krayon808

if its not one problem its another i have a 93 rx7 that thing is giving me so much stress, thinking of selling it but dont want to cause i love it. i guess i hate to love it. well the dam coolent wont stope coming out of the overflow tank, i changed the thermostat so it opens at 180 degrees and i put a alum. air separator tank but its still over heating and shooting out coolent... motor is still good. runs great.. please I NEED HELP

dubulup

I bet the coolant seals are still good.


*this was suppose to say "aren't still good"

my car did the same thing right before I came out of denial about a rebuild.

krayon808

how would i know if it is the coolant seals???

Montego

iTrader: (1)

are you sure your car is overheating? or are you just saying that because coolant is coming out of the overflow tank?

what are your water temps at? or did your stock gauge move to H?

krayon808

the stock gauge moved half way to h, but the aftermarket on that i put in was reading 220 is that bad if i is the coolant seals is there a site that would show me how to replace them???

Rotary4tw

iTrader: (3)

Overheating car is probably one of two things.

1) Coolant seals are compromised. This means that the link between the combustion and the coolant systems are connected, and when you drive the car, the higher temperature of the combustion is entering the coolant system (which is much lower pressure.) The result... the coolant system is "overpressurizing", pushing the coolant filler cap spring up, and allowing coolant to expand out to your overflow tank. (Coolant always expands when it's hot, as does water)

2) You have air in your system, or your coolant system is compromised and not able to build pressure. If it can't build pressure, it can't raise the boiling point of the coolant, which may cause it to boil, which would cause it to overheat. (You would probably have a leak from somewhere else though).

Way to test the problem cheaply...

Head to a local autozone, or car store. Somebody should have a "coolant pressure tester" that you can rest for free in your area.

What you do is hook it up to your car, with the car off, and pump pressure into the coolant system. Get it to about 12psi or so, and see if the system holds pressure. A normal system should hold pressure until you hit your spring rate on your coolant cap, it's a closed system.

If the system cannot hold pressure, the pressure from the coolant system is leaking into the housings, and you have direct evidence of a breach between the two systems. You will need a rebuild. (There are other options to put materials into your coolant system to try to patch up the hole without pulling the engine.)

You can also search on the subject "coolant rings" "o-rings" and find more detailed information.

I was in denial for a while too, and eventually had to get a new engine. Other things to look for... search for "Champaine Test" and also white smoke on startup. (White smoke from exhaust = coolant being burned that pushed itself into the engine housings after the car was shut off.)

Good luck, hopefully it's something as simple as your coolant system having a leak in it (apart from the o-rings).

-R4tw

Rotary4tw

iTrader: (3)

Even at 220f with zero pressure and a 50/50 mix of coolant water, that is not really enough to make the system boil. Odds are it happened once when you were not paying attention, and then the damage has been done.

If you are absolutely positive that never, not even once, your temps have been in the H or over 240, then you are probably okay for the o-rings. (Unless they are just really old and finally gave way) I remember when my gauge climbed up and buried on H for the first time... it happened very quickly and there is very little you can do to stop it... :/

-R4tw

NoviceRotaryTech.

You make it sound as if (if there was a leak) that leak is with the coolant seals which would need rebuilding, when it could be just a hose.

chinaman

If the system was not blead properly, this can happen

sephir0th

Open the other cap (on the engine side) and start the car, see if you get hundreds of little bubbles rising up, if you do, then its your water seals and time for a rebuild.

I had a similar problem with losing coolant out the overflow and It turned out to be the pressure cap... Replaced the cap and it fixed it up.

Good luck.
Hope it's not your water seals.

Rotary4tw

iTrader: (3)

If a hose (check clamps around radiator too) had a leak in it, wouldn't it leak coolant too?

I guess I meant for him to pressure test it, and if he didn't see coolant spewing out anywhere, but he was still losing pressure, it was likely the internal o-rings.

I remember some people saying that you can have a small enough leak in a hose to bleed off pressure, but not large enough for coolant leak out. Never really figured out if that was likely or not.

-R4tw

Montego

iTrader: (1)

half way to H huh... so are you saying that the gauge was righ down the middle or 3/4 up because 220 F = 104C & that's not overheating...

Basically more than likely overheat will toast your coolant seals. Replacing the coolant seals requires the engine removed and torn apart. In otherwords a rebuild. But don't fret I don't think you have a coolant seal failure. Unless your car is hard to start when cold, shakes really bad, and puffs out a lot of white smoke. Then after about a couple of mnutes the car is as nothing happened.

Replace your AST cap if that helps or actually stops it for a little while then your ast is not sealing properly. Replace the hose and tighten the hose that goes from the ast to the overflow tank. It may have a pin size hole it.

Montego

iTrader: (1)

I am not a fan of the champagne bubble test. Rust in the system can cause bubbles and foam. By definition my car had failed the test. Ran 20k more miles until it blew up cuz of that over boost issue on friday

yeah my AST wasn't sealing properly. When back to stock and never happened again.

Roto7FD

Sorry for jacking thread but say montego, what if car never overheated, basically new reman, but just hard to start (will crank), and puffs out white smoke and then goes away, no shaking though.

adam c

iTrader: (2)

Its possible that you have simply overfilled your cooling system & overflow tank, and that it is overflowing when the car gets hot.

Montego

iTrader: (1)

A new engine with bad coolant seals and has never overheated is not unheard of. Sometimes builders **** up and pinch a seal. Anyway coolant seal failure does not mean that the car was overheated at some point. But if the car gets overheated don't be surprised if they fail in the near future.

1) When one has a coolant seal failure it typically affects cold starts because there is coolant in the combustion chamber.

2) once you the car actually cranks over the coolant is still there and the car is essentially runing on one rotor. That's why it shakes like ****.

3) Immidiate after it cranks over that coolant in the chamber starts to evaporate. Hence the white smoke. It's usually quite a bit of white smoke too.

4) after it's all evaporated, hence no more coolant in the chamber. The car runs like a champ. Other than the car runs hotter than usual and may actually over heat.

5) as time goes on the problem naturally gets worse.

Now with you. If you notice all cars when cold puff white smoke. The smoke is due to the condesation in the exhaust. I would not worry unless the smoke is really excessive.

Your car not starting right up can be due to several things. From battery or alternator going out on you, to old spark plugs, wires. Coolant seal failure is not necessarily the only culprit.

if your car starts to shake and it's idleing say 800 RPMs then you got a problem.

ATLGT

iTrader: (1)

I am having the same problem, but without a coolant seal broken. No bubbles come up when I burb the system. So now I am placing back in the AST and replacing all my hoses. Also, a guy I work with said to check the seal around your throttle body to see if that is not broken. If it is, than turbo pressure can over pressurize the system and not allow for coolant to re-enter the system. As for me, I dont have the throttle body heated anymore.

psquare8

I had this issue a long time ago and the dealer had flipped the AST cap with the radiator cap on the engine. I was dropping a cup or more of antifreeze a day, they also replaced the bypass hose which was damaged as a result of the caps being in the wrong place.

czseven

while on this subject my car has overheated once but starts fine little white smoke only when cold out. but the temp does raise only when going up hill and over 70mph under that it is fine. WHAT THE HELL??????????

Roto7FD

Hmmm thanks montego, I think that gave me some piece of mind. I probably have fouled plugs or something.

Montego

iTrader: (1)

You may just have a problem with your coolant system/ blocked not working properly. I would check all of that first before thinking coolant seal failure.


no problem.

If a piston engine had a tendency to overheat, or have problem starting we would not jump to the conclusion oh it's a blown head gasket. We would check for possible culprits. Rotaries run on the same principle as the piston engine. The same components that would cause those problems in a piston engine would do the same for the rotary. So unless there is undisputable evidence that the coolant seals are going why not check other culprits first?

psquare8

Thermostat ever been replaced?

Trout2

iTrader: (5)

Just do the pressure test. Leave it on there for a while if pressure isn't lost immediately. This will give you a definitive answer.

I lived in denial for a few months back in 2001 before doing a pressure test. The stock temp guage is not reliable. Mine never went past the middle. In the end I tested the old and new thermostat and found the old would only open half way. Localized boiling killed the coolant seal as shown by hot spots in the motor. A simple $11 part killed a very healthy engine with 52,000 original miles (at least it lasted me 5 years and 41,000 miles).

An aftermarket temp guage or PFC with commander to monitor water temp is an absolute necessity with these cars.

Good luck, hopefully it's air in the system or a hose leaking.
Jack

Qball

my coolant buzzer goes started to go off a month ago. i fill it up and it goes off again about a week later.

Montego

iTrader: (1)

Qball change your AST cap see if that helps.