I am wondering if my coolant seals are leaking into the engine. I am pretty sure I need a rebuild, but I want your oppinions. I took off the coolant filler cap and let the engine run, it was fizzing (meaning exhaust is leaking through the seals into the coolant, bubbleing at the top).

I took a picture of the exhaust coming out of the tailpipe right after start up.


I also figured that if the exhaust was leaking into the coolant while it was running, then when I shut off the engine the pressure from the coolant system would leak into the engine. To check this out, after I let it cool down and sit for a while. I then pulled the bottom spark plug off and checked to see if it was wet with coolant. The spark plugs showed signs of carbon build up, but they were dry.


Also a two days ago I installed my Hi-flow CAT. I started the car and had a exhaust leak between the Downpipe and the Hi-flow. This was ok because I would just stick two gasgets in there. But, After a while I noticed a green drip come from the leak.

I am positive none of the things I have listed here are good. I am just curious what steps I should take next and how I should go about the engine rebuild/replacement.

Thanks.

 

coolant is getting in through your turbos, your engine is fine

just my $.02

 

Why do you think the coolant is getting through the turbos?

By the way, this engine has 97,000 miles on it

 

Apart from the green drip you mentioned, I would suspect that most (if not every) car makes steam in the exhaust when it's cold outside. Especially when it's cold enough for snow, and you've just started it!

 

Your plugs would have a slight tint of green if it was burning alot of coolant. The exhaust gas would also be very white. All rotarys exhausts are steamy in the winter they run hotter than piston engines.

What does your oil look like?

 

This is my other post on my oil. It has PICS.

https://www.rx7club.com/forum/showth...hreadid=159283

 

That's normal on start up..When coolant leaks it is like a mesquito truck...you wouldn't see the other car in your garage...

 

I am not 100% sure about this, but I do not think it is really possible for coolant to be leaking into the turbos unless you have a cracked turbo housing. That would be almost unheard of. I am not saying it is not possible, but highly unlikely.

If the engine has 97K miles, you see bubbles/foam in the filler neck when the cap is off, you are using coolant, and you have excessive amounts of white goo in the oil filler neck (a small amount is normal), I think you may have a problem. Does the steam you get on start up smell sweet? Like antifreeze?

Sounds like an o-ring failure, but be sure to rule out any other places you could be loosing coolant. Has the car been overheated recently? The car has been overheated if the temp. needle moves above horizontal at all.

Jeff

 

The car has not been overheated recently or ever while I have had it. The steam I get has had a faint smell of antifreeze on occasion. I will keep testing it.

 

The fact that you are getting bubbles out of your filler neck pretty much confirms that you have bad coolant seals. Add this to the fact that your exhaust smells like coolant...

You might want to look into that CRC Blockweld (?) stuff.

 

Try an overnight leakdown test to confirm the presence, and determine the location and extent of the coolant link.

Put the front end on jack stands. remove the belly pan so you can see all the coolant hoses.

Warm the car and pressurize the system with 12 psi. Let it sit for 12 hours or so checking and charting the readings on the pressure gauge every hour.

As decrease of pressure over the 12 hours is indicative of a leak somewhere. Get under the car and look for hose leaks. (I know you are worried about coolant O ring leaks but if the leak down test shows a pressure loss, you have to rule out leaky connections as the cause of the pressure loss). If there are no hose leaks, then you have the dreaded O ring failure. In that case you have two options. Assuming you are in the early stages of the failure (slow deprerssurization and the O ring failed at a low pressure position in the combustion cycle) you can try any of the many stop leaks. In my first fd I tried a half a tube of Aluma-seal leaving it in the system and the leak did stop----of course 10K miles later the car burned to the ground (probably not related but I just thought I would try to make you nervous).

Overall, you sound like you have the early stages of the problem. When you have the full blown case of the problem, you will know it because you will be unable to drive the car 5 minutes before the temp tries to go off scale. You may or may not see the mosquito truck cloud but you will smell the antifreeze.

Good Luck

Jeff

 

Yes, if your car was truly leaking coolant into the housings you would know it. Your car would closely resemble a mosquito truck. The smoke would literally swallow up your car. I've seen it happen and it's quite impressive to say the least.

Your exhaust would also smell very sweet like coolant. Stick your nose up to the tail pipe and test-sniff it

 

I made my neighbor's house *completely* disapear with a leaky O-ring. My piston powered daily driver makes more steam when it's below 50ish than what is coming out of your tailpipe. I also agree that the coolant would have a pretty torturous path to make it to your turbine housings.

My suggestion on the drip from the exhaust is that you may have a coolant leak externally near the turbos which runs down the exhaust and drips off the gasket. If you had enough leaking into the engine to condense in the exhaust it would certainly steam more than it is in the pic.

Alex

 

i would not count out that your turbos may be going bad, my interconnecting support spindle that connects both turbines snapped and i had a huge amount of white smoke out the exhaust, my engine was fine, try to determine which it is before going any further, see if you are running the full boost pattern if you have a boost gauge.

 

Just keep in mind that white smoke is much different than steam. White smoke under boost is a sign of turbo death, but it is not from coolant leaking into the turbos.

 

I've been through exactly this 3 times and I believe it's your engine......coolant seals gone. That smoke is identical to what I was seeing as well as the condition of your spark plug........identical. Also, once you see the Champagne bubbles in the coolant filler neck while your engine is running.........you need no more proof. That is combustion gas getting into your cooling system. I've seen it firsthand 3 times unfortunately.......HAYES ROTARY SUCKS ***.

 

Mesquito truck is a good analogy.

 

wow you brought this one back from the dead

 

mine did this on my turbo II, i thought it was the internal coolant seals. It ended up being my internal and external oil seals on my turbo leaking massive amounts of oil into my motor and out my exhaust.l

 

Wow this is old.

I just had my engine rebuilt. It WAS the water seals. The seals were flat in places and they were leaking. I agree with badass7. If you see bubbles, then it is your water seals.
My apex seals were also a little soft in places.

I will have pics soon.

 

My plugs looked exactly like cowsniper RX7. The front rotor had more rust than black carbon on it though. No smoke out the tailpipe even though it was sucking down 1 gallon for every 11 miles.

 

So who did the rebuild for you ? I assume that engine failure was on your original motor ?

 

RX-7 Heaven

www.rx7heaven.com

 

Here is the rebuilt engine waiting for a T04S