I know this is a Corolla forum, but you guys have the K motors

 

Just replaced the water pump and hoses on my 5K.  This engine has a radiator cap on the water neck, owing to the position of the radiator in the KM30.  Today while running the engine with the cap removed, I observed at higher RPMs that water churns right out the top.  Is this normal behavior?  I had expected sort of an 'upwelling' of water coming up out of the head to the water neck and rad hose.  But this shoots out with enough force that it is also going out my overflow hose, which attaches in the same location as the top rad hose.  This explains why I lose about a liter of water over the course of a 20 minute highway drive, and also why poking around town it won't really lose much water at all (no overflow bottle, long story).  

I do not believe there is any thermostat installed, tomorrow I will pull the t-stat housing and have a look.  It occurs to me perhaps the t-stat normally would prevent the churning that I'm seeing.  

 

Any thoughts?

 

Edited July 31, 20197 yr by Papay
updated pic

Yep, I'd expect you are right.

..and seeing there is no trace of coolant stains there I'd say you live in a hot climate and the previous owner had some sort of cooling problem with it.

Confirmed no t-stat installed.  Spent the better part of the afternoon with my father in law making a bracket to hang the overflow bottle, Philippine style.  Yes you are correct, no coolant until I can keep everything in the system haha.  After installing and filling the overflow bottle, we took it for an extended drive with no issues.  Today was cooler, however, but tomorrow is a trip over the mountain.  Fingers crossed.....

My theory is the weight of the water in the bottle would serve to prevent casual splashing at the neck from getting through the overflow tube -- it has a volume of water pushing back against it.  Will keep an eye on things and plan to install a thermostat.  

Would like to find a 'natural' coolant if anyone has any suggestions.  Not that I am against paying for coolant, but many times where I live things are not as available as I would like them to be.  The block was surprisingly clean when I had the water pump off, after running straight water for who knows how long.  

I haven't come across any natural replacements. The usual formulations are ethylene glycol to control the freezing/boiling points and nitrite to stop rust. The new coolants replace nitrite with an organic acid that they reckon does the same anti-corrosive job but lasts longer. The sodium nitrite attacks some aluminium welding in some new cars, hence the specs for 'pink' coolant. Most cars never hit 100deg C so never use the properties of the glycol. The t'stat opens around 78deg and the motor sits around 85-90deg.

See how you go with it not boiling. Tridon have high-flow thermostats if that helps, or the final solution would be a Chinese aluminium radiator.

I already put in a brand new Evercool 3-row radiator (not sure where made).  It runs cool as a stone around town, so I think the thermal capability is pretty good overall.

Two observations made since yesterday which concern me:  1) a kind of milky slime in the t-stat housing, 2) white smoke from the exhaust at higher rpms.   So I'm thinking a new head gasket may be in store.  

Not good....  Well, don't worry about coolant,that's for sure!  When you get a t'stat in it, fill it up and start it from cold with the rad cap off.  Any compression leak usually pushes bubbles up the radiator and floods half a litre of water out before the bubbles can escape. Maybe this is why there was no t'stat in there. I'm not sure how well this test will work with your rad cap placement, but give it a go.  Also, it loses that top bit of water then doesn't lose the rest so quickly, day after day if you top it up.

You can pull the plugs out before starting it one day and see if one or two have moisture on.

Forward-control trucks & vans....  horrible to work on!

Well, trip over the mountain yesterday was uneventful.  Temps never even reached the half-way mark, through some fairly steep climbs.  After we reached our destination, we stopped for a bit so I decided to check the water level.  Overflow bottle still full, but the radiator was down about half a liter from where we started.  So yeah, I'm suspecting a bad head gasket at this point.  

Now I'm thinking the kind of 'chuffly' sound this van makes is not just a leaky exhaust, its probably the head gasket.  At least nothing is getting into the oil.  

Gotta say, for a 25 year old pushrod engine, this little lump amazes me.  It runs incredibly smooth, oil stays really clean, no tapping noises or slop, etc.  

That's good enough for a while!

Get hold of a thermometer that goes to 110deg or more (so not a medical one, maybe an infra-red gun), check it against boiling water and then check it in the rad while it idles up to running temp. Don't trust the gauge unless you've checked it. Take look through here, we had the classic 4K chuff from a blown manifold gasket, and a one-piece gasket plus checking all the holes and bolts solved it forever.  Just looking at that front manifold bolt of yours....

https://www.rollaclub.com/board/topic/42407-the-girls-ke70/?_fromLogin=1

Hi Scott,

              Spark plug moisture test, & a compression test, when engine is hot, should be able to determine whether the head gasket has blown.  Colour comparison of spark plugs can also be a good indicator, if one or two, have internal insulators, that are lighter than the others.

Don't forget to check all the whelsh plugs, especially the one at the back of the head.  They can almost rust through, & dribble ever so slightly, losing say 1/2 litre on a trip. Sometimes hard to detect, as when the water dribbles out, it runs over a hot block & evaporates.  I have seen this occurrence more than once, on old Rolla engines.

Cheers Banjo

Speaking of which, we just had the plugs out and cleaned them over the weekend.  Everything looked good there, but at the time I wasn't looking specifically for signs.  The Welsh plugs are a good thought, I remember reading about issues with those in other threads.  Here are the part numbers I have on my "may need to order this" list:

96412-01800 front freeze plug (sm)

96411-43500 side freeze plugs (3)

96432-23814 rear freeze plug (#1, lg)

96411-44500 rear freeze plug (#2 ,lg)

I remember as a kid helping my Dad work on his Mopars, and we always replaced the steel plugs with brass ones to prevent future rust.  Is this an option with Toyotas?