Preventative maintenance to prevent damage after overheating engine.
 

Two days ago I took my boosted Miata out for a drive on the freeway and white smoke came bellowing out of the engine bay when I turned into my exit. Turns out the overheating was due to a cracked vacuum cap on my coolant reroute, which caused coolant to leak. Temp gauge was maxed out, and I had to tow the car back home. Car starts and idles fine, I put in new coolant and replaced the vacuum cap, but I’m unsure about what to do next before taking it out on the road again.
Is there any preventative maintenance I should do to my car after overheating my engine?
Any signs of damage I should be looking for?
appreciate any help thanks.

Did you burp the coolant with the yellow magic funnel?

Nope I just put in coolant and topped it off once the car reached operating temp. What funnel are you taking about exactly?

Emilio talks about it in one of their old videos, Lisle 24680. It's pretty handy.

10:45 in the video.

Yep go get the magic Lisle funnel. I think most Advance/Autozone have them now. Generally when I burp my cars coolant system I follow these steps.

1. Lift front end as high as possible in the air.
2. Install funnel on the radiator fill spot.
3. Put distilled water and coolant in until funnel has some into it.
4. Run the car and let the fans turn on and off 3 times. Make sure the funnel always has coolant in it.


This is how I verify that I get all the air out of my coolant systems.

Alright sounds good I'll definitely be doing this. Anything else that needs to be done after over heating an engine?

You could try a compression and leakdown test just to verify that nothing bad happened. I also used an engine block tester kit to make sure no exhaust gasses were escaping via the cooling system after I overheated my car.

You could test compression and leakdown but thats just going to tell you how fucked up things are if there's an issue.
It's possible nothing happened, especially if you turned things off right after the event.

Cars are funny things sometimes. I had the exhaust off to machine the manifold-to-head face, and on re-assembly didn't refit or re-tighten the clamp on the heater outlet on the back of the head. Probably the latter as I drove it a bit after the job. Went out on last new years eve, hit the highway and accelerated into the traffic, when I noticed a slight smell of coolant. Pulled out to pass the car in front, smell went away, felt sorry for him ... but after about 4kms at 120kmh, something made me pull up and lift the bonnet. No coolant, but none of the usual signs of overheating either, just the end of the heater hose floating around the back of the head, the loose clamp still on the hose, and coolant all over the firewall.

Long story short, trailered it home, where it sat for months before I could work up the courage to see what damage had ensued. Fitted the hose AND tightened the clamp, filled it with coolant, hit the starter, and it fired first revolution, and sat idling like nothing had happened. No bubbles, no overheating, just an occasional small water loss. Put several thousand kms on it since without any drama, and I have entered it for a supersprint at the end of the month, which will be the acid test.

TL;DR Miracles happen. I have seen one.

The obvious answer here is you must K swap after you overheat a BP engine.

Am I the only person that doesn't have a problem filling up a coolant system?

Lift front in air, fill with coolant, leaving the cap off. Keep adding coolant as it gets sucked into the engine and let the car come up to temp. Stab the throttle hard a few times to get the coolant moving. Shut off, let cool all the way down. Top off. Good to go.

My NA6 has always bled itself through the overflow as well. I honestly don'y know how people have trouble with these? (The magic funnels are great though. No mess.)

I've never even bothered to do anything special with a Miata. Leave it on the ground. Fill it up. Run it. Let it cool. Top off. Done.

Very stupid question....Any potential to have an oil starvation issue with the front end jacked high up?

I don't see how that could happen on a miata unless the car was extremely low on oil.

No because the sump is on the "rear" of the motor, so you'd be more likely froth the oil with the #3 cwt's beating the oil.

Steam is not smoke.