how much do you let your engine/turbos cool down before you turn the engine off?

 

what is your prefered method off cooling down? idling (if so how long do you leave it)? taking it easy for last part of journey not using boost? any other methods?

I just drive a bit more casually for the last 2 mins of the drive then let my turbo timer sort the rest :D

 

If i hadnt got a turbo timer, id let it tick over for about 1 min and thats with the casual drive back.

Leaving a car ticking over will only cause the temperature to rise as there is less airflow over the radiator. Its not really temperature you want to worry about. The idea of taking it easy is to keep the oil flowing through the turbo. The turbo is primarily cooled by the oil so by keeping the oil flowing and not working the turbos hard, they cool down :) Nothing really to do with water temp :)

thats what i was hoping to hear!

do all TT's heat up on idle without the additional air flow when moving because I have been quite worried I had a problem. I was sitting in traffic for a long time on Friday and my temperature went up to +100C due to sitting on idle and the temperature creeping up about 0.1C every second. What do people do when that happens? I know the sub fan is meant to kick in a 105C but is that adequate to stop the temperature going even higher?

I have a switch to turn the fan on and eventually I am going to tie it in with the turbo timer. Check your viscous fan coupling as I would think this should be working long before 100 degrees. Comments re the viscous fan anyone?

shouldnt spin freely if you turn it by hand.... if it does its fooked the coupling that is

yeah the viscous fan is working and doesnt spin freely when pushed and does change speed with higher revs.

 

Does everyone experience rises temperature during idle?

 

NZ have you done the mod DAB1 has done in the follow thread..... http://www.300zx.co.uk/forums/showthread.php?t=72665&highlight=fan+switch ? If so, does the fans original purpose, ie to kick in when the temperature exceeds 105C, still happen or is it now disabled?

Aux fan is there to give additional help when its needed. It does do its job and will kick in when needed, lowering the temperature. It will then turn off and the temperature will rise again... repeating cycle.

 

You may find in cooler weather that the aux fan never kicks in as there is enough cooling for the engine on tickover.

 

Just about ALL cars will exhibit this behaviour - apart from air cooled obviously :D

thats what i was hoping to hear!

do all TT's heat up on idle without the additional air flow when moving because I have been quite worried I had a problem. I was sitting in traffic for a long time on Friday and my temperature went up to +100C due to sitting on idle and the temperature creeping up about 0.1C every second. What do people do when that happens? I know the sub fan is meant to kick in a 105C but is that adequate to stop the temperature going even higher?

 

Have you got a proper Temp Gauge? A good one so you really know what temp your actually reaching.

 

What kind of rad do you have if its a standard rad does it need flushing. If your car is a UK auto and rad is crudded up you really will see temps climb as the gearbox oil cooler flows through the rad.

 

Take under tray off and drop bottom hose of and blast the rad through with hose pipe. Then put it back on and you can buy a descaler. Fenox central heating system flush workes just as well. Bang it in and run car up to temp and let it run for about 20 mins. Then let it out and fill with water and run again let it out and same again so as to get rid of any flush. Top up with Glycol and way to go.

 

If it is crudded up you'll see a major difference.

Hi TPV01

 

I didn't follow DAB1's mod but it does look interesting. Looking at his circuit in http://www.davidboyce.co.uk/300zx/f7.pdf it looks as if the original control of the fan from the ECU isn't lost as long as the green and blue fan cables remain connected to the original locations.

 

The additional timer he mentions to remove heatsoak at the end of the run is what I was going to do in the long term too (i.e. turbo timer run down plus a few minutes)

 

I have removed my viscous fan and put in a huge mother f$%^er electric fan which I believe came from some sort of Volvo. The air flow is very impressive and the radiator is cooled to the point where the heat given off by it just about disappears. The only problem I have now is that it draws such a big current it dims my headlights so I have some wiring and relays to replace :)

 

With the fan I am using, the mods completed to date (including the air con condensor removal to increase air flow) and the future mods I am contemplating, I don't have a lot of cooling issues even with a stock radiator (which is in good nick).

 

Another I am looking into (when my Ostrich gets here http://www.moates.net/product_info.php?cPath=50&products_id=57) is to lower the temperature (and perhaps increase the speed) at which the electric fan kicks in.

Is it really that easy to do the Rad?

 

Just unclip one of the pipes going into the rad, and flush it out....

 

How much Antifreeze needs to be put back in?

Is it really that easy to do the Rad?

 

Just unclip one of the pipes going into the rad, and flush it out....

 

How much Antifreeze needs to be put back in?

 

Yep it really is that simple.

 

Usually a 4.5 ltr will more than do. Get the long life Glycol (Pink sometimes Yellow) and it should be 70% Glycol to 30% water. when I descaled my car and flushed it through 3 times I just put pure glycol in as there was water in the block after flushing.

 

It sure cured my over heating problems during the summer months.

I will try the descaling flush next time i get the chance. From doing a google i think the stuff markzx is talking about is called Fernox (http://www.plumbworld.co.uk/93-187) and can be bought from screwfix direct. Can any comercial descaler be used, like the stuff you can put in your kettle or is then a product specially made for car rads?

 

Hopefully the descale and a good flush out (the empty of the radiator and expansion tank i did last weekend flushed out some horrible browny-blue water with bits of leaves floating around in it!!!) and top up with some Water Wetter will hopefully sort out my temp rise during idle problem. I do have an after market SPA water temp gauge which measures from the top hose from the rad i think. Dont take much notice of stock gauge as it is either always at the bottom when started up or in the middle the rest of the time. My car is UK manual so shouldnt have the problems with the gearbox oil cooler flow.

 

NZ i am interested in the mods you have done too so keep us updated. What does the Ostrich do? Also, the thing i was wondering about with the original function of the sub fan being retained is the path of the current from two sources (relay and ECU) causing shorting out of the fan, relay or even ECU. Would diodes need to be installed to prevent current flowing the wrong way?

I will try the descaling flush next time i get the chance. From doing a google i think the stuff markzx is talking about is called Fernox (http://www.plumbworld.co.uk/93-187)

 

Thats the baby

 

Used it loads of times on older cars. You really see a temp difference. Works brill in ya central heating system as well.

wowser, i have never seen my temp above 90 degrees, even when giving it some round castle coombe, when sat in traffic it doesnt go up at all.

I bet if you had a good aftermarket gauge you'd be amazed at the Temp fluctuations of both Oil and water.

I do have a good aftermarket gauge, and datascan, rock solid temp on my water, never looked at the oil one

I do have a good aftermarket gauge, and datascan, rock solid temp on my water, never looked at the oil one

 

Na your right the water don't move much, but the oil does I've see 110 degrees when giving it pain up the mountains.

NZ i am interested in the mods you have done too so keep us updated. What does the Ostrich do? Also, the thing i was wondering about with the original function of the sub fan being retained is the path of the current from two sources (relay and ECU) causing shorting out of the fan, relay or even ECU. Would diodes need to be installed to prevent current flowing the wrong way?

 

Hi TPV01

 

The Ostrich is a real time chip emulator. It replaces the Eprom in the ECU to allow programming to be changed as you drive (well the passenger can do it ;) ).

 

Re the extra relay and the ECU supplying power to the fan - no problem. If you have to sources of power at the same potential, there is no fault current flow. They may share the load of the fan between the sources, but this is a good thing at it lowers the loading of each circuit.

 

My new fan only has one winding, hence one speed so some functionality is lost but the airflow certainly makes up for it.