N/A TD42 55mm PWR Radiator - Running Hot

[Wethapeople]

I'm at a loss as to what's going on. I'll set the scene.

I've driven down from Darwin to Melbourne with the original 20+year radiator recently rodded and repainted. No issues with running hot sits at 1/4 on the temp gauge at 110kmph. Happy days.

I decided to give the old girl a birthday present while down in Melbourne and purchase a 55mm PWR Radiator. Wow this thing looks nice, far nicer than the old radiator.

IMG_5895.JPG

So it's installed, has new radiator hoses, Nissan Genuine Thermostat, checked to make sure there's no stray current going through it and all is well.

It's on my drive back up to Darwin where shit goes downhill. As soon as I’m in 25-40*C heat the car starts sitting on 1/2 when sitting on 110. I end up getting back to Darwin pretty hot and bothered and I didn't run the A/C on the trip up because it kept cutting in and out with the temperature.

I've arrived back in the NT, since being back I’ve had installed a new Genuine Viscous Hub Fan and Genuine Fan Blades and later this week the Redarc temp gauge gets plumbed in so I can get an accurate temp reading. Since having the fan done I’ve been on a few drives and the car is still running hotter than normal/ it did with the stock radiator.

Why I’m concerned is I’ve spent good money on a radiator that doesn't appear to be cooling as well as the standard unit. I can get a genuine radiator for 750 delivered, this PWR radiator costs the price of two and appears to be not as good. Additionally living in Darwin it's always around 30*C so there’s no such thing as a 'cool' day, often I end up driving to Kununurra (40*C) and so on for fishing trips as well.

Other things to mention;

- 8*C approx.. difference from Radiator inlet - outlet (checked using laser temp gun)
- 40k Old Genuine water pump
- Replaced temp sensor for gauge
- Condenser at the front has been inspected and is in good condition.
- New Fuel Filters
- New Belts w/ new Bearings

Nothing has changed on the car except the radiator, I've not put bigger lights on the front or anything it's all the same, It has all shrouds and so on and is sealed nicely.

I have contacted PWR, they've said to send it down to them for an inspection ($280 in shipping costs) and they will have a look at it, but before I do that I just want to know does anyone else have any other suggestions? I also realise that people will say it sitting at 95*C is fine and so on but when it's never done it before I personally don't think that is 'fine'. As we all know too much heat kills motors.

Cheers.

[PeeBee]

If you have the original radiator, count the number of 'fins per inch' (FPI)and see if they are the same. This is a trap on radiators in that a factory radiator might have say 12 FPI oe even 14FPI and the aftermarket shiny unit has 10FPI. The difference is a considerable difference in transfer area. Its the fins that allow the heat transfer process to take place. I get 12-13 deg C top to bottom on my copper radiator.

I got caught with this some years ago and the radiator was not shedding the heat and was over-pressurising the aircon system to the point the compressor was locking up - sounds like what you are getting. I fixed it by getting the core replaced with the same number as factory fitted.

The fins are the thin metal bits between the core.

[GQtdauto]

Not a fan of aluminium radiators at all .

[Wethapeople]

PeeBee,

I haven't got the original radiator anymore but i'll have a look into it. What kind do you have now?

PWR claim to have sold 280 something radiators to people all over the place who have said they're amazing... I'm pretty annoyed it's not quite performing like that for me.

Cheers

[Wethapeople]

I'm fairly certain the standard radiators are Aluminium with plastic end tanks. I thought they were pretty good to last 20 years.

Any suggestions on replacement radiator GQtdauto?

[mudski]

High coolant temps at high speed is due to air flow. The PWR rad is a very good radiator, alloy rads dissipate heat faster than copper, but are not as strong as a copper rad. It is very important that both front sides and top and bottom of the rad are sealed against the support panel. Get some foam from Clark Rubber and make up some seals. If there is no seals, at high speed the fast moving air simply hits the radiator air and goes around the radiator instead of through the cooling fins.
I would guess the fins on the PWR are tighter, or closer together than the rad you removed, which makes air flow a bit more restrictive. This should not matter but it may. I would seal up the rad against the support panel and see how you go. The A/c condenser also has seals on it too. Which are more than likely no longer there.

I am currently going through the never ending nightmare on my own TD42 but I think I may have fixed it.

Good luck.

[Wethapeople]

Cheers mudski, I will give that a go as well.

[PeeBee]

PeeBee,

I haven't got the original radiator anymore but i'll have a look into it. What kind do you have now?

PWR claim to have sold 280 something radiators to people all over the place who have said they're amazing... I'm pretty annoyed it's not quite performing like that for me.

Cheers

OK, if the fns are as close as @mudski states then this is a good sign. You will have good heat transfer even at low speeds as the surface area is large. It seems others have done the hard yards here regards getting to root cause, so I would suggest you take note of what the likes of mudski suggest for sure. Sealing up around the radiator has a big effect.
My radiator is a custom copper core and part of a Chev diesel v8 conversion. It still gets hot and I am also on the quest to control temps. I am experimenting with both the mechanical and electric fans right now to try and fix my low speed temp issues, but this is different to your issue.
PWR is a good brand so I would think 'something else' has possibly changed as well. Are you sure you burped the radiator to get rid of all the air, front end highest point? I know stupid question, is coolant the same - different brand, mix, concentration? Are you carrying more weight? Is there an issue with your Radiator CAP - @AB had this recently on his barge. - sorry stallion.

[Tip12345]

try this find a steep patch like up the side of a drain nose up the car then remove radiator cap . its a little bit of air somewhere trying to escape !!!! my Rodeo used to get one under the temperature sender .... just loosen it let out the tiny bit of air all was well. it will be something silly and a bugger to find ..