Overheating

[Johnny_k]

Hi guys, So im moving this thread over to here and pasting some of the recommendations and things have tried so far.

Problem. While having a tune done by Steve, all of a sudden my temps went sky high 108-112 and did not want to come down.

We had a look at the thermostat and it was fcked, so we removed it completely. We also found alot of gunk(thick sticky crap in the radiator and deposoted in the overflow bottle.

After giving the overflow bottle a rinse, the block and radiator a flush with a f/hydrant , I managed to get a tune done, however towards the end the temps were going high again like before.

By this time it was 3 30am and there was another car to be tuned. We were happy with our accomplishments and decided to finish up.

I dove her back to the bro/inlaws place 10 mins up the road. Got a couple hours sleep and decided to head home (Toowoomba 2.5hrs away).

Driving with any more then 10% throttle seemed to send the temp flying high. Turned on the air con... THat seemed to get the temp to go down for a while but then the temps went up again. Turned on the heater as per someones recommendation and that didn't apear to help much if at all.

So after chatting with Dom and noticing that the hose leading to the radiator could not be squeezed we thought that maybe all that sludgy crap was blocking some lines in the block and stopping or reducing flow, so I stopped and brought some nulon radiator flush and bam.... The temps stayed down just 1 notch under half way (prior to the tune half was normal and wouldn't budge from there unless going up the range.)

So i'll paste here some of the recommendations i got, but from hear, im going to get the radiator flushed and install new thermostat and then do another nulon radiator flush.

thanks to everyone that provided advice while i was trying to limp her home.. (wasnt fun at all)

 

[Johnny_k]

recommendations

not sure on that one man, I'd be inclined to pull a heater hose off and start the car for a second, should start pumping out. Plus, once you figure out the direction of flow, you can put a hose in the inlet side of the heater hoses to flush the system out with the car running.

The water pump still seemed to be working as you could see when the car was running without the thermostat, the water was circulating.

Worst scenario, turn heater onto max, no air con mode just hot fan, max, and either blow onto feet or window You should see the gauge drop down alot, this helps vent the hot water elsewhere

As far as i remember (And i am in no way an expert on cooling systems) bubbles in radiator can mean a couple of things: Water pump cavitation. Creating a froth from the water/coolant mix. Head gasket leak. Causing air to get pushed into the water jacket. With the head gasket leak, some say oil can get in to the water. So your water goes oily/milky.

How does it bubble? When you press the throttle or regardless while on idle.. Does your fan kick in at all?

 

[Johnny_k]

Just on the bubble, it was constantly bubbling. not just under revs but idle also. However i didnt bleed the system. Couldn't find a bleed valve. so i reckon that and extreme temps may have contributed.

 

[VOLK]

Glad you made it home man. Just wondering wtf would have caused this blockage in the first place?!!? Maybe chemiweld was used at one point to stop a coolant leak?
From what I read about bubbling cooling systems, it's potentially head gasket breached from cylinder to water jacket. I'm hoping this isn't the case for your Leggie though...

 

[mr barista]

My car is stable at around a notch under half at all times. Mind u i live in Port Douglas and our temps are always around 30 deg +.
However, we have a steep range that connects us to the tablelands, and even under the lightest run,the temp gauge flys up....
I replaced the pod filter that came on the car with the stock box, and upgraded the cooler,......still no difference!
I off to check the thermostat!

 

[Johnny_k]

Yeah i hope it was something else apart from a head gasket. and yeah check out that thermostat... God i hope u dont have an auto... the thermostat's a BITCH to get out due to the pipe off the front turbo and the bloody auto filter

 

[fieldy107]

if the fire hydrant helped it for a while, Im guessing it unblocked your lines just enough to get a tune done. I would flush it a few times over and make sure you get that shit out.

 

[TME_Steve]

Yep just blocked I reckon, it should be clean, not full of crap. Pull the hose off that is full of stuff and clean it out, replace it if need be. Then flush it, flush it again, and again and again. then repeat this process a few times.

Glen, yours may be a bit blocked too by the sounds of things, mine just never gets hot (unless it's on a dyno) I remember BradC had problems on a track and this was fixed by directing the air through the radiator but you guys aren't talking about driving that hard so....

 

[naughtika]

My question to Johnny_k..

1. How was the fire hydrant used? Which way was the nozzle pointed to? Top hose or bottom hose?

Top hose is return line.. And the bottom is the entry to the engine..

2. How hard was it turned on? I know that fire hydrants can give quite a it of pressure..

Only if you were closer i'd help flush the system and diagnose the issue..

Could also be possible that your coolant temp sensor is stuffed, specially if sludges were found in the system..

At this stage replace the thermostat as per usual, replace your radiator cap and add coolant.. then go from there..

 

[Johnny_k]

ok so i finally got time to tend to this today and well. Lets answer Christians questions first.
1. top hose
2. not that hard as it was held there and sealed by hand.

=======now==
Last few weeks I have been driving the car without a thermostat, having to wait forever to get any heat into her. Today i installed the thermostat and flushed the system once.

Then added another flushing agent and drove it for about an hour on the highway stayed nicely about half way until having to stop for 5 minutes with aircon running while i ran into the shop..

Only at that point did the temp rise at all.. and it rose to 3/4.

Started driving and within 2 minutes, back down to half..

Got to my destination, let it cool and flushed again. refilled with water and coolant and started to drive home and there it sat at about 3/4 the whole time, when under load it would rise and force me to stop and cool down.

Over 120 odd k's with minor hills i had to stop 3 times.

Wtf lol. Seriously gunna send it to the scrap metal yard soon.

 

[Abusive]

Sorry to hear you are still having issues man. I hope it all works out soon.

 

[Johnny_k]

Thanks mate. Hey did u go out to that grassy near Patrick's estate?

 

[Abusive]

Can't remember, probably got sorted out by the rurals, they only send us to grassys if there are houses under threat.

 

[naughtika]

I think your temp sensor is not working or that resistor pack thats sitting on your radiator fans..

how fast were you driving? so that the temp would not rise? above 60kph? to me, your new thermostat is doing its job by staying open while driving.. but once you stop and there's no air passing through the radiator, its not getting cooled down..

do you know if your radiator fans do turn on?

 

[Johnny_k]

Around 80 90 kph maintained around 3/4 temp and pretty sure fans work fine. It was really when I make the engine work a bit. So acceleration or uphil usual stuff. However when she got almost to red. If I nailed it for a bit . The temp instantly started to drop Back to the 3/4 mark and then would rise again in response to the work

 

[naughtika]

yeah, 80/90kph.. will keep air flowing nicely..

test your temp sensor to see if its working..

 

[Johnny_k]

I love to ask the stupid questions.. where is it

 

[naughtika]

top hose.. engine side.. follow where it leads to.. first sensor with black connector you see.. is it.. take a photo first then show us.. just to confirm

 

[Johnny_k]

Will do. Have to wait till tomorrow but.

 

[Johnny_k]

Had a quick look this morning. Couldn't find it. The top hose, like the bottom, runs to the thermostat housing. What do I need to remove, if anything to locate it.