Running hot. Can not figure out why. 2J MKIII... 240* on the highway

Poodles

I play with fire
Jul 22, 2006
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How is a clutch fan loud? Maybe when it's locking up and doing it's job. Not like you're going to be hearing it over anything else on the car (namely exhaust)
 

IJ.

Grumpy Old Man
Mar 30, 2005
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mkiiichip;1685950 said:
I also had no undertray, and no temp problems.

You never answered my question about the temp probe. The cheap probes cycle the fans, while over heating, (while lowering coolant temps minimally (only lowering probe temps)).

While your at these coolant temps the fan should never shut off.

So is it a cheap probe?

IJ, I understand your logic, but the undertray is there for efficiency purposes, any setup should be able to keep the temps in check without it. (especially when the vehicle is undrivable because of overheating issues.)

I am still willing to bet that the OP has a probe in the rad to control coolant temps.

As I said in a previous post there's something else wrong, Undertray missing is +5c so if the cooling system is marginal for any reason that is often enough to tip it over the edge...

Even just the row of bolts missing under the Rad support is enough to see a 3c rise in engine temps.
(there are another 4>6 blockers that are installed on a stock car that are probably missing from the front of most Mk3's that all act to guide the Airflow through the Radiator and prevent it spilling off the sides/bottom)

I've tested all of this as know it to be correct, as for everyone posting that the Tray makes no difference on their car if you're going by the stock temp gauge stop posting now as it has a huge dead zone in the middle where it can be 10c difference and the gauge doesn't register, I logged all of this via the MoTeC.

By the time the stock Gauge says "Hot/ouch" it's too late...
 

gurley0916

Gurley=Last Name not girl
Mar 10, 2008
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eman2289;1685952 said:
Will a clutch fan fit on a 2J in an mkiii?? It doesnt seem like id have enough clearance...

---------- Post added at 12:10 AM ---------- Previous post was at 12:01 AM ----------

Im not sure of what type of probe it is, but the fans do not shut off until the car cools down to around 180 i believe.


EDIT: I see that it does fit. That may be my best option. Can I possibly use better e-fans? I dont wanna have to listen to the loud clutch fan...

It was a tight fit and you have to shim it sometimes away from the water neck, I did that and had the fan go through the radiator when I bumped a curb. To fix this problem I shortened the water neck so that the fan would not have to be shimmed on the water pump. Best idea in my opinion. Gave me lots of room on both sides I highly recommend doing that if you can!!!. Plus I never hear my fan over my wastegate :)
 

JPsToyota

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Sep 17, 2008
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jdmfreak;1685972 said:
y not just hard wire your fan to keep it on then go for a test drive???.... that could narrow your search down for you a bit

That's what I was going to suggest for the first thing. Start with the most obvious and easiest to test and go from there. Wire the fans always on, make sure they are pulling through the radiator, and go for a test drive.

Then we can rule out the fans.


There are some threads about the nasty "rusty" coolant and overheating with 2Js on supraforums.com , not trying to chase you away from here but I had the same problem with my 1J and that's the only place I could find anything, even though there wasn't even much there.

I am going through the whole motor with new seals, new headgasket, new waterpump, new radiator and a hardcore flush to get rid of my "rusty crap" coolant problem and fix my mystery overheating issues.
 
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eman2289

Noob..but not incompetent
Feb 23, 2007
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IJ, I understand and agree. But there has to be a greater problem than just the undertray missing.

I'm going to wire my fans to constant power and see what happens, if that fixes it, then maybe I just need to rewire and re-adjust the control box.

The water that was coming out when I flushed the system was clear. This was after I used Prestone flush and then drained and flushed with hot water.

Id like to keep the e-fans, but if they can't keep the car cool, then ill have to put a clutch fan on it. But then that opens up new headaches with making it work in the mkiii
 

IBoughtASupra

New Member
Mar 10, 2009
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If you want to use electric fans, use the Ford Contour fans and get rid of the control box. Get a 180 temperature switch and wire it to the relay. It will send a ground to switch on the relay.

I was going to do this on my 7M but it made no sense seeing how much better the fan clutch is.
 

te72

Classifieds Moderator
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Mar 26, 2006
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Poodles;1685967 said:
How is a clutch fan loud? Maybe when it's locking up and doing it's job. Not like you're going to be hearing it over anything else on the car (namely exhaust)
This. If you have an aftermarket exhaust, you're probably not going to hear the fan much. I only notice mine if I get out of the car.

IJ.;1685981 said:
By the time the stock Gauge says "Hot/ouch" it's too late...

I believe the "ok/middle" zone on the stock gauge is something like 175° F to 235°-ish. Not exactly what I'd call accurate.

As for my setup, the e-fans I'm using are sufficient in keeping temps reasonable where I live, where the ambient temps rarely exceed 90°F, but when I go down to Vegas or Phoenix, I kinda have to hope that I don't have to idle for too long, as things get warm. Stock twins, Mishimoto fan/shroud setup, and I see anywhere from ~190-210 on the highway.

I would suggest you get a fan that can flow a good deal more CFM, and for the time being, either don't drive it (if you can) or hardwire the fans to a switch, just turn and leave it on when your car gets above 150 or so.
 

eman2289

Noob..but not incompetent
Feb 23, 2007
618
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Jersey
The thermostat is quite new. Dont remember exactly when i changed it, but im going to change it again...

Toyota Pink, sorry. The 50/50 pre-diluted stuff.

Im going to swap the thermostat once i get a chance and go from there. After I do the thermostat, ill hardwire the fans.

Thanks for all the help guys.
 

IJ.

Grumpy Old Man
Mar 30, 2005
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eman2289;1686185 said:
The thermostat is quite new. Dont remember exactly when i changed it, but im going to change it again...

Toyota Pink, sorry. The 50/50 pre-diluted stuff.

Im going to swap the thermostat once i get a chance and go from there. After I do the thermostat, ill hardwire the fans.

Thanks for all the help guys.

Why not just test the T Stat instead of replacing?

Pot of water on the stove heat it up and watch it ;)
(if you want to get real techie drop a thermometer in with it)
 

eman2289

Noob..but not incompetent
Feb 23, 2007
618
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Jersey
IJ hahaha, yes, i could do that.... if i had a thermometer... ill rummage through my drawers and see what i come up with.