ben_stevo

I have just bought a 1993 fd3s and it has a bad water leak. Once you stop the engine and open the bonnet you can hear the water boiling, Like you would in a kettle, The water then leaks after a few mins, the water ends up on the floor under the centre of the engine and at the right hand side it leaks out of a split in the hose that goes to the overflow bottle. Then when re starting the engine the bleeper comes on along with the red light that says add cooland (obviously)! The engine temp needle never goes above half way though? Any ideas? Im new to the rx7 world as I only purchased it last week and havnt got a clue on these cars. Could anybody tell me where to source the thermostat(s) and first of all i will check those. Any suggestions would be greatly appreciated. Thanks

Mahjik

iTrader: (1)

OEM t-stat: Malloy Mazda , Ray Crowe is the parts manager, gives great prices to RX-7 owners, quick shipping:
(888) 533-3400 , (703) 490-8170 , fax: (703) 490-3864 , hmkparts@aol.com

As for your symptoms, it doesn't sound good. I would start with the t-stat. but your signs sound more like a coolant seal failure.

EDIT: Oops, you are in the UK. Basically any place you can get an OEM t-stat is good. I believe Ray at Malloy can and does ship internationally, but email him to find out for sure.

ben_stevo

Thanks for the help, Il email him now. How much are t-stats and what are they? Lol! Also have you got any idea where the thermostat(s) are???

rynberg

Hmm....perhaps you should find a shop to do the work. It sounds to me like you have a bad radiator cap or just some split hoses. This is fairly basic mechanical work so if you have to ask......

If you are going to proceed on your own, please take advantage of the stickied threads at the top....you can download the factory service manual and read the FD FAQ.

ben_stevo

To be honest I would rather take it to a garage and pay someone alse to do it but finding places in the uk that work on rx7's is almost impossible! The only place that will work on them is the mazda dealerships and they charge a fortune as most of the mazda mechanics know nothing about them! Over here they are a very rare car, I have only ever seen 1 on the road before I got mine. I would try and have a go myself but I have looked and looked where the leak is coming from in the middle somewhere but just cant quite see without taking it to bits!

rynberg

I understand your concern but a good mechanic should have no problem with doing work on the coolant system. That side of the engine bay is pretty straight forward. If you are still leery, then I suggest you read the service manual and use the search function here to learn more about the car.

If you have never worked on cars before though, you can easily make a bigger mistake than any mechanic you'll take the car to.

Montego

iTrader: (1)

I had that exact same problem. Turned out to be that the AST wasn't sealing properly.

1)Clean the filler neck and AST areas where the caps seal. Replace both of your coolant caps. Use OEM caps. If the problem goes away and never comes back you know you had bad caps.

2)if the problem comes back after a little while. Replace AST.

3)if the problem never went away it is a possibility that you have a pin size leak on one of your hoses. Have a shop try and find it.

gurgleing coolant = air in your system. Needs to be burped.

welcome to a world of hurt. Use the FAQ it will only help you.

dlarson101

Are you sure it's not the AST that this hose goes to. Do you have a Picture?

Larz

Clamp the lines that go to the overflow. That can result in a pressure leak, also.

dradon03

iTrader: (2)

I have seen several videos from London with like 10-12 Rx-7's driving toghether there must be a local club somewhere that can help you. Maybe the best idea would be to get the whole coolant hose kit that is on special right now.

At 160$ it is a good reduction from stock Mazda prices and since you are international getting everything once and doing it so it is done helps.

FDZero

iTrader: (10)

He lives in UK so I I think he has the RHD models/configuration.

ben_stevo

Yeah I have the RHD model. There is specialists in the uk but theyre is many and non of them are near me and they wont tell you anything without ££££! The hose that is leaking is the hose that comes down from the filler cap from the overflow tank. its just the hose that connects the filler cap to the tank and if im right this isnt pressurised. Somebody in the uk told me it could be the thermostat but I dont know where to find it, usually in most cars iv worked on it is just clamped inside a hose somewhere in the coolant system but I cant find it. And when you guys talk about AST - whats that? Also which way round should the caps be as I have the pressure release cap on the tank on the left handside and im sure it should be on the tank in the middle.

ben_stevo

Had a go at it this morning, after speaking to a mazda garage they told me where the thermostat was. I took the middle tank off that holds the thermostat and there wasnt one in it! Can this be a problem?
Also does this tank need resealing with gasket sealer?
Could this tank of been where the leak was???
(the tank im talking about is the middle filler tank where the belts and pulleys are)
I have ordered a new t-stat from a local garage and im collecting it this afternoon. Any help in the meantime would be much appreciated.

Also does anybody know how to drain the water from the system? And what the coolant to water ratio should be?

dradon03

iTrader: (2)

Without a thermostat there would be a hole in the side of the thermostat housing, I think we can both say that this would be a serious problem.

From memory I drew something up in paint it is crappy but should give you a general idea.


I don't remember what side the thermostat is on but this is what I could remember.

It is safe to run 50%coolant50%water, not the tap kind the grocery store kind.

www.fd3s.net would be a good website for you to look over it will give you many tips on how to do small stuff.

Buckman66

ben_stevo. Sorry mate you didn't look very hard. There is a very active rotarty club in the UK that can provide you with all the expertise you will ever need. http://www.mazdarotaryclub.com/forums/

There are also 6 or 7 major workshops that specialise in the repair of RX7's. WGT Auto Developments who are arguably thee specialist, are only a short trip down the M62 from Leeds ( 75 miles ) . Many of the specialist's are active in the forums, so you will get all their advice from free.
Join and support the mazdarotaryclub, all you need to know ...and so much more.....

Bob( UK )

CantGoStraight

If there's a noticable split or crack in the hose that runs from the AST to the recovery tank then this needs to be fixed first as it will never work correctly. You will push coolant into the tank when hot but it will never return to the system when it cools (leaving your coolant system down) and this will then allow air to get into the system and the sounds you now hear are just that. The temp gauge will not move past half way till it's a real problem (then usually it's too late). If your not going to take the time to learn about the car and how everything works you may as well sell it as you find your self left on the side of the road trying to operate it in it's current condition and worse a damaged motor before it's over with.

ben_stevo

I havnt really looked for any specialists outside of leeds as i have only had the car a week and its the first problem ive come accross. I have taken the middle tank out today (is this the ast?) and i have installed a new thermostat, and then sealed the tank back on with gaskett sealer. I have also put in a new air filter as it was black!!!
I put about 4 litres of coolant into it and then just carried on filling the system with water (I used the tap type, is this a big problem, a local mechanic said it would be ok but he doesnt know much about these cars) I continued filling until the middle tank was full and the tank on the passenger side was about 1-2 inch from the top. It didint seem to take alot of water though.
I took it out for a 5 min drive, admittidly I drove it like I stole it, it seemed to drive fine, When i got back home the car started making the bubbling noise again when i popped the bonnet. I looked at the overflow tank on the drivers side and there was coolant bubbling out of the little hole on top of the tank just next to the filler neck.
It seems like there is still air in the syatem, is there a bleed nipple?
The leak from the middle has stopped and i sorted the leaking hose. The only 2 porblems now are : boiling water.
coolant overflowing from overflow tank hole.

XxMerlinxX

iTrader: (2)

Brilliant. We tell you NOT to put tap water, but what do you do? You add in tap water. Listen, you're in over your head. Plain and simple, you don't know what you're doing with this car. This isn't your mom's accord that you can go and beat on, then change out the intake and feel like you've accomplished something. This car requires careful attention to detail, and if you're not going to listen to us, you might as well go turn up the boost as I high as you can and go for a spin, cause your car's not going to last much longer anyway.

rynberg

You should run a 40-50% coolant mix. AND NO TAP WATER! Distilled water only!

Why didn't you download the free service manual from the link I pointed you to? Did you install the t-stat correctly? If you're going to do the work yourself, you've got to be prepared!

There is nothing wrong with not knowing how to work on your car. Check out Buckman66's post....let a mechanic look at it before you ruin the motor. Please.

ben_stevo

I dont know why you all run your cars on mineral water over there but I called mazda themselves this morning and they said that there is nothing wrong with tap water aslong as the mixture with coolant is correct. Yesterday I put tap water in the car before dradon03 even said put the store type water in the system. The car is now at mazda and they are giving it a pressure test for any leaks in the coolant system and whilst its there it is getting a £500 service. I have worked on my own cars all my life but this is my first attempt at a rotary engined car. I admit I know nothing about these and thats why i did try to download the free service manual and it wouldnt download it!

CantGoStraight

If your going to run tap water in it then the minerals in the water are going to contribute to the deterioration of the motor. We run "DISTILLED" water (mineral free) to help the coolant do it's job (sacraficial metals in it to prevent or lessen) electrolosis, the coolant shold be changed frequently and depending on your local temps (here in FLA. we run a higher % of water to coolant) with water wetter or equivilant. The boiling sounds mean you still have air in the system and it needs to be "BURPED" the recovery resivor will continue to over flow till you get it to the correct level (hot or cold) you choose where to correct the level of the tank.

dradon03

iTrader: (2)

Everyone led you the right way and you decided to listen to Mazda.

Sorry but this calls for a WHY THE FU$% did you ask for advice when you weren't even going to listen to it.

Mazda knows little to NOTHING about this car. You just lost 1,000$ when you could have gone to a rotor shop and they would have done it not only cheaper but with more knowledge. You could have used that money to order all the parts everyone told you and got them installed by a rotorshop in your area I am sure. You sir are plain stupid and noone on this forum should waste time giving you advice if you are going to throw it out the window because you have worked on all your previous cars and think you know better.

Heck when I am at the grocery I even look for water with the lowest PPM content. Let me tell you I know someone in my area who takes care of his car but at every chance does as you say drive it like you stole it and he has been through 4 motor is as many years.