My patience is running out. (overheating issue)

[The Mad Hatter]

Like the title, my patience is running out with this car.  My supposed fuel savior is quickly becoming a money pit.  My most recent posts have been dealing with an alternator issue, which a new one resolved.  Now, its overheating.  I replaced the coolant level sensor, fan thermoswitch, lower radiator hose, and thermostat (upgraded to 180 degree from stock).  According to the gauge, its sitting just on the hot side of the light in the gauge, and the light occasionally comes on.  When i drained the radiator the fluid looked kinda greasy, and the sensors had some kinda sludge on them.  So what is it now?  
Thanks for the help in advance.

[jimfoo]

Have a stock oil cooler?

[jtanguay]

the gauge could be off too.  i bought one of those infrared thermometers.  money well spent  :wink: as you can check turbo temps, head temps, hose temps, etc  

also did you test the t-stat??? i bought one from c-tire that said 192F and was more like a 200F or more!!!  needless to say, i ALWAYS check my t-stats now!

have you flushed the system???  a good flushing with something like prestones heavy duty coolant flush is a good idea.  follow the instructions and don't go nuts on it because some of that stuff may harm the engine if left in for prolonged periods.  a good flushing in my car did the trick for me.  i get sooooo much heat its great, and she never overheats!  if the P/O (or yourself) used non distilled water, then it should be flushed right away, as it not only lowers the boiling point of the water, but it does a nice job at creating deposits in the engine.

the coolant flush will help clean the oily residue out of the coolant, but it will surface again.  i had my oil cooler go on me and was giving me lots of trouble.  oil level would go up, coolant down, etc.  i had a nice oily residue in the coolant bottle as well.  what i think was happening is that once the car was shut off the coolant pressure leaked into the oil.  good thing i caught it when i did because bearings need their oil!  the job is a PITA!!!! its those hose clips on the oil cooler.  if you don't have a/c its much easier.  those lines were knuckle busters! (stubborn me because i had just charged my a/c system  :roll:  :lol: )

hopefully it's not a much bigger job like the head gasket.

[Quantum TD]

Let us know what year and model vehcile you have, as well as engine. We'll be able to help you out better.

If you have boil over, then check the coolant return line.

If you just run hot, be sure to flush the rad and clean the fins with acid (at your local rad shop).

If you've got both, and greasy coolant  (and no oil cooler), then you may have a blown HG.

But, it's not the end of the world. If you have an NA, then repair will be cheaper, and you can surely do it yourself (same for turbo, but more work involved). A good head repair will solve your woes, and add HP and fuel economy to boot. Figure about $500 for a head job if you do it yourself.

But lets hear more about the car before we jump to conclusions.

[The Mad Hatter]

Sorry for the lack of info, i'm super frustrated at this point.  Its a 1985 Golf 1.6L NA.  Its totally stock.

-It has A/C, but it doesn't work.
-It does not have an oil cooler.
-I do not know if i have boil over.
-The gauge is running on the hot side, the light comes on when it feels like it.
-The coolant i drained out was greasy looking.  The thermoswitch had sludge on it, and the bottom of the overflow tank had the same sludge, i washed it out.
-I have seen no smoke, except yesterday when i was revving it slightly in my driveway, there  was a puff with each rev.  Didn't look white though, more blue gray, but it was at dusk, i'll check again when i get home.
-The cluster has worked fine since i put it in, until the alternator went.  I do have the original cluster as well, i could swap that back in to test the cluster i suppose.
-I was not losing coolant at any time.  It was full even when it was overheating.  It has a new water pump, and i tested the fan, that works too.  I had an oil leak, but it was at the pressure sensor, external to the engine.
This problem didn't happen until i broke the alternator belt a couple of weeks ago.  The car sat for a week while i tried to figure it out.  I put a new alternator and belt on it.  The next day i drove it and it ran hot.  Is there another sensor for the gauge that i'm missing?  I replaced the one in the overflow tank, and the thermoswitch for the fan.   I'm taking it in to get the rad. flushed this weekend.  I hope that covers the info needed.  I can add more!  Just ask away!  Thanks!

[The Mad Hatter]

Well, i've replace the thermswitch, the coolant level sensor, the thermostat, the lower radiator hose, and had the radiator flushed.  The gauge sits right on top of or just to the hot side of the light now.  It seems to be ok.  The fan comes on if it gets any higher, and it comes back down to right on the light.  So i guess its ok.  I drove it around today.  Didn't overheat.

[burn_your_money]

Here's hoping

[madmedix]

You're pretty much describing what my 90 TD does without the warning light. Somebody farts in front of this car and the temp guage starts climbing like I'm chugging up a 600' grade.
You're not alone on the parts replacement schedule, here's what I've done to her to solve this riddle:
Replaced the t-stat (verified opening at 185)
Replaced the oil cooler
Replaced the overflow tank (yuk)
Flushed the coolant system. 5 times. (Best result? Baking soda. Ran that through on the 5th attempt and the crap that cleaned out looked like it was the first attempt).
Fan system service

...and it still does the dance. Funny though; this car did not do that for the first year I had her.  Only started after a really, really cold winter snap. Even plugged in and with synthetic oil, she didn't like starting for about a week straight. Now, the guage swings. For now, I live with it. As long as I'm not on the side of the road with her looking like she's smoking a cuban cigar, I'm ok.

Andy

[The Mad Hatter]

madmedix, i would look at the coolant level sensor in the overflow tank.  mine was covered with sludge.  I replaced it (its cheap).  Now, i'm not sure what fixed my issue, but all the stuff i changed and the rad flush has gotten her running consistant now at least.

BTW

Somebody farts in front of this car and the temp guage starts climbing like I'm chugging up a 600' grade.

I almost fell outta my chair.  :lol:

[jtanguay]

madmedix, i would look at the coolant level sensor in the overflow tank.  mine was covered with sludge.  I replaced it (its cheap).  Now, i'm not sure what fixed my issue, but all the stuff i changed and the rad flush has gotten her running consistant now at least.

BTW

Somebody farts in front of this car and the temp guage starts climbing like I'm chugging up a 600' grade.

I almost fell outta my chair.  :lol:

thats a pretty sensitive car  :lol:

[shegel]

my car did the exact same thing. i was gearing to change the radiator, but when i pulled the old one there seemed to be a mice nest between the radiator and the  ac condensor. cleaned it out. and now she sits right before the middle mark(only because i havent put the 180 t-stat back in(still 160) but it seems to be fine) i average about 44 mpg nomatter how i drive

[The Mad Hatter]

The saga continues...

After 2.5 days of driving it to and from work (about 300 miles so far), the temp gauge is still acting crazy.  The light comes on at random, sometimes flashes, sometimes stays solid, and doesn't correspond at all to the actual needle.  The needle has spent most of its time in the normal range, but more and more frequently this week, its just starts climbing for no reason.  I drive on flat roads, 65mph, and the gauge doesn't stay consistant.  

SO, i'm pulling out this cluster (i bought it used since its a tach cluster) and putting back in the original clock cluster to see if its the gague.  My question now, is there some sort of control module for the coolant gague in the dash, or is it just the under hood sensors and the gauge?  Also, can i just grab a gasser cluster and take it apart to get the coolant gauge out of it and put it in my tach cluster?  Diesels are RARE out here in east NC (my dad has the only other one i've ever seen), so finding used parts is, well, difficult.   Thanks for the help guys!

BTW, my ultimate goal now is to put in a 2 gague pod on the A-pillar, and install an EGT and Water temp gauge.  I just don't trust the VW instruments after all this!  But i gotta do something to fix it for the time being.

[The Mad Hatter]

CORRECTION.  The light does have an effect on the gauge.  When the light starts going bonkers, that's when the gauge starts climbing.  I paid more attention on the way home today.  BUT, about halfway home, it just settled slightly below the light, and acted normal.  WTF?!?!!  This car hates me!  Lol.  I can only guess that it's the gauge, or some sending unit or something.  I'll switch in the other cluster later this week, as i'm just too busy today.

[burn_your_money]

I don't know much about the internals of the clusters but I do remember someone (Vince I think) saying there was a voltage regulator in the cluster for the gauges and whatnot to regulate it at 10V. Assuming my memory is working properly that would definitly be something to look into

[Giles@PerformanceDiesel]

hi
hope this helps, i have just been thru this too and it wasn't
anything but a bad sensor.

i have tried 4 so far and they all read different on my gauge

anywhere from 115C to 90, i put in a manual temp and
verified that it was not running at 100-110 deg C

Giles