a while in case you need something else you will beclose to the store. You should know pretty quick if it's gonna heat up or not. You never said what kind of car it was but it sounds like the motor is about gone and I wouldn't spend a fortune on it getting a emergency rebuild or something like that, it would be too expensive and probably not hold up long anyway.
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Do you have a/c and does it work? A/C system problems can affect the fan operation.
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Do you have a/c and does it work? A/C system problems can affect the fan operation.
We still don't know what kind of car it is but if it's a bad or weak relay are they interchangable in the MK2's and later like the old Rabbits and Jettas MK1's are?
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Do you have a/c and does it work? A/C system problems can affect the fan operation.
good call on the a/c. they can actually cause the rad fan to quit working due to thermal load/stress. the only reason that the fan can continuously run with a/c is due to the resistor. even on low speed i dont think the fan would last long, as it was never designed for it, and thus the reason for adding the resistor.
also, an mk2 rad fan (and most others) working intermittently is a sign that it is slowly dying. dealer prices for the fan are outrageous, so junkyard ones are your best bet. if you have no intention of keeping the a/c, then get the fan from a car without a/c. you will know that you can trust that fan because theres a 99% chance that it will work, and work for a long time. i've never had an mk2 non a/c rad fan die on me, and i've had 2, and the one car i get with a/c, the motor blew. heck i even attribute it to having damaged the engine because it was overhauled, but they didn't even bother bringing the cooling system up to spec. very sloppy work IMO.
heres my rundown on what probably occurred - very hot day, a/c is on. rad fan always on, but kicking into high speed mode frequently to keep the a/c cool, or to keep the engine cool. eventually the fan will say no more, and quit functioning. the worst part is that vw never introduced a failsafe for rad fan failure. so the rad fan begins to fail. the a/c system was empty when i got it.. gee i wonder why? the thermoswitch was probably trying to turn the fan on high speed, but it wasn't responding, so the gas got too hot and pissed right out of the seals! next the engine temp was climbing, and so the a/c was cut (the only reason the compressor didn't get shot) and tried kicking the rad fan on, but no dice. this is where the beginning of the end occurs. by the time the driver realizes that the coolant gauge is way over to the red, its too late. one other thing i noticed after replacing the condensor with a new one, is that there was almost what looked to be a nest between the condensor and radiator. after cleaning that out, i noticed that the car ran cooler from the extra airflow. this could have been another reason for the frequent switching to high speed fan mode.
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Make sure you have water circulating through the little hose and into the top of the coolant tank.
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I finally got rid of all my a/c wiring after I was having fan issues (the a/c was inoperative since I bought the car). It's so simple now, I love it! Tested the fan the other day by running the car hard until it got hot - fan cut in exactly when it was supposed to. :D
If you want to bypass the a/c circuit to prevent overheating and you know your fan works (by jumping the thermoswitch) and hopefully your thermoswitch works, do this:
-connect the red wire that normally goes to the relay directly to the red wire from the thermoswitch
-connect the red/white wire from the thermoswitch directly to the red/white wire from the fan
-connect the red/black wire from the thermoswitch directly to the red/black wire from the fan
-connect the brown wire from the fan to a ground or negative battery terminal
The red wire must go from the loom by the battery directly to the thermoswitch. Bypass the series resistor. Do not turn on your a/c if it's still got pressure or you will blow seals and possibly damage your compressor.
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Do you have a/c and does it work? A/C system problems can affect the fan operation.
good call on the a/c. they can actually cause the rad fan to quit working due to thermal load/stress. the only reason that the fan can continuously run with a/c is due to the resistor. even on low speed i dont think the fan would last long, as it was never designed for it, and thus the reason for adding the resistor.
also, an mk2 rad fan (and most others) working intermittently is a sign that it is slowly dying. dealer prices for the fan are outrageous, so junkyard ones are your best bet. if you have no intention of keeping the a/c, then get the fan from a car without a/c. you will know that you can trust that fan because theres a 99% chance that it will work, and work for a long time. i've never had an mk2 non a/c rad fan die on me, and i've had 2, and the one car i get with a/c, the motor blew. heck i even attribute it to having damaged the engine because it was overhauled, but they didn't even bother bringing the cooling system up to spec. very sloppy work IMO.
heres my rundown on what probably occurred - very hot day, a/c is on. rad fan always on, but kicking into high speed mode frequently to keep the a/c cool, or to keep the engine cool. eventually the fan will say no more, and quit functioning. the worst part is that vw never introduced a failsafe for rad fan failure. so the rad fan begins to fail. the a/c system was empty when i got it.. gee i wonder why? the thermoswitch was probably trying to turn the fan on high speed, but it wasn't responding, so the gas got too hot and pissed right out of the seals! next the engine temp was climbing, and so the a/c was cut (the only reason the compressor didn't get shot) and tried kicking the rad fan on, but no dice. this is where the beginning of the end occurs. by the time the driver realizes that the coolant gauge is way over to the red, its too late. one other thing i noticed after replacing the condensor with a new one, is that there was almost what looked to be a nest between the condensor and radiator. after cleaning that out, i noticed that the car ran cooler from the extra airflow. this could have been another reason for the frequent switching to high speed fan mode.
My Rabit had some aftermarket a/c system on it when I got it. I ended up taking all the stuff out under the hood but left the inside stuff alone and now when you turn it's switch on you have the fan on the engine anytime you want it or the blower from the aftermarket system too in the car with a different posiition, it worked out pretty good especialy in stop & go traffic on the highway, it's amazing how much you can cool it down with that switch. ;D