Hey guys,

Just bought a '90 RX-7 convertible yesterday... And just noticed that it has a serious smoking problem.

When I bought it the guy told me there is some minor smoke at start up but it goes away quickly...

He was right, but I wouldn't call the smoke "minor".

When I started it up this morning it put out so much thick white smoke that I was afraid someone was going to call the fire department...

It only does it for about 5 minutes, but it's a TON of white smoke...

I have done some searching on this problem, I'm guessing it's the cooling system leaking into the combustion chamber?

I haven't noticed any drop off in the cooling reservoir yet. I'm also a complete idiot when it comes to cars.

It runs and drives great when the smoke stops. The smoke is a major problem though, kind of pisses off the neighbors and I'm guessing it's not a good thing for the car.

I really don't want to invest in a rebuild at this point... If it's necessary I'll probably just sell it.

I'd really like a temporary fix, however temporary it may be.

The guy I bought it from said to change the oil and put in a half quart of automatic transmission fluid...

I've also read about buying some special gunk and running it through the cooling system.

Any ideas or advice? Is this a serious problem?

Thanks,

-Scott

 

UPDATE:

I tried the fix posted on another thread in this forum... The Alumiseal in the radiator thing.

I also added some ATF to the oil as suggested by the guy I bought it from, although I seriously doubt this is an oil issue.

I'm not noticing any significant leak in coolant, but so far the smoke problem is still there.

And for about 3-5 minutes on a cold start, it's a TON of smoke... Very similar to what's happening in this vid: http://www.youtube.com/watch?v=UOIbA...eature=related

So I'm guessing coolant seal failure... I just dumped $2k into this car, it has 100k miles on the engine, and aside from the smoking and some minor hail damage on the hood, it runs great.

Did I get a shitty deal? Is there ANY way to fix this without spending $1k+ (Because I honestly don't have it)...

Any ideas? Any help is much appreciated guys.

Thanks,

-Scott

 

I guess I'm SOL.

The problem seems to be getting worse, smoking for around 15 minutes now instead of 5 minutes...

So I blew $2k on a worthless car... Or am I wrong? Anyone?

Thanks.

 

wha clor is the smoke

 

It's thick white smoke, exactly like the video I linked to.

Thanks.

 

First, NEVER EVER put ATF in the engine oil! It is NOT a lubricant and will EAT many of the rubber seals found in the engine.

Also DO NOT use sealants in the cooling system. The "coolant seal fix" is simply a last resort option if you have no other choice (like you are stuck at the track). All the writeups conveniently forget to mention this fact. That junk will clog half the cooling system and make cleaning up the engine for a rebuild a very unpleasant experience. Have fun with the clogged heater core.

If the smoke is sweet smelling, it is coolant. This will also be accompanied with a noticeable coolant loss.

A great test is to just check for bubbles at the rad cap. With the engine DEAD COLD, remove the rad cap and start the car. Do you see a steady stream of bubbles coming from deep in the engine? Now rev the engine. Do the bubbles increase or does coolant gush out? If so, then you are pushing combustion gasses into the coolant and thus have a coolant seal leak.

But if you are not loosing any coolant, then it's not going into the engine.

 

Thanks Aaron...

Alright, so it's getting kind of interesting now.

Last night I cold started it, and it smoked really heavy for like 20 minutes, the worse I've seen it so far...

This morning, I cold started it and it put out a small puff of smoke, and then didn't smoke hardly at all. I'd be fine with the car doing this (I know long term I probably need a new engine, but temporarily it's fine).

I did the champagne test and didn't see any bubbles. I'm also not losing any coolant at all.

So, the smoke is white, has almost no smell, I'm not losing coolant, not losing oil, what could it be?

I'm thinking maybe the stuff I put into the radiator is starting to work, if only temporarily. Anyone else have any ideas?

Thanks,

-Scott

 

I'm gonna go with a sticky/leaking injector.

Do this:

Engine dead cold (Like parked overnight) remove the spark plugs, disconnect the CAS, and crank her over for about 15 sec. (You can place a paper towel or rag over the plug holes. This will assist you in identifying the liquid.)

Replace the spark plugs.

Fire it up. Smoke should be greatly reduced.

Check the rag. (If you did not use a rag, check whatever's sprayed all over your engine bay.)

 

The coolant seal fix that I posted (alumaseal) has worked great for several people. I've been running my motor for over a year now without any issues. This is my daily driver and weekend racer, so it definitely gets it's use. My repair has lasted for nearly 10K miles now, including a trip down to North Carolina for the deals gap event. No problems at all. And this was a motor that was pumping coolant out the tail pipe as fast as we could pour it into the radiator.

The only reason I could see this not working is if you are blowing exhaust into the radiator, which might keep the sealant from getting to the seals.

You probably just needed to give it a little more time to work. I would expect your motor to continue to improve over time, provided you still have the Alumaseal in the radiator.

Oh, and ATF in the motor was a bad idea.

 

Thanks for the tips guys...

Okay, so, without sounding like a total retard, when you say CAS are you talking about the Crank Angle Sensor? Again, I'm not the brightest when it comes to cars, especially the rotor engines.

Thanks,

-Scott

 

Okay, the smoke looks like steam, it's white and odorless...

I'm not losing ANY coolant at all... The problem is still there. Could this be transmission fluid?

Again, the smoke is white, and there's TON of it... I don't know what it could be burning. Anyone?

Thanks,

-Scott

 

Unless you have a bunch of water in your gas tank, you have to be loosing coolant....

 

yeah white is most likely coolant, run a compression check for sure asap.

 

if you arent loosing ANY coolant at all...
you have to be losing something (burning some kind of fluid to produce the smoke)
maybe its deeper than that but i wouldsuggest team troubleshooting w/ a mechanic. or posting up compression numbers.

 

I know it sounds cliche but it sounds like with 100k on the engine its time for a rebuild. other than that everyone else has covered anything else i'd think of

 

if the previous seller just opted to put in 100% Water, there won't be sweet smell with Coolant Seal failure.

It is a gradual failure, water seal.

Compression test will likely show the number above the minimum if the water seal is at fault.

by all infos in here, sounds like water seal.

 

If it doesn't smell sweet then I doubt it's coolant.

You mentioned the car was an automatic? It could be that the vacuum modulator has failed and ATF is being drawn into the intake.

 

Okay, THANKS for the help guys!

Went out yesterday, completely flushed the radiator, refilled it with water, flushed it again, bought some more Alumiseal, put it in...

Start it up cold, and... It smoked for a solid 30 minutes, was at a friends house, he was worried the neighbors where going to call the fire department.

So, I'm about to the point where I just want to part the car out. I had dropped everything I had in my "car fund" into this, because I was led to believe that it was in good working condition and would make a good daily driver.

The building sized smoke plumes where putting a damper on that. (I've talked to 5 cops about the smoke so far.)

So I go out this morning to give it a start, I'm all ready to deal with cops/fire department whoever decides to show up...

I crank it over, wait for the smoke, see a quick white puff, and then nothing. It warms up with no smoke at all...

I was worried that maybe the coolant had leaked out or something, but it's all there. So the Alumiseal is appearing to work, if only temporarily.

I drove it around for about an hour just to make sure the coolant system wasn't completely clogged up or something. It runs awesome.

Which is GREAT. I was really getting frustrated, I have another car that I was planning on selling but couldn't because the RX-7 was smoking so severely.

Even if it is only temporary, it'll give me enough time to save up for a rebuild.

Really appreciate the help guys... If there was a "thank you" button, or a "Buy Me A Beer" button I'd be all over it.

Thanks again for all of the help.

-Scott

 

I wouldn't leave just water in the cooling system for very long. The JDM engine we started with for our turbo vert conversion had a coolant leak into the front rotor. The iron in the water jacket had rusted thru causing the coolant to leak into the front rotor. "Anti-freeze" is more accurately described as "anti-rust".

I'd also use distilled water with the anti-freeze instead of from the hose. That way you start with less calcium, magnesium and other minerals that will build up inside the water passages.

Good luck with your project!

 

Glad you got the smoking under control. And like I've already said, I've got over 10K miles on my "temporary" fix.