Overheating and "Popping"

[Ranchero50]

Water should be fine while you are troubleshooting as long as it doesn't freeze solid.

You never did mention that the upper hose was getting hot.

Water is sucked from the lower radiator hose, through the pump to the block, then through ports in the back of the head gasket and back up through the head to the front intake passage, then through the T-stat and back to the radiator. The bypass between the water pump and the intake and the heater hose allow coolant to flow while the t-stat is closed.

If the upper hose is staying cool, then you have something blocking the flow through the radiator. If it is then you have too much heat getting to the coolant. Cracked block, thin cylinder walls or something else equally bad. That's why I asked if the hose was getting hot.

[Robbie]

All of the hoses(Upper, Lower and heater) seem to be of equal warm temperature. At least not of any significant difference to the touch.

[Ranchero50]

Interesting... I wonder if the small steam holes in the top of the head gaskets are plugged and you are hearing the steamed water popping?

How are you measuring the temp to determine an overheat?

[Robbie]

The following surface temps were taken using a hand held non-contact infrared heat gun.
Ambient temp of everything before starting was about 50 degrees F.
Vehicle was started and left to idle for about 9 minutes before "popping" noise started. At that time the following SURFACE temperature readings were taken. All readings below are degrees Fahrenheit.
Upper Radiator Hose-98
Lower Radiator Hose-98
Heater Hose-95
Heater Hose-99
Water pump to head on Drivers Side-145
Water pump to head on Passengers Side-110
Intake Manifold on Drivers Side-180
Intake Manifold on Passengers Side-130

After running for about 16 Minutes and popping noise continuing to get worse-
Upper Radiator Hose-100
Lower Radiator Hose-100
Heater Hose-102
Heater Hose-110
Water pump to head on Drivers Side-185
Water pump to head on Passengers Side-113
Intake Manifold on Drivers Side-200
Intake Manifold on Passengers Side-135

After running for about 20 Minutes and popping noise continuing to get worse-
Upper Radiator Hose-108
Lower Radiator Hose-108
Heater Hose-104
Heater Hose-114
Water pump to head on Drivers Side-200
Water pump to head on Passengers Side-140
Intake Manifold on Drivers Side-200
Intake Manifold on Passengers Side-140

After I turned off the engine the "popping" noise continued for about 2 minutes. At this time I was able to release the pressure on the radiator cap and restart the engine and observe the rusty water(Still with coolant flush) flowing through the radiator. I was able to check the water temp, through the open radiator, and it was at 120 and the "popping noise" was heard again at that time.

Additional Notes-
It seems to be taking a little longer for the popping noise to start than before. It is now 9 minutes compared to the previous 7-8 minutes. Hopefully this is because the flush chemical is clearing out what ever is clogged and not just that the ambient temperature is cooler now. Also the temperature gauge in the truck is no longer going beyond 1/2.

[Ranchero50]

OK, from those readings my gut feeling makes me think the all of the head gasket ports have 'grown' shut from the oily coolant solidifying over time (that's the oatmeal looking stuff). See if you can crimp off the water pump bypass and the heater hose and still get water flow through at the radiator with the cap off. I think your only pumping radiator coolant through those passages and not through the engine itself.

Remedy is to pull the heads and replace the gaskets. Not a terrible job, but the intake is heavy and so are the heads if you leave the exhaust manifolds bolted to it (recommend that to avoid broken bolts).

[tnlprt]

Just pull the head and see if you have a problem ...

No need to pull the intake on the FE engine just to pull 1 head

[rwilly]

I am thinking the coolant isn't flowing throughout the engine/radiator.
The hose temps are too low (100*).
There is a block in the system somewhere.


You hook a garden hose up to a port on the heater hose, where is the dirty water expelled from?

It has been awhile since I have done the procedure.

[Robbie]

When the water hose is connected to the "Flush T" on the heater hose and turned on, the dirty water is expelled through the open radiator cap and the drain on the bottom of the radiator.

[Ranchero50]

When the water hose is connected to the "Flush T" on the heater hose and turned on, the dirty water is expelled through the open radiator cap and the drain on the bottom of the radiator.

That's not really answering the question. It will flow that way but I suspect it's going through the intake to the bypass hose, through the water pump and then to the radiator not through the block like you want it to. Without the Tstat in place it's also flowing through the top radiator hose. Your radiator temp readings are way too low vs. the temps at the heads and intake. They should be consistent and you should notice a difference between the top and radiator hose as the radiator exchanges the heat to the air around it. Typically you can feel the individual tubes and find blockages by the ones that are cooler than others.

Basically I think what you are hearing is the coolant boiling off around the cylinder walls because it can't flow through the head gasket. I had a similar problem on a 4.0l in the wife's Explorer when the Tstat stuck closed. It gurgled and made popping sounds deep in the engine and puked air / water out the radiator cap.

At this point I'd pull the heads. I don't think there's anything else to be gained by trying to flush it unless you want to go with a straight vinegar soak. Again, the crap that breaks free is going to end up clogging the radiator back up...

[Busboy]

I've only seen it happen one time in 35 years and that was on an international engine. The water pump impeller came loose from the shaft. No circulation of course. You might be able to look in through the lower hose connection instead of having to pull the pump off.

[Robbie]

Impeller on water pump in intact.

I fear I may be pulling the head/heads. Over the past few days the vehicle has become increasing difficult to start and is now missing and backfires when it first starts up. I think if the water jackets in the heads are as clogged as suspected, I may have blown a head gasket at this point. This will probably turn in to a "Project Creep" now.....

When I pull the heads to do a head gasket, might as well have the heads done at the same time, since this is the original engine (145,000 miles) and nothing major has ever been done to it. With that said, I suppose it may probably be just about time for a complete rebuild if I am going to that much trouble?

If I have to pull the engine anyways, maybe I should look at installing a good running 460 I have readily available that only has 80,000 miles on it? Any ideas if the 460 will drop right in where the 360 was? The truck has a 4 speed (Compound low with 3 additional forward gears and 1 reverse gear)manual transmission, which I would like to retain if possible. The 460 is a 1973 that is currently in a 1977 Lincoln.

See how this project begins to creep. Any suggestions?

[BobbyFord]

I would pop out a couple of the easiest block freeze plugs out and take a peek inside. It sounds like someone had a prior overheating problem and put a bunch of stop leak in it. I hate stop leak.

[Robbie]

Conclusion/Followup-
In the end, it was as one person had suggested. The water jackets in the head had rusted nearly shut and eventually blew the head gasket. I took it down to a local shop and they replaced the head gaskets and did a valve job. Truck runs great now. Thanks to everyone for all of their help and input.

[cameronscraig323]

I had this exact problem and thanks to this forum and the Evaporust solution, my engine is running perfectly. I am so thankful for this forum

1969 F250 which had been siting for a number of years. I had it rewired, then I switched it to a Holley Sniper fuel injection. I flushed radiator, changed oil, pumped out fuel, changed filters etc. and after some messing around I got it running.

But after two minutes, the popping sounds started. I could not get rid of it. More radiator flushing (3 times!) and no change.

AND, the pops stayed after the engine was switched off. Video available here of the actual sounds.

https://youtu.be/P473qVQqdPo

I followed the suggestions on this forum to use Evaporust to flush out the water jackets as I had nothing to lose and a rebuild was going to be very expensive. I dumped the radiator contents, removed the thermostat, filled the entire system with evaporust. I found some evaporust that was designed for cooling systems so I had a mix of 50% of that blend and 50% regular evaporust. Over $150 in evaporust. The thermostat was covered in a bit of rusty looking goo so I used that as a control and filled a glass jar with evaporust and dropped the thermostat in so I could observe what the evaporust would do.

I started the engine twice a day and ran for two minutes to keep the evaporust moving around to different positions in the engine. I kept checking the thermostat -- the rusty build up on the thermostat just was just melting away slowly. I was amazed. And having no thermostat in the engine meant I was getting it all nicely circulated within the couple of minutes of start up.

Did this for 4 days. The popping sounds totally disappeared. The crud on thermostat had melted away. I took it for a small drive. It didn't even get it hot - 165 degrees. Did another small drive. Everything sounds amazing.

Dumped all the evaporust out -- it was black and dark and thick on the way out (gold color on the way in) but amazingly, it is all fluid - no chunks. The evaporust just liquifies it all.

After a full flush of the system, I replaced thermostat, reloaded with coolant, have been running strong for two months now. Highway driving, it runs like a dream. So grateful to this forum.

[Robbie]

Another thing I did not consider and found out the hard way. Even though the heads were rebuilt, there was still rust and crap in the block that I did not think about. This contamination ended breaking up and clogging my radiator several times. I installed a filter on the upper hose to catch the contaminates and all is good now but still have to clean out that filter periodically.