Fingers

a few q's for the knowledgeable:

A) I've established that normal operating temps are 170-190 degF. What's the threshold where you see "THIS MAGIC TEMPERATURE" and pull over immediately?

B) What's the "MELTDOWN POINT" where everything is FUBARED?

I'm beginning to worry. On a really hot day (like 80-90degF ambient outside temperature), I see temps of 210 degF with the A/C on full blast, in the worst condition (idling). Bad/Normal?

Roy James

I think that would be about as hot as i would want it, but it could get a little hotter and be alright, i just wouldnt feel comfortable doing it though. The Max temperature is boiling, thats when the water mixture cant disapate anymore heat, so pretty much its fucked. But with the coolant in there it shouldnt start to boil until highertemperatures (not sure on exact temperatures).

Fingers

It has nothing to do with antifreeze preventing the water from boiling, it has to do with it being a sealed chamber. Try depressurizing coolant at that temperature and watch how fast it boils

Project84

I was told that you should be concerned about your coolant system if the gauge gets into the upper 1/3rd portion of the gauge. Most people on here also agree that OEM thermostats and pressure relief caps are necessary. Don't Use stant or some other brand.

Fingers

I DO have an oem thermostat only a few months old autometer gauge.

Project84

How's your water pump and radiator? Does your overflow have any fluid in it?

Fingers

Yeah it does. I did a really shitty flush at the begginning of the season, because i couldnt find the block drain plug. I know where it is, i just couldnt reach the goddamn thing.

But there is still some crud in the cooling system that i need to get rid of. thats my next order of business.

Project84

That might help. drain it all and get new coolant and see where you stand after that.

Fingers

Any advice as to how to reach that god forsaken plug?

88IntegraLS

I would be concerned with anything over 200. Considering how rotaries do not like heat and can't take a cooking at all, I would fab a Fiero or Tempo Efan for those situations when you are idling and the clutch driven fan can't rev on its own w/o the engine being revved. Most OEM fans are electric for the idling in traffic issue.

Project84

I dont' know. I just rebuilt my motor and I drained my radiator then pulled the motor and let it hang from the hoist and drained the block into a bucket. Have you looked from underneath the car? It looks like it would be a PITA to do it from the top. You car probably looks like mine since you said you have A/C, and you probably have P/S too. Try different tools and see what you can come up with.

tmiked

WRONG !!

50% Ethylene Glycol/Water boils at 227 degF.

At 8 PSI water boils at 233, the 50% mixture at 248 degF .

Mixture BP is 260 degF at 12 PSI.

The coolant raises the boining point as does pressure. Between the two modent systems can operate a temperatures over 235 degF. But remember your gage is not necessarily at the hottest spot. 210-220 worst case should be ok.

Fingers

Right but coolant does not prevent it from boiling.

Anyways, yeah i do have a black magic m150 fan, set at 180degF. Yes, it does work. As does the supplementary a/c fan.

All the shields are installed, and the rad is clear of any debris.

damn it!

Project84

the black magic fan is pulling air into the engine compartment and not trying to blow air out the front of the car right?

Fingers

Yes double/triple checked that

it was originally going the wrong way and i corrected that very quickly

Project84

I don't know dude, I can't think of anything else unless the water pump isn't working. I've seen some that had blades broken off the impeller wheel. Maybe it isn't pushing water fast enough.

Fingers

maybe... but the upper hose is pretty firm when the car is on... indicating that it's pumping fairly well.

Project84

I'm fresh out of ideas.

88IntegraLS

There was a thread on Efans where someone wrote a very convincing essay on choosing an OEM ("junkyard") fan over anything from a performance shop because pull much more air through. I have also read many times on this forum how people who have had aftermarket efans for a while dislike their cooling ability and find the stock setup to cool more effectively.

Did your car have this problem with the stock clutched fan?

RXSevenSymphonies

iTrader: (2)

wait how did you fix it to go the other way?

Fingers

And it's only on really hot days.

Guys, there's no doubt in my mind 100% that the coolant is currently contaminated. It's very obvious. It's not oil or anything like that, its like a slippery substance... looks sort of like liquid rust... but not a HUGE amount of it... just anywhere it can settle, there's slight sediments.

I'll try flushing the coolant VERY WELL this time, and hopefully that will take care of the issue. If not, expect to read about an RX7 that took a plunge into Lake Ontario in the near future :P

Fingers

To tell you the truth, my stock clutched fan was in great shape. I replaced it because I wanted more room to work with in the engine bay, and man is there a huge difference.

I didnt have the gauge in before i swapped fans, which i guess would have been wise now that i think about it. But i don't want to go back to the stock clutch fan even though i still have all the parts.

There are hundreds of forum members that are running lower temps than stock on the m150 fan. I wanna be one of them

pengarufoo

well, here are some things to consider... how is your oil cooler? when was it last flushed and/or cleaned? Does it have any debris/oil/dirt junk on it? the oil does alot of the cooling so if that end isnt doing it's job you'll surely see higher temps in the coolant.

Have you considered making a better fan shroud? the black magic fan shroud doesnt encapsulate the entire radiator core, so when you're stopped in traffic idling and the fan is the only thing flowing air, you're not flowing air through the entire core... meaning the cooling system is not operating at it's best in this situation. On my black magic I've cut off the left and right sides and made it wider using fiberglass relocating the cut off sides to further out (the extremes of the radiator core)... you can do the same, fiberglass is pretty easy to use. Or you can find a OEM fan with a shroud that is a perfect fit for your radiator, and hope it has the CFM you need.

A proper shroud is a very important part of the electric fan conversion. Also make sure you have the belly pan installed and the gaskets sealing the radiator so the fan can only pull cooler outside air through and not air from the engine bay which is already heated.

bcty

Ive installed a temp gauge awhile back.. I have the OEM thermostat 195Deg.. It pretty much stays there and up to just below 210 while racing.. I wish I could find another temp thermo.. but no luck.. Victoria British shows a 170 and a 180 for the 86-91.. but no luck from the dealership that i goto.. so id say anywhere between 190-210 is ok..

Fingers

That's a good point, those gaskets are nonexistant. they fell apart. You're talking about the foam stuff right? Yeah those are long gone. Do i have to replace those?