Yeah, mine did the same thing, and I also cut off the hose and re-attached it with a new clamp. Then about a month later the car started losing coolant again, and the upper radiator hose was collapsing (I think the condition killed the thermostat). After driving for days trying to figure out where it was leaking, I finally slammed on the brakes and opened the hood just in time to see a really small spray of coolant coming from the upper heater hose. When I disassembled the oil filter pedestal I found that the o-rings were cracked. Once I replaced the o-rings, upper heater hose, and thermostat I never had a problem again. I'm not sure if you are having the same problem, but it sure sounds like it.

 

ill order some orings monday when i get to work. waiting for a new heater hose to come in now.

 

well of course i went and got a pressure tester and it doesnt fit the filler neck. damnit. should have never sold my 200.00 kit.

 

If the injectors are indeed leaking then your best bet would be to send them in to have them cleaned.
Witch Hunter does very good work www.witchhunter.com

For now though you can follow this method that a Mazda Master Technician told me to use: I have used it ever since, even after sending my injectors to Witch Hunter

.After you stop do not shut the car off
.Give the engine 5-10 seconds to stabilize
.Then take the RPM's to 1500-2000 and hold them there for 5-15 seconds depending on injector leakage (if you try 5s the first time and it still floods, increase this time)
.With the RPM's still at 1500-2000 shut the engine off, then immediately floor the accelerator pedal and hold it to the floor until the engine stops rotating

Keep at it, once you get the bugs out and start to drive this car you'll wonder why you didn't buy one eariler

 

well, the car cranked up on the first try this morning so it seems to be good on not flooding. no smoke or anything. but we are still going nuts over the coolant issues.

we compression tested the car today since i couldnt pressure test the cooling system and the readings were 90 on both the upper chambers. my buddy said that was pretty good for a rotary with 147,000 miles on it. and the plugs i just put in the other day looked pretty good. looked like they were only burning fuel.

just for the hell of it i put zipties on the over flow line to make sure the ends were sealing good. since there has been no coolant going in or out of it. well wouldnt you know after running for a few minutes the overflow was full(it was at half earlier,and you could tell no hot coolant was going in it). so i let it sit for a few hours while i mowed the yard. just pulled it back around front and checked the level, overflow was full but the radiator was low. wtf??

we just dont see it being the coolant seals with it not smoking, overheating, no bubbling, and not using an excessive amount of coolant, and no visual leaks. all that along with the compression readings has us stumped.

hope someone has some more suggestions.

 

I don't either.

I re-read all of your post and I did not find anything that said you have replaced the radiator pressure cap yet, that is what solved the problem of the overflow tank filling on my s4. I would start there if you haven't already.
As always, with the stock cooling system on a rotary, use Mazda OEM parts.
-Pat

 

i did replace the cap. but i used one that i sell at work. but i have ordered one from mazda. just waiting for it to come in. they dont have anything for my car there.

 

You really need to do a pressure check on the coolant system. I went through hell figuring out where mine were recently. Mine was mainly at the radiator cap and adapter on top tank of the rad. finally got pissed off because I couldn't get it to seal, and made an adapter out of aluminum and a bleader **** and eliminated it. Also found a couple of small leaks on the heater hoses to the TB. I believe the system is able to be pressurized to 10psi, if I remember right. By doing the pressure check, you'll be able to really look carefully at everything without the worry of the engine running or being too hot to work with.

 

If it has only been a week and you are ready to give up then sell it. There will be many more things to replace and troubleshoot ahead. Or bite the bullet and take it to a professional.

 

Bleed it the right way, jack up the front of the car or find a incline. Heater full blast radiator cap off, fill up radiator as necessary. Run for 20-30minutes.

If it is still doing it after you bled the system double check that small hose for the overflow tank, then try to get the system pressure tested for leaks. Even the slightest leak will trigger the buzzer due to air getting in.

 

ive bleed it like that a few times. we did find a small leak at the coolant temp sen yesterday so i pulled it out and re-sealed it. drove it again last night. everything was fine for the 3-4 mile drive to where we were going. but when it was time to go back home the buzzer came on again. but this time it was a little different. if i reved it up the buzzer would stop at 5k rpm. then when it got back down under 3k or so it would come back on. im still trying to find a pressure tester that will fit it.

 

Does the COOLANT light on the Warning display come on when the buzzer goes off?

 

yes, its the add coolant buzzer and light. but the new issue with it coing off when i rev it past 5k is a little weird to me.

 

well, just went out and checked it after letting it sit from last night.

the radiator was completley full and the overflow is at half. so if it was leaking it should have been low. so im getting ready to pull the egi fuse and turn it over with the cap off to see if it is pushing the fluid out and see if it is going into the chambers. but i dont think it is just by the way it has been running.

 

well, guess ill give a update.

went out yesterday and the level were both fine on the radiator and the overflow. pulled the level sensor jsut to make sure it was all good. my buddy took it for a drive and drove it a little harder then i do and said it started to over heat but when he turned the heater on it cooled back down. it filled the overflow and boiled over some. so we let it sit for a while to cool down and it looked like it sucked coolant bacj in when it cooled down.

still no buzzer yesterday or this morning. the only new development is the upper hose is very stiff when the car gets up to temp. how hard is that hose supposed to be? another weird thing to is the overflow smells like it migh have some fuel in it but the coolant in the radiator doesnt. so again we are stumped. the guy that drove it said it doesnt seem like its leaking in the motor going by the way his ran when it blew the coolant seals and by the numbers we got from the compression test.

really wish my mazda parts would get here so i could rule the cap and thermostat out. but if it ends up being the coolant seals im probally going to try the alumiseal stuff to give me some time till i figure out if i want to rebulid this one or get one my buddy fournd from a s4 with 40,000 miles on it for 400.00.

 

well now the car has really gone crazy. everything was fine for 2 days. no over heating, no smoke, no coolant light. so last night i pulled the coolant level sensor just to make sure it was still working and everything was cool. put it back in, burped all the air out and let it sit at idle for about 30 minutes or so. well we go to drive it to a friends and no more then a mile down the road it starts over heating.

so i pull over, let it cool down some and then crank it again. temp is fine for about 5 minutes and then starts going up again. so shut it down and bleed the pressure off the cap to add some coolant to get ti home. once i got the cap off i cranked it and it started shooting coolant out. so i shut it back down and added coolant. took about 1 gallon to get it full.

so im lost now. it doesnt seem like its going in the motor since it really has none of the blown coolant seal symptoms. but tonight im going to pull the thermostat out and install one i ordered from mazda. even though the one in it is "supposed" to be a oe one. and also a new mazda cap and see what happens.

already have a motor lined up. guy has a s4 motor with 40k on a rebuild for 400.00. so if i have to get it then so be it. im not going to sell this car. to much fun to drive. just want to get it to were im not working on it every damn day. my blazer is getting pissed at me. got a pile of parts for it just sitting but no time to install them.

but like i said before, any suggestions on whats going on would be great.

 

Don't know if this will help, but I had a disappearing coolant issue on my S4 that was related to the hose that ran from the top-back-passenger side of the block to the throttlebody... It's kinda a biatch to get at, but ti runs up to the thermovalve on the throttlebody. At the engine side, it started cracking a bit, which would then leak down to the intake manifold/exhaust manifold area and evaporate.. The big thing was that it wouldn't let the coolant system build the required pressure to work, and the car would overheat. Might be something to check!

 

ok, got home tonight and after replacing a wheel bearing on my blazer i decided to mess with the 7. i got a new mazda thermostat and cap. which i matched the thermostat i got from work with it and it was a mazda one from work. but i decided to change it anyways, ill just warranty the one from work. as soon as i took the upper hose off there was no coolant. but the radiator was full. so i got it all installed and let the car run with a lisle funnel to burop the air out. i ran ti for about 25 minutes, cut it off then ran it another 25 minutes. getting ready to go drive it to see how it does. but i did take some videos to show what its doing while im burping it. maybe someone will see something none of use here are seeing.


http://s179.photobucket.com/albums/w...t=CIMG0393.flv
http://s179.photobucket.com/albums/w...t=CIMG0394.flv


just got back from driving it. drove about 3-5 miles. kinda beat on it more then normal. no over heating and no buzzer. so we will see how it does.

 

Could it be that your car just has the dreaded O-ring problem and the motor needs rebuilt? I bought a 1986 Rx-7 in 1993 that had very similar problems - of course it had 171,000 miles - took it to an RX-7 expert and he said the motor would need rebuilt. This is after I personally replaced the thermostat, clutch fan, radiator, and some hoses. The car would run for a while then overheat. Sold the car in March 1994 and bought a Toyota Celica.

Fast forward to November 1995. Bought another red 86 rx-7 that needed a clutch. Lived in Florida at the time. Fiance cheated on me, got mad and drove to Miami (about 4 hours one way). As I hit the first Florida key, the "Add Coolant" light/buzzer went off. Yep, same problem. Corroded o-rings, needed a rebuild.

Fast forward to July 2009. Bought a 3rd red 86 Rx-7. Am I nuts or what?

 

well, thats the ting. ive had it checked out by people that have build these motors before and by someone that has had the coolant seals go out on them and they all the the motor is fine. so im just going to drive it and see. it blows it blows. already have a few options lined up in case. but i did notice last night that it sounded like there was air either coming out or getting sucked in at the cap. so im going to get another radiator i think and try it out. just sucks cause i just called the compenay we get it from and they have to make the damn thing. so it will be next week probally.

but it did fine this morning on the 13 mile drive to work.

 

Investigate a little more before throwing another part in that you might not need. Check the condition of where the caps seal, and look for cracks too.

 

i checked it out last night and its the neck of the radiator. it isnt the best aftermarket one. we usually have problems out of this brand, but when i got it there was no other choice. but i just talked to a place we just opened an account with and they can make me one for the same price and theres are supposed to be alot better qaulity. but i am going to check it out a little more cause i am tired of changing parts on this thing. think i have worked on it every day for 2 weeks straight. i need a night off. getting behind on my truck and ive got a customer dropping a car off to me tonight.

but like my buddy said, if it keeps screwing up we will just pull the motor and take it apart. if it just needs new seals it looks like i can get them from mazda for really cheap. just waiting for someone to answer my question in my other thread.

 

Why don't you just buy a Koyo or something similar if you need a new rad. I don't see the point in having one made that will most likely cost about the same. I also don't see how your "work" sells Mazda OEM thermostats. Post a pic of the one that was in there.

 

on the koyo without looking at how much one runs im pretty sur eill come out cheaper getting the one from my supplier. and my work sells beck arnley, and beck arnely buys from overstocked dealers and going out of business dealers and places like that and just reboxes the parts. so they are all oem. same stampings and everything. which one do you want a pic of? the one the car had when i got it, the one i got from mazda or the one from my work?

which the one that was in the car when i got it i dont beleive was the right one cause it was bigger then the mazda one and didnt look the same. so im sure it wasnt a mazda one.

 

Yeah, Mazda doesn't even sell a "Mazda brand" thermostat anymore, if they ever did. I bought one this spring from the Mazda dealer that came in a box marked "Mazda" with the same old familiar Mazda part number and the thermostat was made by MotoRad. FWIW, the old one put in by the previous owner was made by NTC.