KA coolant questions

Alright, my 95 ka24de is having some problems and I need a bit of help to address.  The engine is in a 95 S14 and its the original motor so no funky business there.  The car began overheating a month ago so we did the usual checks...tested radiator, new thermostat, new gaskets.  Radiator seems fine..theres no leaks under the vehicle and we ran a hose through it..no blockage.  We tested another radiator (S13 SOHC rad) w/ the new thermostat and we were still overheating.

Fast forward a week later when new parts arrived.  This time we were changing the whole system..car was never maintenenced in this area so even if its not "the problem" it still needed to be done.  A new thermostat (a different one..in case other one was shyt..you know) water pump, belt, coolant, and because the old clutch fan wouldnt fit on the new water pump..a clutch fan as well.

After installing all that, we fired her up...and overheated.  At this point Id been told it could be the headgasket by quite a few people.  What else could it be at that point?  So recently I just finished ripping apart the engine and putting her back together with a brand new headgasket (and every other gasket I could get too).  We had some timing and dizzy issues, but as of last night, I was finally able to get her to start up. 

After that great moment I decided to go inside and get fairly drunk...it was already late and the neighbors no likey open headers. 

Anyway, so this morning I had some time before work to try and get coolant back in the car.  Now, Ive read MANY MANY suggestions and googled the fuck out of putting coolant in your car as well as talking to all engine friendly friends and Im probably more confused NOW then I was when I first started but it seems you want to make sure the engine is cool, take off rad cap, fill radiator, then turn the car on and wait for normal operating temp.  Once operating temp is reached, the thermostat will open allowing the circulation of coolant.  Some people have said "leave bleeder cap on" some have said "take it out"...well this morning I took bleeder cap off and had the rad cap off.  I understand the coolant system needs to be pressurized...but how else do you know you should add more coolant? 
Another suggestion was, fill radiator, cap it, then keep adding coolant to the coolant overflow.  That sounds like a great idea, but my "overflow" is currently an old water bottle and hard as hell to get coolant in and out of. 

So I turn the car on, everythings normal (not really, but its running) and instead of reaching normal operating temp and stopping, it keeps rising and causes coolant to explode out of the top of the radiator.  Is this normal?  Am I incompetent in adding coolant?  Whats the proper proceedure and what could be wrong that i havent fucking fixed already?  This problem is bugging the shit out of me..specifically because it looks like I just tore down my engine and rebuilt it for what seems like nothing.  The only part of the cooling system I havent done anything to is flushing out the block and thats because I dont know how (though I doubt its to hard...what, take off rad and stick a hose in the upper radiator hose opening in the block?)

Any help on this is greatly appreciated.  Also Im having A LOT of upper timing chain rattle.  What could be the cause and solution to this?  It sounds like theres 1 more link then there should be and its slapping around in there pretty rough.

Sounds like you had a pretty nasty air bubble, and when the thermostat opened, coolant flowed.

Pop went that weasel.

I've never heard or seen of a KA having a bad head gasket cause overheating. It is a common thing across a lot of cars, but I've never personally heard of or witnessed it happen on KA's.

You can keep the radiator cap off while letting it warm up. But as it does all that will happen is the coolant will expand and start to flow out, or as what happened in your case, gush out rather violently. I personally fill up, fire it up, once it starts spilling out a little bit cap it off, get up to temp. Rev a couple times, shut her down, let her cool, pull cap off and top off if necessary.

First thing you need to realize though, is it isn't an "overflow" bottle. It's called a coolant reservoir for a reason. If the coolant pressure is too high, it purges it over to there. If a vacuum is created because of a small coolant leak, as the engine cools it will pull coolant from it. Get a proper coolant res on there. It isn't crucial, but it is part of a properly working system.

Also, I see no mention of a fan shroud for the radiator fan. That is a possible culprit. Get a shroud, put on your shroud, or convert to electric.

Also, backflush the WHOLE system, and not just the rad. Pull off upper radiator hose. Attach hose, turn on the water. Thermostat must be out for this. And then run some actual cooling system flush. Cheapo zerex stuff will be fine. a blocked heater core could cause overheating.

Go from there. If you had a bad head gasket, either you'd have coolant in your oil, oil in your coolant, a loss of compression, or coolant or oil entering the combustion chamber, or oil/coolant dripping down the side of the block. I've run the KA ragged into the red, and it's headgasket is fine. Not recommended, but myself, my friends, and even David B on here as admitted to beating the piss outta the KA while overheating with no ill effects.

One thing left to mention. Is it overheating while moving, instead of sitting still? Because if you took it out and drove it at 35 steady and it still overheats. It's a flow problem. If it doesn't overheat while moving, it's a radiator fan/air flow problem.

With the radiator cap off, do you get little geyser's out of the top?  If you do, that's compression from the cylinder getting in to the cooling system, and with the cap off, that's where the pressure goes!

Sounds like you top off coolant the same way I do, it takes about 30-45 minutes to get ALL of the air bubbles out.  I get the nose higher than the rear, ramps sometimes, or just an incline.  take the cap off, run the motor, and keep filling til it won't take anymore.  then I usually over fill the overflow for good measure.

Jay on 07:31:27 PM / 14-May-12a blocked heater core could cause overheating.

+1 on everything Jay said. As a side note, I like to run mine without the rad cap for a few minutes, watching for that bubbling and gurgling to indicate the thermostat is open and the air bubbles are getting out of the system. Yes, stuff will start to splash out a bit here and there, but I just keep topping it off until the car gets warmed up.

If you just slap the cap back on as soon as the thermostat opens, chances are you aren't getting all that air out.

Jay on 07:31:27 PM / 14-May-12I've never heard or seen of a KA having a bad head gasket cause overheating. It is a common thing across a lot of cars, but I've never personally heard of or witnessed it happen on KA's.

Jay on 07:31:27 PM / 14-May-12Go from there. If you had a bad head gasket, either you'd have coolant in your oil, oil in your coolant, a loss of compression, or coolant or oil entering the combustion chamber, or oil/coolant dripping down the side of the block. I've run the KA ragged into the red, and it's headgasket is fine. Not recommended, but myself, my friends, and even David B on here as admitted to beating the piss outta the KA while overheating with no ill effects.

One thing left to mention. Is it overheating while moving, instead of sitting still? Because if you took it out and drove it at 35 steady and it still overheats. It's a flow problem. If it doesn't overheat while moving, it's a radiator fan/air flow problem.

StephenG on 07:41:31 PM / 14-May-12+1 on everything Jay said. As a side note, I like to run mine without the rad cap for a few minutes, watching for that bubbling and gurgling to indicate the thermostat is open and the air bubbles are getting out of the system. Yes, stuff will start to splash out a bit here and there, but I just keep topping it off until the car gets warmed up.

If you just slap the cap back on as soon as the thermostat opens, chances are you aren't getting all that air out.

I have a '95 KA24DE in my S12, and I had this problem. After checking a bunch of things, I finally replaced the water pump and that solved the issue.

Arro on 09:44:27 PM / 14-May-12I have a '95 KA24DE in my S12, and I had this problem. After checking a bunch of things, I finally replaced the water pump and that solved the issue.

My ka had the same issue. Hot upper/cold lower. Your thermostat is not
opening as it should. Replace it with a nissan one and i bet your golden.
i had a cheap autozone t-stat and it was brand new. Switched to an oem
t-stat and its perfect.

Don't know if problem solved yet, but was thinking about it - try removing your thermostat and see if it runs cool - that's a quick & easy way to diagnose a thermostat problem.