The 4 stages of coolant seal failure.
 

The 4 stages of coolant seal failure.

Stage 1: Denial.

How can I possibly have bad coolant seals? My car only has 62K on it. It doesn’t smoke. It starts easily. It runs great. I have taken very good care of it. Never overheated it! Never road raced it! All of a sudden, I am getting coolant overflowing from my overflow tank, and a low coolant buzzer the next time I get in it to drive. It must just have some air in the system that has to be purged. Yeah, that’s it!!!! I just need to fix something else. I can’t possibly have a bad coolant seal.

Stage 2: Anger.

Ok, I pulled out the fucking overflow tank & cleaned it out. Still blowing coolant from the overflow tank! I checked all of the damn coolant hoses. No leaks. I zip tied the lines to the overflow tank. No help!!! I checked the filler neck for bubbles to indicate to seal failure. No bubbles. WTF!!! Still blowing coolant! I replaced both caps. The damn engine isn’t even running warm. I can’t possibly have a goddamn bad coolant seal!!!

Stage 3: Acceptance.

I took the car to a Rotary Specialist. They confirmed the problem. I have a bad coolant seal. Shit!!!!

Stage 4: Visa card.

The car is at the mechanic for a rebuild. No way that I am doing this one myself. I’ll be getting new rotor housings, and a mild porting job, along with everything else that comes with the $5500 price tag. They estimate it will take 2-3 weeks to get it done.

I’m considering getting bigger secondary injectors. My friend just went thru this same thing last year. His injector duty cycle is about 90% with stock injectors, and 300 rwhp. My car should be about the same power when done. I’m foolishly hoping that nothing else will need to be replaced once things are taken apart.


I have come to the conclusion that coolant seals fail for two reasons: Heat and age. If you beat on your car, your seals will fail sooner. If you are good to your car, your seals will get old, and fail due to age. I have seen a number of threads lately that lead me to the conclusion that at 15 years, its getting near the end of coolant seal life, regardless of miles. A couple of members: “Theorie”, and “Goodfella’s” father are among several who have had failures with pretty low mileage. I suppose that this is my warning to anyone on original seals: Be prepared, your days may be numbered.

im at stage one currently.

im thinking of upgrading slowly but i might just go all out and head straight to stage four.

stage 4 sounds good with a gt35r ;)

Adam,

I think you and I went through the exact same stages.... :).


I plan on doing the r&r myself though, as I hate the idea of someone else wrenching on my ride.


good luck dude

How many miles on your seals?

Thank you :)

Just over 80k on the seals. I am starting to suspect the previous owner used some form of stop leak, as there is a lot of crap floating around in my coolant even though its been flushed twice. I say this only because I bought the car at 73k, and I have a feeling the seals were toast even then.....

at stage 3 myself. gearing up for stage 4 :icon_no2:

If he used some form of blockweld treatment the color of the crap will be copper colored. If the crap is black this is usually carbon or oil blow by.

I'm at stage 3 saving up parts for stage 4 =/

A few things about this. The FD seems to be a bit more prone to this sort of failure. My theory is that it runs hotter than the FC and older stuff. May want to try an FC thermostat.

The symptoms:

- After the engine has been shut off and the car has been allowed to sit overnight, once there's an attempt to re-start it, it will start on what sounds like as one rotor, blows some whitish smoke out, and sounds like a lawnmower. About 10-30 sec later, it will suddenly come to life. This happens because, when the engine is warm and has just been shut off, the pressure in the cooling system is greater than what's in the combustion chamber and coolant in the system will flow into the chamber and fill up the bottom of the rotor housing. The next time the starter swings the motor around, that coolant fouls the plus.
- Over-flow tank fills up and spews coolant out. May also suddenly suck it all back in.
- Loss of compression if the original overheating was bad enough to flatten seal springs.

Lastly, read this before considering aftermarket options:
http://www.nopistons.com/forums/inde...howtopic=67208

Overehttop, send me the engine to rebuild. Check my site per my signature for more information.

B

My crap is mostly black. I also found a little teardrop shaped rubbery silver thing floating in the coolant. :dunno:

lmfao... nice write up..... someday I will succumb to this, then I will go big.... or just go home.
:P

Where are you getting the work done, Adam? I need to visit a rotary specialist down here soon...


randy

I think I'm in stage 2. Except nothing pops off. Just my coolant is always dirty. Even after radiator cleaner, and flushes. My coolant will have gunks of what looks like mud. It's soft, and greasy. Looks almost like shit in coolant. I'm at 82,xxx miles on original motor.

Hi Randy,

There are no rotary specialists in the SLO area. The closest is Mariah Motorsports in Santa Barbara. They are kind of expensive. I took (drove) my car to Rotary Reliability & Racing in Santa Ana. I bought a motor from them for my 82 GSL (many years ago). It was well built, so I went back to them. The owner, Nick, is a good guy, and has been building rotary engines for over 25 years.

For those with failing seals, please list your mileage.

Thanks, Adam

Thanks a lot, I'll be sure to check it out because there are multiple minor things wrong with my car right now that I'm sure will only get worse in time.

As for my car, 94,xxx is the count. (Oil in my reservoir tank.)

Randy

you're pretty much right on, with higher performance rotaries the seals are abused more and more likely to fail on their own. older motors that have been overheated generally crack irons and show the same symptoms. FDs do run hotter as at times there is no air across the motor and radiator so they are more prone to those failures as well vs the older series motors.

one thing i really did not like change wise over the series is how the coolant seal groove was moved to the irons vs the rotor housings, the older motors were near bulletproof for coolant seal failures but had plenty of wear issues and oil seal issues, however they ran for much much longer even taking into account the differences in performance and had a completely different set of failure reasons.

Make sure you remove the rad and hose it out to try to get all of that out. I removed my rad recently and found remnants of that crap just hanging out in the bottom. Must have been in there from 2 motors ago.

Don't forget to do a FPD while you are there and maybe some new fuel and coolant hoses.

Sorry to hear that. Mine's got 58K on it. I'm crossing all fingers and toes...

There's a third reason for coolant seal failure: Corrosion in the areas in contact with the seals. IIRC, that's what got Goodfella's dad's seals.

Dave

Removing the radiator and cleaning it out is on my list of things to do. I have already replaced all of the coolant hoses as well. In my other thread (warmup/coolant issues), I listed some other things I was considering replacing while the engine was out. I really would like to replace all hoses, gaskets, and seals to ensure that the rebuild lasts at least another 80k.

Mine started about 80k. Been nursing it about 1.5 years now. Surprisingly it's gotten no worse in that time (now 87k) but it will go under the knife this winter.
Adam, at the risk if side-tracking the thread.......are you going with OEM coolant seals on the rebuild?

Yeah, caused by not flushing the coolant, according to Goodfella.

Here's the link, because I think everyone should see what they are doing to their engines by not flushing the coolant anually.
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/results-not-flushing-your-coolant-686776/

Sorry to hear that. Once you have it back, it will all be good :)

Yep. I don't drive the car that much, maybe 2-3K per year. If the OEM seals go another 60K, the car won't need seals for 25 years :D

I'm at the first stage...

Hi Adam! Long time no talk. Sorry to hear that your coolant seals blew. Are you going to go for OE seals or the ones from Pineapple?

I'm currently rebuilding my motor (again) and I'm going the Pineapple HD seal route.

Stage 5 - Going through stages 1-4 and realizing you don't have enough money to fix the car. It then sits for months or years until you get pissed enough to fix it, or pissed enough to sell it. Even if you get it fixed, you ultimately hate rotaries, but still buy the stupid cars over and over for some reason.

...been at that stage for years.

Thanks. I'm just going with the stock seals. Since I don't drive it alot, they should last at least another 14 years.

My add coolant light has come on twice in the last 3 weeks, but I only have 21,000 on the motor!

i feel your pain after buyin my 7 it took a shit after owning it for less than 1k and babying it most of the time

Adam

Time to invest all the millions you made on the cheep bastard air intake mod! (LOL)...

Good luck with the rebuild

Jeff

I rebuilt my motor (myself) after 80k miles (original engine). It blew the coolant seals on both rotors. Both chambers were full of coolant when I looked in the exhaust ports before tearing it down. When I was cleaning parts I noticed the coolants seals on the rear housing were real hard and baked on. It took a lot of work to get the old seal material cleaned off. So yes I agree it is heat (mostly) and age. The heat eventually hardens the seals and age is contributor too. I did overheat my motor a couple times too a few months before it blew.

So currently I'm at Stage 1 (for oil smoke when cold). But, I am sure its the turbo oil seepage into the exhaust. It can't be the motor! So I will stay at Stage 1 until I get around to pulling the turbos...then it will be Stage 0 I hope.

What about the pineapple coolant seals?? Aparently they outlast engines!!



=Ben

Reading this thread, I'm starting to believe I definitely have bad seals. Just when I think I've got everything working correctly...