Pressure Build Up!!!

[Tom Power]

Hello... My first post here. I have a 93 2.4lt. The head has being changed about 2000 miles ago. Iv being paranoid ever since so I always check the fluid level. But recently I herd bubbling coming from the expantion tank when I switched the car off. So after about 20 miles to get home I havnt drove it since.
Symptons are just coolent coming from the cooling system into the expansion tank, (about a pint or so)
I ran it for about half an hour without the rad cap on, No bubbles!!! (PHEW)
No white smoke either.

Could it be my Rad cap needs changing, or even airlocked???

Cheers.
Tom...

[Dixie.t]

I had that, a new rad cap and parking it on a up hill over night with the rad cap off got rid of the airlock for me, i hope this helps

[wishbone]

When the engine gets hot coolant is meant to go into the expansion tank. Then as it cools down it's meant to suck it back in. A pint sounds excessive though ?

Put a genuine rad cap on anyway as they fit much better than the pattern ones.

Check all hoses for leaks - they can suck air into the system too...

Rob.

[Tom Power]

I know coolant is supposed to flow into the expansion tank when hot. But it's bot gettin sucked back out when it cools. No cracks on the pipes, I'll try a new rad cap and leaving it on a hill for the night. Hope it's nothing serious, she's after giving me hell already...

[Brussels john]

I have got the same

Hi

I have had exactly the same problem. Cleaned out the RAD and new Cap, new Thermostat. Still it heats up. Found out whilst on Holiday that my Viscous fan was not getting up to speed, in fact it was staying at the same speed all the time. Checked some threads on here, and found out this is not an unusual problem and that I need to refill the fan with Silicon oil. Have this planned for next weekend. Worth a look just incase your fan is not cooling the rad properly.

Brussels John

[Tom Power]

Thanks for that John. Ill give it a go. Any idea what weight silicone oil I should use? and how much to put in?

[Brussels john]

Oil weight.

Hi

The oil that is recomended is 3000cps. You can get RC Car Shock Absorber Damper 3000 CPS Silicone Oil, or Tornado Stoßdämpfer Silicon-Oil Visk 3000 - 50ml - NEU you can get this cheap off of e-bay or your Toyota dealer in the Uk can probably get you the orriginal stuff. Its not expensive and you need around 50ml to fill the fan.

There are some good threads on the sight on how to this.

Good luck.
John

[Tom Power]

Thanks again, I picked up 500 from the local rc shop. Would that do??

[Brussels john]

3000cps

Tornado Stoßdämpfer Silicon-Oil Visk 3000 - 50ml - NEU
or RC Car Shock Absorber Damper 3000 CPS Silicone Oil

Both can be got on ebay. Or you could ask your toyota dealer. The tubes from toyota are 18ml and cost around 5 Euro's out here, so it was cheaper for me to order the Tornado from Germany.

There are lots of threads on here on how to refill the viscous fan. Unfornately its not just a quick top up job.

http://www.hiluxsurf.co.uk/forums/sh...2580#post62580

The one above is worth a look at.

good luck
John

[Brussels john]

Hi Tom

I know that Toyota recomend 3000cps I have heard people say 3000 or 5000. But not 500.

John

[dieselboy]

I know coolant is supposed to flow into the expansion tank when hot. But it's bot gettin sucked back out when it cools. No cracks on the pipes, I'll try a new rad cap and leaving it on a hill for the night. Hope it's nothing serious, she's after giving me hell already...

this happened to me and my 2.4. the problem was the rad cap was too weak and secondly my over flow was blocked. what this meant was for some strange reason it would let some water into the expansion tank, but when it tried to suck it back in it couldnt. the vacuum caused the top hose to squish in all the way.
new rad cap and a blow through the hose cleared the crap and solved my problem.

[Tom Power]

Got the Silicon oil 3000cps. Where in the fan do i put it, have the coupling seperated and old oil cleaned out, do I just throw it in there or should i put it somewhere specific? Cheers...

[andycook]

i poured it in the side nearest engine,

[Brussels john]

Hi,

When you have the two sides open, you will see that one side is ressesed the other side pertrudes. Just fill the ressesed side with the oil. it will level out if you leave it for a few minutes.
When putting it back together, make sure that you replace the rubber seal carfully. I used a knife blade to push mine in after loosely putting in a few of the bolts.

I cleaned my fan out with spirit and soaked it overnight to get all the crap out. before doing mine I could hardly spin it. Now it spins freely and blows a gale through the rad.

Good luck
John

Sorry to be late getting back to you. Just lost my job, so been spending all my time on the car.

[dieselboy]

may be i'm mistaken, but i have been taught that the fan blades should not spin freely. as the engine gets warmer, the fan is supposed to get "stiffer" so that it spins with the engine.

it made sense to me, that if the fan spins freely, that the engine would be turning and not spinning the fan up to speed... ?