Ok heres the deal. Im currently flushing my radiator as some of you may have already guessed by the title of the thread. Ok heres the question. I took the hoses off and I put water in through the top and then blew in to push the water out through the bottom. I saw nothing too bas juss abit of rust n the like. Then I put the hoses back on filled it up and turned the car on for abit to get any water that might be in the water pump. Turned the car off and emptied the water out and then once again i put water in and blew out to make sure everything is out. What else should I do besides connect the hoses back up and put in the coolant and water? And should I put in 70/30 coolant/water or 50/50? Ok thats all please reply a.s.a.p.

 

Flush with some detergent in the water.
Rinse it out.
Fill with 50/50 green stuff.

You will probably need to top it up the next day as the remaining trapped air bleeds out.

 

What are you trying to do ?? just flush the system ? were any problems causing you to flush the system ?? remove the thermostat and stick the hose into the housing to flush the engine, with the lower hose removed from the radiator, to flush the radiator remove lower and upper hoses and stick the hose into one end.
If you want to really deep clean the system put everything back together except the thermostat and fill with purple power degreaser, run the engine up to temp and then let cool, when cool stick the hose into the thermostat housing, remove the upper hose from the radiator and flush until no foam or trace of degreaser
is present. re-install the thermostat, connect all hoses, 30/70 is fine but depends where you live ,,of coarse. run engine to temp, check for leaks and your good to go.

 

Most coolant manufacturers recommend no more than 60% antifreeze. Since you live in Florida, the freeze protection isn't a major issue.

1. Make sure the heater control (temp) is full hot.

2. I find it works best to pre-mix the coolant before I put it in. Fill the radiator until it won't take any more.
3. Start the engine and let it idle. Keep adding coolant as it draws down.
4. Fill the overflow bottle to the full hot line.

5. Once the coolant at the radiator neck is steaming, cap it and go for a drive. Make sure you have your jug of coolant along. The low coolant buzzer is bound to go off, make sure the over flow bottle is full, adding as necessary.

This should get the air bubbles out after it cools. I always carry the jug of coolant for a day or two after I flush the system.

 

You should invest in a prestone coolant flush system. It basically has a T that you put into a water hose (such as the lower heater hose right next to the lower radiator hose. It always you to run a hose to this point and flush out the entire system. Great investment for $5. Water has a higher cooling capacity than coolant so dont run too high a concentration of coolant. To bleed the air bubbles out of the coolant system after start the car with the rad cap off and the heater to full hot and on and let it idle for a while while jostling the radiator hoses to help the bubbles along. Only use distilled water BTW.

 

Ok heres what I did and heres what happened. Right after the initial post I had to go to work so I put the hoses back on and filled her up. When I got to work(10-15 minute drive) I noticed the car was beginning to heat up because I felt the hose and it was kind of full with pressure. So while I was working I let the car cool down and then I opened the OFT and it was empty, I filled it up again, half with coolant, half with water. Then I began to fill the radiator up once again. once it was completely full I turned the car on and let it idle for about 5-10 minutes. The Temp gauge(which I think is faulty by the way, only marks 1/2 when there is already steam coming out the OFT vac line.) only read 1/8 after sitting there for 10 minutes or so. So I kept working and when it was time to leave I checked the fluids again. put abit more water in and then i headed off...another 15 minutes. On the way to work I took it real easy but on the way back I gave it abit more gas, not all the way down, but abit and by the time I got home, the OFT was bubbling and steam was coming out thru the vac line. Im real real worried here guys....I dont know whats wrong.... I didnt try what Mark Perez said but I probably will tommorow after work. I guess I will just keep taking it real easy. Please any of you....I need help here....besides a clogged radiator what could also be the cause of this? My thermostat is less than 6 months old and is OEM, I bought it from either mazdaperformance or mazdatrix, cant remember exactly who but Im sure it was one of them. Do I need a new thermostat? Thanks to all of you who have posted and thanks ahead for any info someone might give me.

 

It sounds like you have a lot of air trapped in the system. You always want to keep the overflow bottle 1/2 full because as the system pushes bubbles through the hoses and lines, they wind up going into the overflow tank. When the engine cools, it pulls coolant back into the system from the tank.

Some notes from the other posts. The guy who said only distilled water was right on target! Water has the highest "q" factor - the amount of heat it can transfer- of any coolant. You can run straight distilled water in FL as long as the temp never drops below freezing. You NEED TO USE AN ANTI-CORROSION AGENT! Water-Wetter is one such product, I'm sure there are others.

If you have A/C that works, use coolant and distilled water. 50/50 is a good mix. The reason for this is that when the AC is on, the temp is modulated by mixing a little heated air from the heater core with the refrigerated air. Without coolant (Prestone/Peak/Sierra) you risk temps very close to freezing across the heater core.

PM me and I'll send you a write up and presentation I did for Midwest Rotary Rally last summer.

 

Okay, here's my 2 cents.

1. Did you unscrew that small plastic plug with a phillips head on it from the top of the radiator where the upper hose connects? You need to in order to let out as much air as possible.

2. sounds like you may have a faulty radiator cap by the symptoms you described. Have you checked it? It can still have a bad spring even if the seal looks good.

3. Did you go back and inspect each of the radiator hoses that you removed earlier to make sure they sealed well? If there was corrosion on the pipes or the inside of the hoses it will prevent them from providing an air tight seal when trying to reinstall them even if they were good before.

These are just a few things I have learned to check when having problems with some of the ones I've owned.

 

Thanks. I was actually thinking the same thing about the radiator cap. I will have to check that out tommorow. If I need a new one would an autozone one be ok or do I need an OEM one like with the thermostat?

 

well, i know alot of people like to work on their own cars but at work we have a flush machine that works the best that i have seen, what you do is start the car up till it hits operating temps then shut off, then we hook up a flushing machine that pushes all the coolant backward through the system removing more rust, grime and scale alot better than you would imagine. i mean i have seen some nastey **** come out of some peoples radiators. just my 2 cents

 

You should use only OEM radiator caps and OEM tstats. Other ones fail. They arent even that expensive. www.mazdatrix.com or www.mazdaformance.com

 

-=sighs=- I thought my car was fine....but I was wrong.....after I flushed it yesterday I let the car idle while the bubbles were coming out through the radiator cap hole thing while the radiator cap was off....once I noticed the water shifted as in the hot water came out of the engine and the cooler went in I turned the car off and waited 15 minutes then checked the level and added abit more. I didnt test drive it because I had to get up early to go to work and it was already 10pm.....so i went to sleep when I went to work(15 min drive) the car ran great, and same thing on the way home....well I was bored so I went with my friend to Taco Bell to get a bite to eat well TB is like 20 min away....on the way over there the car sadly enought started heating up and by the time we were at the parking lot...POOF...the OFT cap came off and smoke came out...I let the car sit for about 20 minutes to let it cool down then I emptied my coolant container in there, there was like 1/3 left in there. I drove the car back home slowly and ov the way home it heated up again.....Ok im real sad and pissed off....the thought I never had is slowly starting to creep up to me.....that maybe I should sell my FC....I dont want to but Im 17 yrs old and I go to school and work...I need a reliable car....all I get weekly is around 110$....I cnt really afford to park my car and save up money for 3-4 weeks and not have a ride to do anything....please help......

 

Anyone? Any help would greatly be apreciatted....Im going to probably reflush my radiator today and do what a couple of you said, flush out the engine internal when I take the thermostat off, take the screw sensor thing at the top of the radiator off to let the air out....hopefully this will work, ok and if the car keeps heating up then what could be the problem? What are some symptoms of the coolant seals going bad?

 

it's not the seals !! is the passanger floorboard wet ? if not. it's not the heater core. how old is the water pump? when you run the engine with the cap off does the water circulate(move) or does it just sit there ? when the thermostat opens the fluid should be moving. if not it's either bad water pump or a blockage and the part with the smallest water passage is the radiator. in my t2 i bought a 180 degree thermostat from autozone, works as well as oem, a stant radiator cap is as good as oem also. these radiators fail on a whim and all of a sudden. i replaced my thermostat, water pump, and the engine still got hot so the last thing is the ?........... radiator. i went to the junkyard and for $45.00 dollors picked up a used radiator. i picked the cleanest one i could find with no signs of leaks or cracks. got home and cleaned it up more ran clean water through it for a few minutes then installed it. connected all the hoses to the radiator, left the thermostat out and stuck the garden hose in the thermostat housing and fill the engine with water. when full dry off the thermostat housing for the gasket to seal better and used hi-temp silicone. installed the thermostat and the filler neck then topped off with water. run the engine to temp and add water as needed. the thermostat goes in spring side in first, you know that,right. no air pockets exist when filling the engine with the thermostat out first. i would say radiator.

 

Ok...thats good atleast my coolant seals didnt die.....ok could the radiator cap let air in, because I suspect that my cap is gone, so Imma buy a new one cause I suspect its kind of old. water pump might be kind of old because awhile back after I had put the engine in it heated up and the waterpump was bad so we replaced it with a waterpump from the engine we pulled from my car and it worked so far....could that be it? Both engines seem to have over 100k on them..Im going to check prices because I will probably end up buying new radiator cap, new waterpump and new radiator..

 

do the radiator if the cap doesn't correct the problem

 

Ok thanks....oh yea is the Autozone waterpump trust worthy or should I buy an OEM one from mazdaformance or mazdatrix?

 

Damn man, I just realized that I forgot to post the number one most over looked problem in the world that causes the mystery overheating problem. I have had this happen to me at least 3 times in the past two years on different cars. I can't belive I forgot to ask if you have checked it out yet. I forget that the FC has a "mechanical cooling fan, I have an electric one and always forget nobody des the same as me. Anyway, the problem I am talking about is the clutch in the center of the fan not locking up. Have you checked that, do you still have a mechanical fan? Do you even know what I'm talking about??? LoL
The fan may look like its spinning because, well, it is. But is it actually locking up and spinning with force? Next time you take your car out and it starts to overheat pop your hood and turn off your motor, grab the edge of the fan, remember turn the motor off, and spin the fan by hand. Is it easy to spin? or does it feel like its locked to the hub on the front of the motor? If its all good it will have a lot of resistance when you try and spin it, remember that is good. If not there are a couple of good and chep ways to fix it.
1. upgrade to an electric fan such as the one from a pontiac fiero or ford taurus.
2. remove the fan from your car, get a hammer and proceed to smash the center of the hub in until it won't let the fan and hub spin freely. Basically smash all the internals together so the fan runs locked up constantly, at all RPM's and temps. When you do this it will also keep the motor much cooler than before.
Remember to always run your electric fan with a shroud, the plastic thing, it won't work, hardly at all, to draw air throught the radiator without it.
I can't belive no one else has thought of this. I can't believe I forgot about it. I think this maybe your problem if you can't find anything else.

Remember if all else fails, just through a couple of bottles of alumaseal or copper block in the cooling system, drive for about 20 minutes after already reaching operating temperature. Then park and let sit all night to cool down and seal everything up. Drive normally the next day for another 10-20 minutes after reaching operating temps. let it cool down then flush out your sytem and refill with the proper amount of coolant and water.

That's worst case scenario. It sounds like no matter what the mystery is that it can and will be a cheap fix. Good luck.

 

Time to post this------------------------
Sureshot’s Overheating – check list
1) Replace the thermostat. Make sure it fits. The spring loaded disc under the stat valve must close the bypass port, or guess what?
2) Replace the radiator cap. Low pressure = steam bubbles = spit out coolant.
3) Look for leaks. (same symptoms as #2) Some can be very hard to find. You may have to pressure test it. A common failure spot is the 3/8” coolant line that runs from the top of the rear housing (under the intake runners) to the throttle body, to the BAC, to the water pump. Another one is the heater hose under the oil filter.
4) The fan clutch will slowly start slipping as it ages. The fan should pull really hard up to about 4k when the motor is hot. It should maintain about 4k as the motor revs higher. Sometimes you can get more life from it by bending outward the bi-metal strip on the front of the fan clutch. The cut-in for the series 4 fan clutch is gradual – it pulls some even when cold. The series 5 fan clutch is more on/off.
Banzaitoyota’s checklist
1.Are the Oil Cooler fins clear of debris and clean?
2.Does the Oil Cooler thermostat function properly?
3.Are the Radiator Fins clean of debris?
4.Is the Stock Bottom shroud still in place?
5.If you have an electric fan, are you running a Dual Belt Pulley on the Alt?
6.Did you install a NEW Water Pump when you installed the engine?
7.Is the bottom hose collapsing under load?
8.Did you have the Radiator and Oil Cooler cleaned and Flushed when installing the rebuild ( AS required by MOST REPUTABLE REBUILDERS)?
9. Have you verified water temps with a real gauge instead of the sock POS?
10. What ratio Coolant to Water are you running?
11. Are you running a new STOCK MAZDA OEM thermostat?
12. Mazda Rad Caps?
13. Stock Fan Shroud installed ( For those of you running stock Mechanical Fan)
14. Electric Fan users: Do you have a Shroud installed at all. Most installations only draw air directly across ~60% of the available core surface area.
15. are the stock deflectors installed around the relays forward of the Radiator Core Support?
16. If 15 is a no: Do you have an plate mounted across the support to direct air-flow?
17. Install a spring in the lower rad hose to keep it from collapsing at high RPM

 

LOL - crude, by effective.
If you lock the fan clutch, you will have to keep revs below ~5K, or the belts will slip.

 

Wow thanks alot guys....I have to go to work, Im going to be driving my mom's volvo and sadly its a rainy day so I might not be able to get down and dirty with the RX, so hopefully by 6pm it stops raining enough to get some work done.....Alright guys again I thank you fully.

 

Hmm...no one ever answered me I think when I asked if I could use a radiator cap from Autozone.....or do I need a Mazda OEM one?

 

Well I personally have used the stuff from autozone and kragen for about the past 5 years with no problems. I have used the radiator caps and thermostats. You know all that Stant brand stuff, I have not bought anything from the dealer other than exhaust manifold and flange gaskets, they are better quality and cost less from the dealer.

 

I posted this in the 5th post.

 

Oh Im sorry, now i remember reading it...sorry I got lazy in going back to read it...again I apologize.