Author Topic: Is my 1.6TD Overheating? (Read 11899 times)

Doakster · « **on:** September 22, 2008, 02:57:42 pm »

Well here's the scope, would appreciate any suggestions.

My 1.6TD temp gauge seems to like to climb up on the temp gauge pretty quick when just sitting and idling.

I've had it up as far at the 3/4 mark, and it will keep rising if I let it.

What is the normal range from these motor, I would think it should never go past 1/2

This is an Ecodiesel, but only has one 2-speed fan, which I've checkout. I can get only one speed to function when jumpering out the connectors on the plug that goes to the radiator temp sensor.

Also my fan comes on as usual with the AC or the defrost on just like it should, some times I use that to keep it cool.

I've shot the radiator hoses and head with a laser temp gun and at about the 3/4 mark on the temp gauge, that equals about 150-160 at the radiator and about 180-190 at the head.

I'm guessing it's the radiator temp sensor that is out.

When do the water pumps usually go in these motors? And has anyone ever installed a lower radiator temp sensor to have the fan cycle on earlier? I don't see how that would hurt.

Also when should the coolant light come on?

Smokey Eddy · « **Reply #1 on:** September 22, 2008, 03:22:39 pm »

the coolant light comes on when over heating once it gets to the right hand side just past 3/4
shortly after you will cook the oil and the oil light will buzz
then your head will pop up and all sorts of hell breaks free.
do the "feel the top hose" test - start it up cold and feel the top hose to see how quickly it gets hot.
perhaps take the thermostat out and see if its opening all the way in a pot of boiling water. They are fairly cheap so you may just replace it if its not new already while you have it out.

As for a pump "going" I dunno you could look in the expansion tank and see how well coolant flows through there once it's hot.
Start it with the lid OFF and way for the thermostat to open to see if it starts flowing. If its just a trickle maybe the pump is hooped.

Smarter people with a billion times more experience than me will chime in though.

jtanguay · « **Reply #2 on:** September 22, 2008, 03:33:41 pm »

i think these cars normally sit just over the halfway mark... hopefully you don't have head issues! check easiest stuff first, such as... is the rad fan turning on? the water pumps are pretty bullet proof as far as i'm concerned, but things can happen. i got a really really hot t-stat from the stealer once... and my temp was rising like yours. rad would stay cold but car would be heating up... if i let it idle, there was enough flow to the rad to keep the temp steady... VERY frustrating. i'm glad i just bit the bullet and swapped t-stats. for a cheap one too :lol:

my temp gauge stays rock steady now that i've changed the rad thermoswitch, t-stat, and flushed TWICE. hmmmm nice black/brown liquid comes out!!! which CANNOT be good for transfering heat.

i've had a boilover before... due to the rad fan not coming on. DON'T let it happen to you!!! always verify the fan comes on when you get one of these cars as the ones with a/c are a weak point. all the water boiled out and then i had to fill it up with water to get me home. luckily there wasn't any damage. it happened while idling at the scene of an accident on the highway... while driving it would obviously not heat up because of the air flow

Doakster · « **Reply #3 on:** September 22, 2008, 03:37:42 pm »

Quote from: "Smokey Eddy"

the coolant light comes on when over heating once it gets to the right hand side just past 3/4
shortly after you will cook the oil and the oil light will buzz
then your head will pop up and all sorts of hell breaks free.
do the "feel the top hose" test - start it up cold and feel the top hose to see how quickly it gets hot.
perhaps take the thermostat out and see if its opening all the way in a pot of boiling water. They are fairly cheap so you may just replace it if its not new already while you have it out.

As for a pump "going" I dunno you could look in the expansion tank and see how well coolant flows through there once it's hot.
Start it with the lid OFF and way for the thermostat to open to see if it starts flowing. If its just a trickle maybe the pump is hooped.

Smarter people with a billion times more experience than me will chime in though.

I've actually run it to this point a few times and got no light, but I don't think my temps are that high based on my Temp gun test. It's only about 180 at that point at the head.

Isn't the stock Fan switch supposes to come on at 200 or so degrees? If so my measured temps at the radiator wouldn't be triggering the switch yet but my cluster gauge is telling me I'm hot.

The thermostat is located in the water pump correct?

Smokey Eddy · « **Reply #4 on:** September 22, 2008, 03:55:25 pm »

Yessir.
That fatty hose at the very bottom take it off and then take the plastic mount thing off it mounts to and the termostat gets wedged in that when you put it back on the pump. careful off the ring that comes out with it.

I had cooling problems (still do but due to cracks in head) and people told me that plastic piece gets warped sometimes so if you put it back together and it leaks from there don't be too upset but you may need to replace it. They aren't expensive and you can get a metal one i believe...

Doakster · « **Reply #5 on:** September 22, 2008, 03:58:01 pm »

Quote from: "Smokey Eddy"

Yessir.
That fatty hose at the very bottom take it off and then take the plastic mount thing off it mounts to and the termostat gets wedged in that when you put it back on the pump. careful off the ring that comes out with it.

I had cooling problems (still do but due to cracks in head) and people told me that plastic piece gets warped sometimes so if you put it back together and it leaks from there don't be too upset but you may need to replace it. They aren't expensive and you can get a metal one i believe...

Interesting...I've never seen a metal thermostat housing on a VW, but I'd sure like to.

the caveman · « **Reply #6 on:** September 22, 2008, 05:30:50 pm »

An idi diesel shouldn't get hot just idling. whenever i do coolant system repairs, i have to fast idle the motor to be able to get the fan to come on. Unlike a gasser, it takes patience to test everything from cold with a diesel. If yours is getting that hot that fast, there is a problem, whether it's your gauge, sender or something more expensive

Doakster · « **Reply #7 on:** September 22, 2008, 05:49:49 pm »

Quote from: "the caveman"

An idi diesel shouldn't get hot just idling. whenever i do coolant system repairs, i have to fast idle the motor to be able to get the fan to come on. Unlike a gasser, it takes patience to test everything from cold with a diesel. If yours is getting that hot that fast, there is a problem, whether it's your gauge, sender or something more expensive

I agree with you on this one... I'm going to try the sender first, something is telling me this might fix it based on the temps I have shown.

Doakster · « **Reply #8 on:** September 23, 2008, 05:05:14 am »

Quote from: "the caveman"

An idi diesel shouldn't get hot just idling. whenever i do coolant system repairs, i have to fast idle the motor to be able to get the fan to come on. Unlike a gasser, it takes patience to test everything from cold with a diesel. If yours is getting that hot that fast, there is a problem, whether it's your gauge, sender or something more expensive

So let me ask you...is the guage in the cluster replaceable or does the whole cluster have to get swapped? I'm guessing the cluster has to be replaced.

Doakster · « **Reply #9 on:** September 23, 2008, 11:40:33 am »

And here is my next question, where is the sender for the gauge located, and it's different than the main temp sensor correct?

Smokey Eddy · « **Reply #10 on:** September 23, 2008, 11:51:02 am »

There are so many i hate it!!!
and I have no clue!
i've tried to figure that one out my self because my gauge is wonky. i'll be checking this thread to see if someone knows

myke_w · « **Reply #11 on:** September 23, 2008, 01:52:18 pm »

Quote

I can get only one speed to function when jumpering out the connectors on the plug that goes to the radiator temp sensor.

That would be the first thing I'd look at.

Doakster · « **Reply #12 on:** September 23, 2008, 03:02:32 pm »

I agree I should look into that, just don't feel like plowing in the wiring harness but I know I would do it.

I'm still convinced by gauge is off.

autoholic · « **Reply #13 on:** September 23, 2008, 03:59:07 pm »

While we're on the topic of running warm, I was wondering if different fan switches (one on radiator) are available. My fan comes on at 190 at the rad, at that point the coolant overflow tank is just over 195 when checked with a thermometer , and I suspect the head is probably even warmer. I am currently using the stock Samurai coolant temp gauge, which has been living just over 1/2 to maybe 2/3 if really warm. If I jumper the fan on constant it'll stay under half no matter what I do. I want to keep it at like 180 all the time, i have a 180F Tstat, but if the fans do not come on till 190 at the rad, I think its a bit too warm, I don't like it. I have 2 10" fans and a Rabbit radiator, everything seems to flow very well.
I think I have seen a different water neck on cyl head that accept the fan switch there, instead of rad? do these exist? That seems much better.
Maybe I'm being overly critical on running around 200F, but running this warm has always bothered me, especially since this motor is a turbo'd NA.

Doakster · « **Reply #14 on:** September 23, 2008, 05:12:31 pm »

Yup hear are your options for fan switches, and i swear I've seen one that is for "extreme hot" climates that comes on in the 70 degree C range but I can't for the life of me find it, I just saw it the other day.

http://www.germanautoparts.com/Volkswagen/Jetta/Cooling/208/3

Author Topic: Is my 1.6TD Overheating? (Read 11899 times)

autoholic