Boiling coolant

[jmvb]

Hi guys

My 98' XLT comes without Tstat, so, the truck take a long time to warm

It found a OEM Tstat, and it put it. Now, the truck warm fast, and the gauge stay right in the middle.

Few weeks ago, I saw coolant residues in the plastic tank.
Later, after a 100K trip, I heard a pressure air leak in the radiator cap area, and the water in the tank was boiling
I did change the hose zip. The air leak and the boiling remain
I did change the radiator cap, because it isn't a right one (only 15psi), and I had to add 4 lt of coolant.
I continue see coolant residues in the plastic tank cap (it is 1/4 fulll), and no more air leak, but I'm not sure about the boiling, because I'm only had drive into the city relative short distances, no long highway travels.

It is normal?

 

[alohamonte]

Boiling coolant is not normal.

 

[jmvb]

After those improvements, I have not see the boiling again, but still seeing coolant residues in the plastic tank.

Are these residues normal?

(But I'm not sure if the boiling happens and cause the coolant residues
or if it will happen in a highway trip)

 

[MillerAPF97XLT]

There should be a minimum or "full cold" level and a maximum or "full hot" marked on the recovery tank. The minimum keeps the system from sucking air in as it cools when you shut the engine off. Way over the maximum could be interpreted as an overheating problem. Look closely at all visible sides of the tank; you should see markings SOMEWHERE on it.
Having said all that, on my '97 with the 4.0 SOHC, the only mark is the cold, and it's at the front, towards the fender. Still, if your '98 is the same, I would start there. Might not hurt, also, to check the strength of your coolant mixture - too weak a mixture will boil at a lower temperature than a 50/50 mixture. You may have solved your problem with the new cap, though. Take it on a long enough trip to warm it up good, shut it off and take a look. Let us know what you find. Chris:exp:

 

[Robman]

I would imagine if you were low on coolant and you ended up adding 4 liters to it, it got hot and the air in the system expanded, opening the rad cap and bubbling in the expansion tank.

Or... bubbling coolant is a headgasket issue.

Residue? Unless it looks fresh and not accumulated over time, I wouldn't worry a whole lot about it.
If your system is fine, it may be worth giving it a flush and cleaning the residue out of the tank.

 

[Turdle]

You should try to remove the residues from the reservoir.

Hot radiator pressure may vent coolant into the reservoir, which should flow back to the radiator when it cools. The residue will settle to the bottom and clog the hose connection, blocking the return flow. Over time this may lead to excess venting and overheating, coolant loss.

I bet your original fill left an air pocket in the cooling system, and it was this air pocket which you heard bubbling in the reservoir. Try cleaning the reservoir and refill the coolant while parked at an uphill angle to help move the air pocket to the radiator cap. Fill, run to warm, allow to cool, then recheck fill level in the radiator. Always refill from the radiator cap.

 

[MillerAPF97XLT]

Good calls on air pocket and head gasket, Rob and Turdle. Head gasket would show up as a more-or-less constant bubbling, easily seen from the radiator cap neck, yes? Whereas a pocket would show as more of a "burp"? As for the residue - Is it the left-behind solids/sludge after the coolant evaporates, or is it the liquid that should be in the tank? If it's the solids, is it normal coolant color, or rusty colored? A lot of solid residue wouldn't be normal for a healthy cooling system in a daily (or frequent) driver. Some more information here would help us help, I think. Agreed that excessive build-up should be cleaned out, then I would think fill the radiator and tank to the correct cold levels, and drive to check. As always, just my $0.02; your mileage may vary. Keep us in the loop - Chris:exp:

Edit: After looking at one of jmvb's earlier posts, I'm given to believe the "residue" he's seeing is, indeed, the leftover solids. If he bought it used with no thermostat, sounds like he inherited a hot-running problem with the truck.

 

[jmvb]

[MENTION=298235]MillerAPF97XLT[/MENTION] found the mark

It say "cold fill", but nothing about "hot"
I made a mistake, I had the coolant level almost full the plastic tank...
It could be the cause of my problem? too much coolant in the reservoir?

With "coolant residues", I mean liquid residues, green coolant drops arround the plastic tank cap

Yesterday, I ran the engine in idle, with the radiator cap out, and I wait for warm. Heating on in hot.

The coolant level up the radiator exceeding a little bit.
About 15-20' later, I saw a few bubbles, and the level down (I guess that was the T-stat opening)

Ran 10' more, and nothing weird happens.
I did stop the engine, refill the radiator, and put the cap.

Should I take off the coolant in the tank up to the cold fill?

Thanks to all for post and help!

 

[MillerAPF97XLT]

Looks like you have the EXACT same tank as me. So your only reference is the cold mark. With the engine COLD, yes, I would siphon or drain the overflow tank down to your cold line. And make sure the hose going from the overflow tank to the radiator has a good, snug fit at both ends to reduce the possibility of introducing unwanted air BACK into your system through a loose fit. Once your system is completely full of coolant, you should only have to add some coolant occasionally to the tank. I'm still curious what a good, long test drive is going to show you. Let us know if you get the chance. - Chris:exp:

 

[jmvb]

Maybe i forgot to say, the boiling which I had, happened when I stopped the engine, after 100K trip (and I heard a pressure air leak in the radiator cap area)

 

[jmvb]

Maybe here is my fail?

I'm using this coolant (pick the translation tab at top)

http://www.lubristone.com/inicio/index.php/features/mantenimiento/refrigerante-verde

The instruction (which I just noticed) says 50% y 50% mix... and I add it pure, not mixed...

 

[Robman]

If you buy pure antifreeeze, you mix that 50/50 with distilled water.
If you live where the temps stay above freezing, there's no reason not to sway that ratio to having more water 60/40 .. 70/30, using just the anti-corrosion and lubrication properties of the fluid. That's my opinion anyway.

You can buy jugs that are already 50/50 mix however.
I don't personally find the expansion tank level to change too drastically when hot/cold whatever.

The actual antifreeze just keeps it from freezing and adds some waterpump lubricant, the water is what actually does the cooling.

You don't want to overfill the expansion tank simply because if/when the coolant "expands" it will seep out of the lid of the tank and overflow out onto the ground. Not really a huge deal although mother nature would take the hit.

It sounds like you made a few errors.. life is for learning

 

[MillerAPF97XLT]

Hey, jmvb. Seems like I remember you mentioned earlier in your thread about the trip and that you replaced the cap with one of the correct pressure rating. That's good - often we make things right a little at a time. And Robman's right - anybody who has never made a mistake just hasn't done enough. Guessing, based on the product you showed us, you're in South or Central America? If so, yeah, you wouldn't so much need anti-freeze as coolant, like the jug says. Let us know what's happening... Chris:exp:

 

[jmvb]

[MENTION=298235]MillerAPF97XLT[/MENTION]

Right! I'm in Chile! that's why my english is weird!

The weather in my place is about 23ºf in winter and 95ºf in summer


Should I mix 50% of coolant and 50% water?

 

[MillerAPF97XLT]

Your English is fine - better than a lot of people living here! Hmm - as for how to mix your stuff, I think for simplicity's sake, I would use a product with coolant AND anti-freeze properties, since you do see temps below freezing, and mix it half-and-half if that's what it says gives you the best protection. The product you linked us to said it was not anti-freeze. Because of your location, something with both may be hard to find.

 

[jmvb]

Today, after to refill the A/C system, with nearly 95Fº, and drive 30min in light city traffic, I saw the RPM increase about to 1000...
I park and open trunk, and again, the coolant in the reservoir boiling..
The gauge is just in the middle.

Like I said before, I purge the cooling system, wait to the Tstat open, and only saw a couple of big bubbles (air I guess) and no more, keep the coolant in the reservoir just in the mark.
No exaust smeel in the coolant, no more bubbles, so I deduce that I haven't head gasket blow issues

Tstar new since 4 months ago, radiator cap motorcraft one, since 2 months

Any clue? (no mix jugs yet, only coolant)

 

[koda2000]

Today, after to refill the A/C system, with nearly 95Fº, and drive 30min in light city traffic, I saw the RPM increase about to 1000...
I park and open trunk, and again, the coolant in the reservoir boiling..
The gauge is just in the middle.

Like I said before, I purge the cooling system, wait to the Tstat open, and only saw a couple of big bubbles (air I guess) and no more, keep the coolant in the reservoir just in the mark.
No exaust smeel in the coolant, no more bubbles, so I deduce that I haven't head gasket blow issues

Tstar new since 4 months ago, radiator cap motorcraft one, since 2 months

Any clue? (no mix jugs yet, only coolant)

I'm chasing the exact same issue with a friend's 4.0L SOHC. I know for sure that it has a head gasket exhaust leak into the cooling system. It's not boiling, it's bubbling exhaust into the coolant reservoir. I'm even pretty sure I know which cylinder is leaking, from spark plug examination. When it's warmer out we plan to try a head gasket sealant, running the engine with the spark plug out and injector disconnected to allow the sealant to get into the break in the gasket. If this doesn't work his choice is to find a replacement engine or sell the truck for parts.

 

[jmvb]

I'm chasing the exact same issue with a friend's 4.0L SOHC. I know for sure that it has a head gasket exhaust leak into the cooling system. It's not boiling, it's bubbling exhaust into the coolant reservoir. I'm even pretty sure I know which cylinder is leaking, from spark plug examination. When it's warmer out we plan to try a head gasket sealant, running the engine with the spark plug out and injector disconnected to allow the sealant to get into the break in the gasket. If this doesn't work his choice is to find a replacement engine or sell the truck for parts.

It is not the same issue, because I know that is boiling and not bubbling exhaust into reservoir.

If I turn of the engine, the boiling remains into the reservoir for a while..
I have not loss of coolant in the system. The level is the same into the radiator and the reservoir, so far..

 

[jmvb]

bump!