Cooling Issues

[tdan]

Howdy Y'all

I'm not sure if I am in the right section or not, but I will ask my question to see if anyone out there can help me out with the issue I am having. I currently own a '95 R33 GTS-T and as the title state, I am having cooling troubles. After having driven my car in peak hour traffic the other morning, I noticed the temperature of my Autometer gauge reach about 110 C. After seeing this, I looked at the factory gauge and it appeared to be normal operating temp. Kinda confused the hell out of me!

Once I arrived at my destination, I turned the engine off and heard some sort of gurgling sound. I lifted up the bonnet of my car and saw all the water from the radiator being pumped into the overflow bottle. I watched it slowly fill up and sure enough, it did. Then to my surprise, the water began being sucked back into the radiator. That was what I found weird and confusing. I'm not sure if that is supposed to happen or not. I don't think so.

About a week ago, I gave the whole cooling system a flush and a clean with some cleaner bought from super cheap. Once that all went through, I ran clean water through the system and waited for it to run clear. Which it did. I also removed the thermostat, after being recommended to do so by a mechanic. Something about not needing them in areas like this. No snow in WA.

My main problem is that I don't know if my car is behaving normal, or if it has some major problems with the cooling system that need to be fixed before next summer. I am lost with what to do next as I don't want it to heat up that much that something goes bang and I'm up for a new engine, or worse a new car.

If anyone could help me out with advice, I would really appreciate it. And if you need more info, just ask and you will receive.

Thanks in advance.

Tony

[Sandeep]

I would put your thermostat back in for starters. Just because it doesn't snow in WA doesn't mean you should run with no thermostat, your mechanic should know better.

Was your car overheating before coolant change or has this only started after you changed the coolant/removed thermostat. Did you bleed the system properly? you may have air pockets in the engine.

I have heard people saying that with no thermostat, there is no restriction and the coolant flows much faster through the block/heads and radiator. This means there is less time for the coolant to absorb heat from the block/heads and less time for the coolant to cool down in the radiator. I don't know how true this is though, but I still think you should put a thermostat back in.

[ClutchBurndout-:(]

definatly put the thermostat back in, there in every car for a reason

[GTR-N1]

I would put your thermostat back in for starters. Just because it doesn't snow in WA doesn't mean you should run with no thermostat, your mechanic should know better.

Was your car overheating before coolant change or has this only started after you changed the coolant/removed thermostat. Did you bleed the system properly? you may have air pockets in the engine.

I have heard people saying that with no thermostat, there is no restriction and the coolant flows much faster through the block/heads and radiator. This means there is less time for the coolant to absorb heat from the block/heads and less time for the coolant to cool down in the radiator. I don't know how true this is though, but I still think you should put a thermostat back in.

Tick - Tick - Tick = All Correct ^^^

Stick that thermostat back!

Double check the Bleeder valve to see that all air is out of your system!

If the temp rises only whilst stopping at lights/peak hour traffic, you may have a suspect fan clutch. If this is so, the temp drops down again as you're moving at speed.

[tdan]

Thanks for the replies guys. Firstly, I did bleed the system properly and the bleed valve is on correctly. So, there should be no air pockets in the system at all. Secondly, my car was overheating before the flush, collant change and thermostat removal. Well, according to the Autometer gauge it was.

As I said in my original post, the water temp on the Autometer gauge reached 110C, but the factory gauge showed normal temp. I was also thinking that the probe for the Autometer gauge is faulty and it is now time for a new one.

One thing I will be doing for sure is putting the thermostat back in to the system. Once that is in place, I will check the whole system again and bleed it through thoroughly. Then I'll see how things go.

One question, what temperature rating would be the best to go for with regards to the thermostat?

Thank you all again for your help and assistance. I'll let you know how things go once I put things back where they belong.

Tony

[TokyoTaxi]

Tony, get a genuine thermostat to suit your car ( which opens at 76.5C ) which is only ~$50.

Considering the age of your car and assuming you don't have any leaks, I would suggest you drop the coolant again, pull the radiator out and check the condition of the cooling fins and core. You might find that your radiator just isn't up to the task any more because of it's age or because there's 18 years worth of bugs & leaves etc that have become trapped on the front of it.

If yours has lots of junk in / on it, blast it with the garden hose from the back side to the front to get all the junk out.

MAKE SURE YOU DO THE SAME TO THE A/C CONDENSOR AND FMIC ( if you have one ) AT THIS TIME.

That might be enough to get you out of trouble but if it's not looking real good, chuck it and upgrade to something with a core thickness that's better than factory ( 16mm ). IMO, 40-42mm core thickness is the best compromise between fitment and function. I fitted a 53mm Koyo to a mate's car not long ago and it was a pretty tight fit !

Hope that helps

[jnr_chin]

as simple as it may sound i recommend if you have not done it as yet is to get a new radiator cap.

the autometer gauge is a bit more sensitive than the factory gauge giving more immediate readings.

if your system is ok hoses, fan headgasket, water pump, the alternator belt that runs the pump etc. for the water to run in the overflow bottle the cap has to give way first.

[CARSICK]

...or in peak hour traffic (as OP says), it can be the fan clutch.

At the lights, the temp can shoot up from 82 to 110 within 3 min.

[r32J3003]

im facing same issues 2...

i had replaced the clutch fan, n still facing same issue... when stationary, my water temp goes up to 100...

oh by da way, im in malaysia, thus its extremely hot over here...

[meet07]

Im using slim fans on my rb25 which is in a 240sx. I flushed the system and had the same situation. Tomm im going to bleed the system like I did about a year ago. Jack the front up, fill with the temp sensore removed. When the fluid come out then plug back up. That worked the 1st time I did my coolant flush.

my autometer gauge reads 210 F at idle. When it goes above that like around 215 the idle jumps from 1000rpms to like 1600rpms??? whats up with that??

[mosquitocoils]

I have absolutely no idea whether it's related, but I read years ago in a toyota hiace van user manual that the most appropriate RPM for cooling is 1500-2000 RPM... Could be related Demetrus? Like an automatic system activating to help cool the engine down?

[meet07]

weird........is 210 normal temp of is that way to high??

[Wacky Dee]

210F = 99C = too high

My R34 GTT was running at 99C just the other day when ambient was 25C or so .. just putting it around town.

Flushed old coolant, put new coolant in, bled the system .... no change.

Put a new thermostat ... no change.

Put a new 40mm aluminium radiator + new fan clutch in ... BIG CHANGE. Now she's sweet running around at 85-86C which I've read is IDEAL for the R34 NEO. The thermostat on the NEO opens at 82 so it's meant to run a little bit hotter than your standard rb25det (R33).

Now the only thing I'm contemplating is whether to chuck in that bottle of Redline WatterWetter in there as well ... but from reading all the reviews, its inconclusive if this stuff actually cools better OR if it inhibits cooling and as such just keeps coolant temps down giving a false sense of cooling. Plus a couple of people reckoned it leaves some sort of SLIME in the cooling system as it breaks down...