After i got back from work today I went inside for like an hour then came out to clean my oil cooler on my car, I popped the hood and it was still hot in there, so I got the rags wet and cleaned away anyways my finger touched the engine housing and it burnt me wtf? It has had an hour to coool down and is still hot enough to cause pain? Maybe im just a rotary noob but man is there anyway to keep the engine cooler?

I installed the electric fan and after i turn off the car it is still running and EVERYBODY comes up to me and says hey did you know your car is still running? It is kinda funny when they ask that cause we dont have it set to turn off when the car is off only when the engine reaches a certain temperature. Anyways does anyone know any thing to get to keep the car running cooler?

 

after i get home, i open the hood while its in the garage and it seems to cool down real quick.

 

Maybe im low on radiator fluid?

 

Maybe you shouldn't be sticking your fingers on a hot engine? I'll bet you are a teenager. Teenagers think everything should have happened like yesterday. When you turn off the car, it's not making heat anymore, so just forget about it, it will cool down in an hour or two (also, you might want to check the thermostat on that electric fan install, or go back to the stock fan, the way it's supposed to be). If the engine temp goes up while your driving around, give us another call.

Respectfully yours
Ray

 

The rotary exhaust gases are up to 250 degrees hotter than a piston engine. However the engine is adequately cooled to compensate for this. In particular the oil flow is a critical part of the cooling design.

Any rotary or piston engine takes time to cool down to external temperature after it is shut down. There is no advantage in speeding up the cooling period except possibly to turbos which need a timer while they spool down. Having a timer to an efan to the coolant radiator will have no measurable improvement to engine life and performance. In fact if you went to the extreme and ultra rapid cooling, there is a possibility of damage due to the different cooling characteristics of materials such as aluminium and steel.

If you have a cooling system problem and run too hot then there can be damage to the engine, but the damage will be done before it is turned off.

The moral is not to work on your engine until its not finger licking hot.

 

Damn, are you a hundred years old or what? I am only 21. I hate the snide comments on every question that 'oh you must be a teenager, you are dumb, and young, and I was never under thirty.' Grow the hell up. How about useful, intelligent information like he requested. Some thing like this...




Well, the exhaust is hotter than most piston engines, but the tempurature of the "block" or housings should be the same as an equivelent engine. 180-200 degrees aprox. You shouldn't worry about it unless on your guages it shows that you are running it hot. If it ever goes over one half on the temp guage, immediately shut off the engine and find the source of the problem.

 

Calvin, no offense, some of my best friends are teenagers, although as you suggest, I'm closer to 100. I think your suggestions for Erik are exactly right. Erik, forget my noise about electric fans and sticking your finger on a hot engine (you probably figured this one out already anyway), the important thing is to heed Calvin's advice:

"If it ever goes over one half on the temp guage, immediately shut off the engine and find the source of the problem"

Oh yeh, about rotary engines, they are definately very hot, that's why we love to drive them.

Ray

 

that is weird, i can touch any part of my engine while it is running besides the radiator and headers and they are only mildly hot. what kind of efan do you have on there. maybe it doesn't push enough air

 

Back when the first gen was fairly new, I took mine to a muffler shop to get an estimate. At that time, I already knew they ran hotter than a piston engine.

After the car was lifted in the bay, the muffler guy started to reach for the exhaust pipe to check for loose fittings and such.

As he reached up, I yelled, "hey, that gets real hot!"

He turned to me with an annoyed look on his face and said, "yea, I know kid, but I work with exhaust systems all the time, they aren't too hot for me."

Then he proceeded to grab the exhaust system with just a small rag in his hand.

You could hear him yelling and swearing for a long time as the exhaust piped burned his hand.

After he calmed down, I told him, it's a rotary engine, they run extremely hot.

 

thats good stuff right there. what kind of e-fan are you running? most ppl suggest around 2200-2500 cfm on a rx7. ive got mine on a thremostat like yours which keeps running after the car is shut down and ive gotten several comments about it.

 

I knew they ran hot, yes i am a teenager. Im just trying to learn more about my engine. I just figured after an hour it would be touchable. Here are some pictures of my E-fan setup.




On the temperature gauge the needle never even goes to the halfway mark or past it. So im guessing in runs cool. I just wanted to make sure I wasnt damaging my engine.

 

Cool Erik, take care of that puppy!

 

im getting my car painted right now and after i had it all taped up my friend had taped up my muffler which i didnt know so i drove into the booth and by the time i got to the booth which was mind you 20feet away i looked and the paper was burned away at the tips...lol

 

You can always pop a couple of vents on the hood to let out some of the heat

 

Is it hard to put those vents in the hood I noticed Kettlemans hood had vents in it and it looks pretty good. Thankyou Ray Green I really am trying to take care of this car and not abuse it. These things are rare and i wanna keep mine on the road!

 

You might also want to get a shroud of some sort, that way you are pulling air through the entire radiator and not just the center. Looks good though.

POST SOME MORE PICS!!!!

 

i will be doing this this month since i have a spare hood. i'll show you guys the results right after.

 

Please make a how to guide or show us with pics step by step so we can do the same without messing up our hoods.

 

actually... it will mess up the hood a bit.. lol

you will have get it repainted since welding marks will be left off and some bondo stuff as well.

i will also be removing some of the hood's under body pinnings to make it lighter. i don't mind since i will be using hood pins for the hood

 

what exactly are the exhaust temps of a rotary? from my experience i've heard more word-of-mouth people saying these engines run incredibly hot. however coolant temps seem fairly low. the exhaust temps out the back of my turbo flange on my supra can run upwards of 850c on 20psi of boost. this seems pretty high to me for a piston engine.

however, removing exhausts on Rx7s has to be the biggest pain in the *** ive ever encountered! not sure if its just the age difference or what, but christ, i've broken pretty much every bolt ive tried to remove on my SE

 

I do not think there is a problem. If the operating temperature is normal then your efan is the right size. An engine weighing say 300lbs operating at 200 degrees will take time to cool down.

As a teenager you will not remember pre-electric blanket days, but then a 3 pint hot water bottle placed in bed at 200 degrees was still warm to the touch six hours later.

 

Paradox an impact is your friend, best investment i've made in terms of a tool.

 

I have cut up, replaced, and staight piped 4 cars. I got one Nut to come off without breaking.

 

When your exhaust is hot enough to burn off engine paint designed for 1200*F then you know your exhaust is real hot. I have personal experience with this.

Surprisingly enough, I managed to remove my exhaust with only breaking 2 bolts.

 

got my exhaust off without ever breaking a bolt. If you go fast enough, a good oil leak will lubricate and rust proof the entire under carriage.