Electric Fan Controller Temp. question

[Pretaco]

Not too hot, the gas engines run much hotter then a diesel.
Also at 15psi pressure in the cooling system, it can go up to 230° before boiling, each pound of pressure adds 1 degree to the boiling point. That is also tested at the thermostat housing on the outlet side of the engine, where the coolant is the hottest.

[SilenceboneSupra]

allright then thanks for all the replies i will chek them out see what suits best for the engine

[mkiiisupra]

Any updates on this? although i think id want my two perma-cool fans to cut on a little earlier than 203 ?



Probably set that high since the temps are taken at the hottest part of engine. Would seem that running the fans based on temps of coolant in the radiator would be more efficient idk

[SilenceboneSupra]

i got it set at 195 F.....

[batmmannn]

I have 2 1987 NA Supras and they both have a stock electric fan unless you were talking more than one electric fan on a car. My fan is not working I think I need a new fan relay. My car is getting hot and losing fluid out of the overflow tank, I already replaced the thermostat and radiator cap. I can drive it an hour and it will lose 2 cups of fluid. No sign of a blown head gasket. It was over 80 degrees today.

What do you guys think my problem might be? My clutch fan is good unless I have a blockage in the radiator or simply I need my fan to be running .

Also I don't have my compressor belt on but that would not effect my fan running, possibly the heat sensor for the fan? I hooked my fan up directly and it ran just fine so I am thinking it is the relay since my car sat for 7 years.

How do you test the fan relay and sensor? Thanks

[Green7mgte]

those two fans on the side of your radaitor are for the AC condenser. pretty sure there was a post discussing this about a week ago.


http://www.toyota-supra.info/forums/...-fans-for.html

[batmmannn]

Mine is an 88 NA Supra, my electric fan is for the radiator. I don't have a turbo. It is for the engine when AC or outside ambient temps cause the motor to run hot. It can't be for the condenser cause it is bolted right up against the radiator, no fan cooling could even reach the condenser. I only have one large electric fan. I did read that thread though earlier. Thanks for the reply.

Here is some info I found:

1.3: Cooling System

All early model MA-70 & 71 Supras have is a small rubber plug {part number#90339 16001} installed on the engine coolant transfer pipe {where the hoses to your heater core come from next to the top, right, rear corner of the 7M GE and GTE engine block}. Because this small plug is located in a very hot area of the engine bay {between the exhaust manifold and firewall} it has a tendency to dry out and crack on older Supras. If this plug comes off all the engine coolant will be expelled onto the exhaust manifold making a super big mess and steam show, as well as damaging your engine due to overheating. This plug is very inexpensive {five bucks} and must be replaced when you have this seasons coolant change. "Never work on coolant system when engine is hot".

It is important to change and flush engine coolant every year; always use the best quality product you can buy. The thermostat should also be changed if there is any instability in the temperature gauge, the gauge should always run at the same position while cruising down the road, there should be no fluctuations in the gauge reading such as a steady climb and fall of the needle over a two-minute period. I recommend using genuine Toyota thermostats as many of the after market brands do not work correctly for some unknown reason. It is very important to use a thermostat. Without one the radiator will not cool the coolant down before it lets the coolant into the engine again, this will cause the engine to over heat.

Toyota radiator hoses seem to last forever but be sure to inspect them for cuts and cracks, also fan belts and the clutch fan should be inspected. I am experimenting with a new product called Polypropylene Glycol coolant which is non-corrosive and safe to the engine and the environment. This coolant offers better heat transfer capabilities than traditional Glycol.

Your fan is used to cool your Supra on the highway as well as in slow traffic around town. Depending on engine load and conditions the fan will engage at some times to cool the radiator. In the front of the clutch fan there is a coil loaded thermostatic bimetal coil that will engage the fan based on air temperature passing by the fan blade. On many older Supras after many miles the seals around the temp coil will start to seep the viscous oil from the fan clutch assay, after the loss of the oil over time the clutch fan goes on holidays and your motor gets the added benefit of about 4 hp and no fresh air intake. One of the symptoms of this problem is a floating temperature gage. See PMTN for MA-60.

Depending on your body code there are one or more electric fans already installed on you're supra. If you want, you can wire up a simple relay logic box and switch that will allow you to fire the fans at will when the ignition key is in the on position, When you do this make sure you do not confuse any other factory systems, will the fans come on whenever needed. This is a cool upgrade for turbo cars I have my AC fan setup to run for 3 minutes after engine shut down if desired, the MA67's small AC fan pushes away a wondrous amount of heat from the engine compartment.

Another super upgrade for MA-60 is to replace the 5M-GE clutch and fan with the 7M-GTE unit. Some trimming of the fan shroud is needed but your supra will run as cool as a cucumber. The 7M GTE fan and clutch move a sizable amount of extra air through the radiator.

1.4: Intercooler System {Turbo Only}

The Intercooler used in the Supra Turbo is of the air to air type, this means it uses the air the car drives through to cool down the hot air that was sucked in through your engines air filter before being pressurized by the turbocharger on the way to your engine. The stock Intercooler on the MA-71 Supra Turbo has proven to be mostly trouble free, the only problems with it have been in three areas relating to maintenance:

Because the Intercooler sits in front of the air conditioning condenser that sits in front of the radiator, the Intercooler tends to be a rock & bug stopper. A small firm bug screen installed in front of your Intercooler is all that is needed to save it from most rocks. 2 If the Intercooler is plugged with bugs you may want to remove it to have it professionally cleaned by a reputable radiator shop, I would recommend you ask to wait at the shop while they do the cleaning job for you. This is a very expensive and high quality and useful part that could be used on many other performance cars! Cleaning the Intercooler will return its efficiency to original condition of a brand new unit. If the shop has the equipment I would also recommend that you have the Intercooler pressure tested to be sure nothing has punched a small hole into it. 3. The other item that should be serviced relating to the Intercooler is the plumbing pipes and hoses that run through the Supras body. There are a number of 75mm hose clamps that need to be checked for tightness and condition, with the combination of the rubber hoses aging and the many miles of bouncing down the road, many of the piping connections will be loose allowing inlet charge air to escape to the atmosphere under boost, and alternately allow dirt and grime to be suck in while under vacuum conditions. The 7M-GTE engines EFI computer cannot realize or compensate for this air leakage therefore it will incorrectly calculate Air Fuel mixtures, causing drive ability and idling problems. This job is easy to do by removing the under carriage splash guard and other plastic protectors, then following the air piping from the air filter to the engine then out to the Intercooler and back to the engine again. Be careful not to over tighten the clamps because they will strip out or break. It is normal to see a residual amount of engine oil in the Intercooler plumbing lines; this oil comes from the PVC system {Positive Crankcase Ventilation}. Replace all cracked or broken parts with Toyota Genuine Parts {they have been designed to work correctly under all conditions.}

[batmmannn]

Well I have swapped out my fan relay assembly and what I think might have been wrong with my car was that the clip on the overflow bottle that attaches to the radiator was loose and sucking air. My car now draws in the fluid from the radiator overflow bottle and then expels it to the same amount during cool down. I still have no fan but I am not sure my car has gotten to the point temperature of turning it on.

I hooked up my AC belt just in case but the AC compressor is seized it ate the belt right off.

I am doing this bypass wiring on my fan and installing a switch in the cockpit.

Here is a great link on how that is done.

http://www.clickdesign.co.uk/supradu..._override.html

[Green7mgte]

i want to know how the guy had it so his fans stayed on an extra 3 minutes after the car was off..

[batmmannn]

Let me guess,..... Trained Squirrels???