I THINK I HAVE A COOLANT LEAK, BUT I AM NOT LEAKING COOLANT VISIBLY. ABOUT ONCE A WEEK MY "ADD COOLANT" LIGHT GOES OFF, SO AFTER IT COOLS DOWN I HAVE TO FILL THE RADIATOR BACK UP. IT SEEMS TO ME THAT IT ONLY APPEARS TO LOSE FLUID WHEN I DRIVE LOCALLY NOT LONG DISTANCE. I HAVE BEEN TOLD THAT I MAY HAVE A BLOWN SEAL, BUT I DO NOT KNOW A WHOLE LOT ABOUT ENGINES, ESPECIALLY ROTARIES. PLEASE HELP

 

PLEASE TAKE THE CAPS LOCK OFF! IT IS VERY ANNOYING TO READ THIS.

Now...
Sounds like a coolant seal is bad and the engine is eating coolant.

If your lucky it is just a bad radiator cap which is just pushing coolant out too soon. Check your over flow resevoir. If it is maxing out then you either have a bad cap or the coolant seal is bad and over pressurizing the system.

Another option can be that there was a big air pocket in your system and when you drove it hit the sensor making it think it was low.

 

If you have a blown seal, it will be hard to start, sputter on one rotor for a few seconds, spew steam out the back, then run OK.

The most common hard to spot leak locations:
1) A 3/8" coolant line from under the UIM to the fast idle thermo control on the TB.
2) The heater hose that connects to the engine under the oil filter area.
3) Like all cars - the water pump seal (check the weep hole under the fan shaft.)

 

my bad with the caps. Dig7ech-The overflow resorvoir has raised but it is not maxing. how can i check to see if it is the radiator cap (buy a new one?). what if it is an air pocket, does that mean that it is not really leaking fluid, b/c i am. SureShot- i wouldnt say that its hard to start but i think i may have heard it sputter (possibly only on 1 rotor, spew steam) before it runs normally. so if it is a seal how do i go about fixing it? are there threads posted on the procedure? Thanx 4 helping

 

Well if there is an internal seal that is bad then you will have to tear down the motor to replace it. there are pleanty of posts here regarding Internal coolant leaks just do a search and you will find them.

 

http://www.aaroncake.net/rx-7/coolentbuzz.htm

Has a good description in isolating leaks. Also see http://www.aaroncake.net/rx-7/cooling.htm

 

thank for the info ill let you know what i find

 

Yup get a new cap. Try to get an OEM one from the dealer ship.

If it's an air pocket then the sensor will go off. If you constantly have to fill it up a lot then ignore this idea

You WILL know when it's running on one rotor. It will sputter at start up and will almost die if you give it gas. Until the rotor chamber clears and starts firing.

If you blow a white cloud at start up or have white smoke coming out while idling then it's a seal.

You can tell if you have a bad seal by pulling one of the spark plugs from each hosusing and checking if their wet.
You can also have some one turn the engine over while the EGI fuse is pulled to see if a mist of water get's sprayed out.

There are 2 ways to fix this bad seal.
The right way and wrong way.

Right way: Save for a rebuilt engine. No getting around it. You have to pull the engine and pull it apart to fix this.
www.rotaryresurrection.com has the best prices and shipping isn't bad.

Wrong way: Get some Copper block weld and put it in your radiator. Search the forum for the righ tprocedure but pretty much it seals the coolant rupture. This will almost always prevent you from using this engine from ever rebuilding it.

BTW. Both of my RX7's blew their coolant seals.
One drastically in under seconds and the other over a 2 day time period. So I know the common symptoms.

 

You know....sometimes the coolent will leak right out of the water pump.

If you look below that water pumps pully there is this little hole called a "weep hole".

Typically when a water pump is damaged or its bearings and seals are worn out for whatever reason it will leak from there.

Surprised that no one mentioned this first.

As to whether or not this causes other coolent seals to blow is anyones guess. I've heard, but not so sure, that if the water pump begins to have problems and is "weeping" this can over pressurize the system thus causing a seal to rupture at its worn and weakest points, internally. Again, not sure about that...But.

That's my 2.

You can check the weep hole with one of those pen mirrors, its like a dentists mirror, that allows you to look
underneeth the pully from up top. Its on the water pump at directly 270 degrees, below the pully, kinda tucked inside. Sometimes it can be hard to see because the pully is in the way.

One other thing is that it may only weep at certain speeds/rpms. So if you run it at idle and nothing comes out, you may not notice any leakage until you hit all the variable bands, namely round town driving.

It can leak very very lightly.....I freaked because I thought I had coolent coming directly out of the block by the spark plugs.

Turns out that I had to remove the water pump before I discovered a very light leak.

So Hypothetically speaking,

It seems that it can leak at a rate, when you're say, driving in 5 gear. And for whatever reason you get into town and only hit 3rd and it stops leaking (or vice versa). Then the fan blows the water pump dry eliminating the evidence BUT you notice a little bit of fluid that's along the bottem of the oil pan leading you to think where in the hell it could have come from.

Hope that helps...

 

The block seal or weld works great. I know from experance. Just makesure you follow the directions and it should fix your problem.

 

Cooling system sealants work for very mild leaks. just follow the instructions.

But Im not sure what it can damage.

someone mentioned here that it will make the engine unrebuildable?

Please clarify this for my own and others knowledge.

Thanks.