Coolant flush turned brown (bad head gasket?)

[Pr86yota]

I am trying to revive my 86. I finally got it to a point where I can start the engine, so I went to try and flush the cooling system. Here’s the problem, I put 4 gallons of distilled water and a coolant flush bottle. Ran the engine for a few minutes ( high rpm’s maybe 1500 bc I am trying to tune my carb at the same time). Check the radiator and the water is brown overfilling out the funnel. I was an idiot and let it continue for maybe another minute. Did I blow my head gasket or is this common for an old cooling system and just had air in it?

I plan on getting a test kit.

 

[FJ Silver]

Doesn't look bad to me.
It is normal for the coolant to be brown when flushing, especially if you use flush chemicals and if the car has been sitting for a while. I can be brown for like 4 flushes.
I'd flush another time or two with distilled if you can, fill her up with your preferred coolant and run it. If you're really concerned, drain your oil, check for coolant residue there.
It takes a lot of heat for an extended period of time to blow a head gasket unless one of the cylinder has some major issue. Even with no water in the cooling system you should be able to run it for at least 5-15 min. My 2 pennies.

 

[Spook50]

That color is pretty well expected, BUT, it sure looks to have an oily consistency to it. I would go ahead and drain both radiator and block, verify that the oil on the dipstick looks fine and no milky buildup on the underside of the 710 cap, then do another flush to see if it looks better.

 

[Pr86yota]

@Spook50 @FJ Silver thank you for your replies. I checked the oil cap and dipstick and it looked clear, didn’t see any milky coolant mixture.

Checked the bucket of drained water, it’s definitely brown and dirty, but I didn’t see a oil sheen.

Refilled with distilled water and bought a radiator combustion gas kit. I was finally able to get my truck to run for a few minutes and tried that test 3 seperate times and it came back negative, as it supposedly didn’t detect any combustion gases.

However, it looks like it’s still bubbling up almost immediately.. do you think that’s a sign of a head gasket issue or just overheating very quickly. (New water pump has been installed btw)

 

[FJ Silver]

Can you expand on that last sentence?

" However, it looks like it’s still bubbling up almost immediately.. do you think that’s a sign of a head gasket issue or just overheating very quickly. (New water pump has been installed btw) "

So you refilled it with fresh water.
And as soon as you start the car, its bubbling from the filler neck? Bubbling is normal after all the flushing and air being trapped in there. The goal is to burp it long enough for all the air to get out.
It would be weird for after all that flushing the water to still be brown.
I'd stick a garden hose in there, open the engine water drain and let it flush for a while. Then close it up, flush with distilled one more time.

 

[Pr86yota]

Can you expand on that last sentence?

" However, it looks like it’s still bubbling up almost immediately.. do you think that’s a sign of a head gasket issue or just overheating very quickly. (New water pump has been installed btw) "

So you refilled it with fresh water.
And as soon as you start the car, its bubbling from the filler neck? Bubbling is normal after all the flushing and air being trapped in there. The goal is to burp it long enough for all the air to get out.
It would be weird for after all that flushing the water to still be brown.
I'd stick a garden hose in there, open the engine water drain and let it flush for a while. Then close it up, flush with distilled one more time.

I think something else I should mention, my temp gauge isn’t working. So technically I don’t know that it is overheating. I re-spliced the wire, but the gauge still isn’t reading anything.

To further explain, it is bubbling up after a minute of running- which could very well be air working its way out of the system. But it started bubbling up out of the radiator neck, which made me think it was overheating.

I will drain this water and refill with more distilled, also I need to buy a mechanical temp sensor

 

[FJ Silver]

I really doubt you messed anything up. Its hard to, when you're only running the engine for minutes at the time.

- I would recommend doing like a garden hose flush since its still so brown.
- Open up the engine block drain all the way, take out the thermostat, let it flush until the water out of the block is clear.
- Close your engine drain, fill her up with "normal" water. Bring the car up to operating temperature, Turn the heater to hot in the front and back and let it run for a while.
- Drain, refill with distilled, back to operating temp, heaters back on and drain.

Its normal for there to be a lot of bubbling. I squeeze the upper and lower radiator hoses quite a bit to help speed up the burping process. Its really helpful to have one of those burping funnels that fit on the radiator filler neck.
I often park it on an incline so the filler neck is the highest point in the engine bay when its time to burp.

The color of the draining water will tell you where you're at and how long you need to keep doing this.
But think along above lines, the priority is to get clean water from your drain. The water temp. gauge is pretty important, I'd replace that
In the meantime, I'd buy a cheap IR temperature gauge so you know roughly where you're at with temps.

Just keep in mind you have the radiator part of the cooling system, the engine block and the heater cores part to flush. The whole system takes something like 4 Gallons of water/coolant.

 

[Pr86yota]

I really doubt you messed anything up. Its hard to, when you're only running the engine for minutes at the time.

- I would recommend doing like a garden hose flush since its still so brown.
- Open up the engine block drain all the way, take out the thermostat, let it flush until the water out of the block is clear.
- Close your engine drain, fill her up with "normal" water. Bring the car up to operating temperature, Turn the heater to hot in the front and back and let it run for a while.
- Drain, refill with distilled, back to operating temp, heaters back on and drain.

Its normal for there to be a lot of bubbling. I squeeze the upper and lower radiator hoses quite a bit to help speed up the burping process. Its really helpful to have one of those burping funnels that fit on the radiator filler neck.
I often park it on an incline so the filler neck is the highest point in the engine bay when its time to burp.

The color of the draining water will tell you where you're at and how long you need to keep doing this.
But think along above lines, the priority is to get clean water from your drain. The water temp. gauge is pretty important, I'd replace that
In the meantime, I'd buy a cheap IR temperature gauge so you know roughly where you're at with temps.

Just keep in mind you have the radiator part of the cooling system, the engine block and the heater cores part to flush. The whole system takes something like 4 Gallons of water/coolant.

Thank you, this is very helpful- I don’t have my heater on, big mistake (but it’s the last thing I’m thinking about in my 100 degree garage). I’ll see what this drain out looks like and yes, I may need to switch back to hose water and then once it’s clear switch back to distilled. Temp sensor fix asap!

 

[Skniper]

Good advice above, That shot of the rad. filler neck doesn't look bubbly, it looks frothy/foamy. Is that the flushing agent or did someone put stop leak crap in it at some point?

I would also open the radiator petcock valve and dump a bunch of fresh water into the radiator and let it run clean with a passive flush, with out it running. Also no need to rev the motor while doing all this, just let it idle, and run the heater(s) on Hot (fan speed doesn't matter, just need the valve all the way to Hot and the fan on to know its blowing warm air).

Plain water in the system will get rusty quickly and will always appear dirty...like leaving it in for a couple days. Once you get everything running clean drain it all and refill immediately with a good new coolant/water mix. The rust inhibitor in the coolant really does work.

 

[Pr86yota]

Good advice above, That shot of the rad. filler neck doesn't look bubbly, it looks frothy/foamy. Is that the flushing agent or did someone put stop leak crap in it at some point?

I would also open the radiator petcock valve and dump a bunch of fresh water into the radiator and let it run clean with a passive flush, with out it running. Also no need to rev the motor while doing all this, just let it idle, and run the heater(s) on Hot (fan speed doesn't matter, just need the valve all the way to Hot and the fan on to know its blowing warm air).

Plain water in the system will get rusty quickly and will always appear dirty...like leaving it in for a couple days. Once you get everything running clean drain it all and refill immediately with a good new coolant/water mix. The rust inhibitor in the coolant really does work.

All good info, yes I have radiator petcock and engine drain both open now.. still coming out brown. Biggest problem is I have intermittent starting issues and I can’t tune the carb to run under 1500 rpm’s, I’m sure I have tons of other issues going on (I’m bringing this car back to life out of the bushes). So while trying to flush it I can only run it for a few mins at a time before it dies. Either way, plan is to keep flushing until it turns clear. I am going to start a new thread for my intermittent start/high rpm’s problem

 

[FJ Silver]

I wouldn't run the engine while flushing like this @Pr86yota
The garden hose method, do without running the engine. Just open the petcock, engine drain, let it flush.
When draining clean water, then close it all up, fill it up and run so you can flush the heater cores.

 

[Pr86yota]

I wouldn't run the engine while flushing like this @Pr86yota
The garden hose method, do without running the engine. Just open the petcock, engine drain, let it flush.
When draining clean water, then close it all up, fill it up and run so you can flush the heater cores.

Okay update now that I’ve had some time to run it. Ran a garden hose until water was clean, put 3.5 gallons of distilled in it. Ran the engine again and drained the distilled… still brown? I wasn’t able to do the exhaust gas bc water was bubbling out of the radiator, but it didn’t seem like it was boiling, running hot or overheating. I installed a temp gauge (I don’t know how accurate it is) but it didn’t go above halfway. I’m so confused, do I have a really dirty cooling system/block or is the head gasket blown

 

[Spook50]

Okay update now that I’ve had some time to run it. Ran a garden hose until water was clean, put 3.5 gallons of distilled in it. Ran the engine again and drained the distilled… still brown? I wasn’t able to do the exhaust gas bc water was bubbling out of the radiator, but it didn’t seem like it was boiling, running hot or overheating. I installed a temp gauge (I don’t know how accurate it is) but it didn’t go above halfway. I’m so confused, do I have a really dirty cooling system/block or is the head gasket blown

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I say if you don't see any oil sheen on it, keep on flushing cause it's dirty as sin!

 

[FJ Silver]

Keep in mind that when you fill the system and start the engine, its going to circulate, perhaps get water from the heater core, the thermostat will open etc.
I'd flush a few times with regular water like you did just now. Drain from engine and the radiator drain. Fill up, run the engine until hot, turn heater on.
Drain and repeat until clear.
Something in there is pretty rusty most likely creating that brown water. Again, if you're really worried, drain some oil in a clear container. I really doubt you'll see any signs of water in there. Look up picture of oil and water in Google.