NoPistons -Mazda Rx7 & Rx8 Rotary Forum

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- 2nd Generation Specific (https://www.nopistons.com/2nd-generation-specific-17/)

- - Coolant Leak? (https://www.nopistons.com/2nd-generation-specific-17/coolant-leak-29129/)

Im posting this for my friend who posts here...(for some reason he cant get to a comp)

He recently purschased a T2, and now its leaking some coolant. Its not a ton, but during idle it is a constant drip. If the car is off it doesnt hardly drip. It appears to be dripping from where the intake manifold bolts on to the rear rotor housing, right next to the turbo, just to the left of the transmission housing.

Any ideas what this could be?

If the turbos have the same general coolant route, then it's the water hose going into the top of the housing in the rear of the engine. That connection likes to leak, and the water either puddles on the housing and sizzles, or drips down right where you described. The hose in the NA comes from the thermowax on the throttle body, dunno how different the turbo is.

This could be an important thing to fix, because it's a fat hose that will dump all of your water pretty quick if it finally blows, AND it's tucked under the intake, so it's not something you could fix on the side of the road.

Probably one of these places:

That was for me.

So do i have to rip off my intercooler and intake manifolds to get to it? Anyone else have any thoughts on it?

Hello, I am Dramon's friend and came to look at his car today. As my name would suggest I only really know V8s and know nothing about rotaries. My friend and I who also only really knows V8s both looked at the car as soon as the leak started. The car had to warm up first for about five minutes or so for the leak to start, and we crawled under and noticed the only wet, dripping spot was where the tranny bellhousing would mount to the block (core? whatever you rotaries call it), and it was coming through a bolt. We both suggested that it would have to be a freeze-plug (super-turbo water-stopper? whatever you rotaries call it) beginning to crack and/or leak, ones infront of the flywheel (spinny-rotor tranny connector? whatever you rotaries call it) to be specific. That was the only reason we could think of water to be there coming out of one such isolated area where no fluids should be. It seemed to also make sense that as the water heated up and circulated more, that it would expand and force out of the plug, if it is indeed beginning to fail. I just wanted to post this as I strongly think this is the case and wanted my friend to have an opinion on that too.

Then again, since I don't know anything about rotaries, there could be no freezeplugs or anything back there, then I'd be dead wrong. Let's hope so, wouldn't want to see anybody go through unbolting a tranny housing and lifting an engine to get to a $0.15 piece... https://www.nopistons.com/forums/pub...#>/biggrin.png

theres a water passage going from the rear rotor housing to the lower intake manifold. It provides the coolant for the turbo, I suspect this is what you have leaking. There is an O ring that goes between the lower intake manifold and the rotor housing which is responsible for sealing this junction. If you cannot see the source but it looks like it's coming from between the intake manifold and rotor housing or somewhere around there, it's probably this. I have a photograph of the ports I'm referring to here:

http://pengaru.com/~swivel/cars/rx-7...w_IMG_1793.JPG

the opening above the studs on each rotor housing, thats the water jacket in there. The O ring fits into the recess. In the middle of the photo are the primary intake ports, so you're looking at where the intake manifold normally is. For those who know more about what they are looking at, disregard the 6 ports barely visible, this is a hybrid turbo/NA block, in just a mockup phase (nothing inside).

Quote:

Originally Posted by 1971ChevelleSSV8' date='Nov 22 2003, 07:38 PM

Quote:

Originally Posted by teknics' date='Nov 23 2003, 09:46 PM

[quote name='1971ChevelleSSV8' date='Nov 22 2003, 07:38 PM'] Hello, I am Dramon's friend and came to look at his car today. As my name would suggest I only really know V8s and know nothing about rotaries. My friend and I who also only really knows V8s both looked at the car as soon as the leak started. The car had to warm up first for about five minutes or so for the leak to start, and we crawled under and noticed the only wet, dripping spot was where the tranny bellhousing would mount to the block (core? whatever you rotaries call it), and it was coming through a bolt. We both suggested that it would have to be a freeze-plug (super-turbo water-stopper? whatever you rotaries call it) beginning to crack and/or leak, ones infront of the flywheel (spinny-rotor tranny connector? whatever you rotaries call it) to be specific. That was the only reason we could think of water to be there coming out of one such isolated area where no fluids should be. It seemed to also make sense that as the water heated up and circulated more, that it would expand and force out of the plug, if it is indeed beginning to fail. I just wanted to post this as I strongly think this is the case and wanted my friend to have an opinion on that too.

Then again, since I don't know anything about rotaries, there could be no freezeplugs or anything back there, then I'd be dead wrong. Let's hope so, wouldn't want to see anybody go through unbolting a tranny housing and lifting an engine to get to a $0.15 piece... https://www.nopistons.com/forums/pub...#>/biggrin.png

you ever seen a core plug (aka freeze plug)? they arent bolts, even you being "mr v8" should know that.

and the only thing different in rotaries is the engine, nothing is different with the flywheel or tranny or anything.

some people are so blind.

kevin. [/quote]

Let's use some critical thinking skills here. Obviously, the bolt is not the freeze plug. If a freeze plug 'in front' of the flywheel is leaking, it is going to drip down into the open space where the tranny and block meet. It will have a visible leak at a loose bolt. The bolt is where the tranny bolts to the block. There is no leak anywhere near the intake manifold.

There are some coolant hoses that run at the back of the engine. I would pull the intercooler and the upper intake off and replace them. It sounds to me like that is your leak.

You can get custom fit replacement hoses from either the dealership or Mazdatrix. OR if Dramon is racing in something like Autocross then he can join Mazdaspeed and get the hoses at discounted prices.

I would start simple. The hoses are your best bet. Not only is there a coolent hose for the turbo there is another that runs up to the intake upper manifold as well. That one is prone to leaking. Its a 15 y/o car and those hoses are probably factory installed ones. They are done.

I'll try and get some pics up later tonight.