I don't belive [sic.] you.

Except that the fan, with the stock undertray and shrouding, will pull air through the oil cooler, so your long, simplistic "explanation" is not valid.

The oil system is pressurized, to at least 30 psi at idle, 17 psi more than the operating pressure of the cooling system.

Not only is your basic principal [sic.] wrong, but it is stupid to base such on "its a good explanation, it must be right". You haven't tested it, so your opinion is not valid.

Speaking of fuking [sp.] dumb, you misspelled "you're". Instead of commenting on whether or not another person should be allowed to own a car based on their relative intelligence levels, perhaps you should evaluate yuourself.

 

There isn't much on the passenger side for oiling since it is likely, with an 1986 RX-7, that your car is not turbocharged.

There are two commonly failing oil lines on the driver's side. They run to the side of the radiator, and are braided stainless steel. They see oil directly from the oil pump, and is regulated to at least 30 psi by the oil pressure regulator. I would cheack these lines for plitting.

It is easiest to jack up the car and remove the undertray via the 13 10mm bolts to examine the lines completely.

 

*holds up Scathcart's hand* TKO. PV=nRT. n, R and V are held constnad so P has to be dirrectly related to T. Pressure is double that of normal air conditions, temperature tollerance needs to double. (sorry those of you that hated chemistry)

As far as how the oil sprayed out, if a line on the drivers side came off or bursted could it have sprayed towards the passenger side and done the oil patern like you saw?

 

a oil injector line may have broke. they are on the passenger side but i dont think they have enough pressure to spray to the back window since they are powered by vacuum, and theres not much vacuum at idle. there is also the omp, but i vote for oil cooler lines and them things aint cheap

David

 

thank you very much for that scathcart if this was true about our cars the rx7 would not have made it as big as it did. yeah car can't idle for 30 or 45 min if this was true I would own a honda. Obviously they are not going to design a car that can't stand the pressure of idleing. I know its not the best thing for your car but its not going to kill it either.

 

pv=nrt is an ideal gas law and not necessarily related to oil spurting from a broken line.

 

Listen schmuck. The oil system is NOT pressurized. A pressurized system would need bleeding, and not have air in the system, and would require pressurized caps I.E. the cooling system. The oil pump flows volume of oil, but is not a pressurized system, thus also why you can remove the oil cap with a warm engine and have no ill consenquenses, but if you did that with the cooling system coolant would go everywhere.

You live in Canada let me guess it is less than 30 degrees there right now? I have no doubt the ambient temperature outside right now where you live is good enough to keep the oil cooler cool, and the you oil temps at a safe level.

Are you inferring that it was just random that this huge oil leak sprung? And in no way was related to letting the car sit for 30-45 mins? Doubtful, very doubtful that this was a random unrelated incident.

 

back to the original post...try checking your oil pump...if the pump failed your pressure might be too much for the lines thus causing the temp to go up. if everything is in working order the car should be able to idle for a long time.

 

Also, he said he was working on the cooling system, and obviously checking for leaks and such. My guess is that if you are checking for leaks on you 7 that you have removed at least the stock undertray to do so.

 

I'll be polite as possible here. Think about what you've said for a second.

Debris at the bottom of the tank? Ok, where would the fuel pump take the fuel from in the gas tank? The top?

Well, that would mean that once you've burned off the top layer of gas, you get no more.

Ok, so maybe it pulls from the middle? Sure, then once you hit half a tank, you have no more fuel to the engine.

The fuel sender pulls from the bottom of the tank, all the time, no questions asked. So there's no more "debris and crap" down there than anywhere else in your gas tank. Running it low does no harm. The only harm is if you have it low enough such that the sender can't always get fuel. (while you're turning or braking hard or something like that)

 

Car Maintenance Q & A
Chicago Sun Times.


Q. How long should you warm up an engine before winter driving?
A. An engine shouldn't idle for more than 15 to 30 seconds in any season, especially if it's fuel-injected. One exception: The engine of a vehicle about to pull a heavy load such as a trailer should be allowed to idle for five minutes or so to allow the oil to become adequately warm



-Robert

 

then why do i have an oil pressure gauge ?

 

well im going to crawl under there today and check it out. i did have all the plastics off, but i did have a garage vent fan blowing into the oil cooler, and radiator ofr most of the time. i put that on it about 5 minutes into this test. i will let you guys know what i find.

 

That's bad news

Thats good news I hope everything is okay. I really doubt you did any irreverable damage, probably juest a line of some sort that busted.

Good luck, keep us posted.



-Robert

 

What I am taking about is not that there is not oil pressure. I am saying it is not a closed presureized system like a cooling system:






"The radiator cap actually increases the boiling point of your coolant by about 45 F (25 C). How does this simple cap do this? The same way a pressure cooker increases the boiling temperature of water. The cap is actually a pressure release valve, and on cars it is usually set to 15 psi. The boiling point of water increases when the water is placed under pressure.

When the fluid in the cooling system heats up, it expands, causing the pressure to build up. The cap is the only place where this pressure can escape, so the setting of the spring on the cap determines the maximum pressure in the cooling system. When the pressure reaches 15 psi, the pressure pushes the valve open, allowing coolant to escape from the cooling system. This coolant flows through the overflow tube into the bottom of the overflow tank. This arrangement keeps air out of the system. When the radiator cools back down, a vacuum is created in the cooling system that pulls open another spring loaded valve, sucking water back in from the bottom of the overflow tank to replace the water that was expelled."



The oiling system does not work like this.

 

[edit] Original post edited for being too nasty.


The oil system most definitely IS pressurized. At 80 psi, no less. My upper oil cooler line blew this past fall, so I've had a pretty good, recent lesson on the topic.

The oil system DOES vent. That's what the purge valve is for, and why people have to put a catch can under the hood if they remove that purge valve.

Like den said, what do we have oil pressure gauges for? Decoration?

 

read the above post.

 

yeah, oil isn't pressurized. There's oil pressure, yes, but that's the pressure in which the oil flows. It's not the atmospheric pressure, which you seem to be mistaking it for.

 

Thank You. somone is using their head for somthing besides a hat rack.

 

rpec you clearly do not know what your talking about. i do not know the oil system like the back of my hand but can say for sure that the oil system is pressurized. i am almost sure that anywhere after the oil pump the oil is pressurized to a certain level depending on the rpm of the engine. the sump is just a resevoir for the oil untill it is needed. the coolant resevoir does the same job as the oil sump and the oil pressure control valve does the same job as the radiator cap i think.

 

oil isn't under pressure? so what is oil pressure and how come we have a gauge for it? u never specified atmospheric pressure from mechanical pressure...hence the misunderstandings. oil will not boil from extended idling...there isn't enough friction internally to create the heat to boil it. whatabout cars without oil coolers (most don't have them) that operate at high RPM constantly (think a 1.6 liter VTEC on a track)...the car is in the 6000-8000rpm range all day without boiling oil. If anything extended idle is worse for your cooling system than your oiling system but thats why we have a fan and therrmostats. your car bursted a line someplace...oil cooler lines are common to burst after age, check them and get yourself some braided lines for peace of mind.

 

A closed atmospheric presurised system cannot be based on RPM. RPm would be the basis of a volume of presure. Thus back to why coolant will blow all over when pulling the cap off a warm car, and oil will not, when pulling the oil filler cap, or dipstick.

Infact is the oil system was presurized it would blow the dip stick right out of the block.


The oil system is measured in PSI by volume only, based on the flow of the oil pump.



Would coolant boil over without a water pump? Yes. very quickly infact.


Would oil blow out of a oil line without an oil pump? No. It would drip, based on gravity alone.


-Robert

 

this has now been anwsered at least 3 times.

 

It is the ideal gas law but I believe it holds true with liquids as well. If you have enough pressure on a gas in theory it will become liquid? If you have water in a 250 degree container it will be a gas after a continueous period, but if you were to pressurize the system you raise it's boiling point and make it a liquid again.

 

also this is only reflecting the boiling point, not the actual temperature of oil. If you're addressing the boiling point, it's where the oil is turning to gas which means you have the gas being pressurized by the liquid molecules around it at the same pressure thus raising the boiling temperature.