Cooling (again)

Heya! It's me again.

both of my last topics fixed the timing and the VDO gauges. Splendid!

Next problem arose rather quickly.

Was driving to the hospital in a city next to mine, via the highway. ran perfectly and on normal temperature.

However, when i came down from my 110 kmh to so traffic the thing overheated faster than i couldve imagined.

got it towed home and took a look, (everything was semi-&$%£&*)

I replace the water pump & water pumphousing & the thermal switch the fan kicks on perfectly at 87 Celcius now, every time. and keeps going after i shut the car off the overheating hasnt been fixed however. and there my question comes forth, i dont expect the radiator to be bad, since it has always cooled as it should and never did anything suspicous. my only ''suspects'' are the coolant-overflow-tank and its radiator cap (the tank itself has a molten smel?) & the oil cooler.

would anyone have an idea?

perhaps someone with a simmilar experience?

how do i check the oil cooler?

Thanks lads!

If you didn't replace the Radiator Thermostat.  That could be an issue.

If you didn't flush and black flush the coolant system and heater matrix, then you have missed a step.
If you didn't take the radiator shroud and fan off to inspect the radiator matrix, oppsy, never assume.
Especially of yours is the bottom side bolt and upper c-clip version

Expansion tanks go bad, as well as caps.
Also check all hoses for bad spots.

Another place of contention, is the lower heater hose connector, they are plastic and a time bomb.

Replace it with a Pex 5/8 pex or hose  coupler connection. They are made of aluminum or brass, and a couple of clamps.

Hose connector


pex


If you have plastic outlet flanges, then check them as they can leak at the bolt holes.

I suppose it was hot, it's not just the sender playing up, they're notorious for it.

In the old days when water pumps had longer snouts, and the pulleys were shorter, the weep hole was towards the bottom so you could see the thing drip if the seal was shot.  On Dubs the hole is at the top of the snout as it is mounted, and the Pulleys are such that the drip or spray drips on the inside of the pulley and shoots out every where.  When i had a pump leak, it took me a few days to see it even with a UV light.

I would flush and back-flush the system, and replace the thermostat.

You need to know for sure that the coolant is circulating properly.

I would go from there.

Thanks lads, i checked all things today that i havent yet,

i fully flushed back the system for a second time and nothing really improved. The thermostat was replaced and this did precisely nothing!

coolant is circulating as it should, thermostat opens perfectly at 85 Celcius (measurement might be a tad bit off)

pump housing and seal was thoroughly checked for the entire day, absolutely zero leakage of weapage whatshowever/

the pressure on all cilinders was checked and no leaks to or fro the cooling channels or the outside.

all hoses are good, nothing bad yett, im waiting on a new expainsion tank and cap.

*IF* and shall we hope not, the reservoir and cap doesnt fix it, im just ordering a new radiator.



 

If the thermostat is working and the coolant is circulating as it should, then there should be no overheating issues.

I assume it's definitely overheating and not just a fault with the temp gauge?

When up to temp - no leaks anywhere, Top hose is hot, bottom hose less hot? Fan kicks in?
Cabin Heater on hot with  fan blowing hot air? Hoses into matrix - one hot and one less hot?

Hmmmm - can only be the reservoir cap or head gasket….

cold engine.
remove res cap.
tie latex glove over the opening tight.

heater to full hot.
Start the engine and rev it to 3000 rpm 30 to 45 seconds.ant longer and it will inflate with the coolant getting hotter.
If the glove inflates and give you the finger mad hear gasket or water jacket oil cooler.

If you run your engine and the fan cycles 2 times, and your hoses are hard to squeeze bad head gasket.

Yeah, the coolant pipes get to the temp youd expect, no leaks anywhere.

Def not a sensor issue, car gets too hot. Engine dies and doesnt want to restart.

Reservoir & cap just came in. The storage location where i keep my golf is now closed till thursday, i will keel you updated

This sounds like a plan,

Defenitly hope its not the head gasket as i got that checked out a month ago and it was totally fine said the shop.

For question, you say tie a latex glove on the reservoir thread. If that fully inflates the head gasket is 👍🏻 if it doesnt fully inflate the head gasket is 👎🏻

Fan kicks in perfectly every single time and the hoses arent hard in any way. Feel brand new.


 

Marauder said

This sounds like a plan,

Defenitly hope its not the head gasket as i got that checked out a month ago and it was totally fine said the shop.

For question, you say tie a latex glove on the reservoir thread. If that fully inflates the head gasket is 👍🏻 if it doesnt fully inflate the head gasket is 👎🏻

Fan kicks in perfectly every single time and the hoses arent hard in any way. Feel brand new.


 

No, if the engine is cold.
Start the car and rev it to 3000 rpm for 30-45 seconds,
If the glove inflates during that time the head gasket is suspect.

The glove will inflate after 45-60 seconds any way.  but it it the first 35-45 seconds at 3K rpm.

water jacketed oil coolers also leak.

No, if the engine is cold.
Start the car and rev it to 3000 rpm for 30-45 seconds,
If the glove inflates during that time the head gasket is suspect.

The glove will inflate after 45-60 seconds any way.  but it it the first 35-45 seconds at 3K rpm.

water jacketed oil coolers also leak.


Aha!

If i got this correctly, its now time to pray for the glove not to inflate in the first 45 ish seconds, (at least not too much)

if this, and the new reservoir and cap situation doesnt fix it ill report back!

Thanks alot!