Head freeze plug turns into head gasket replacement (1 Viewer)

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Iceman here. Some of you may remember when I accidentally left distilled water in my truck at our first freeze. Well, fast forward and I put the new oil cooler on, new thermostat and housing, etc....

I went to fill it up with 50/50 Toyota red and distilled water. Got about two gallons in and it started pouring down from the transmission tunnel area. My initial thought wasone of the rear heater lines burst because I already had them rust through further down the line. Got Joey's bypass kit today, put it on and it still pours out the back. I visually confirmed it's not coming from any of the firewall connections.

I have never pulled one of these engines and my Chinese borescope isn't good enough to show me where the issue is. Anybody have a thought? I am hoping to mostly get it figured out to know if it's beyond my banana level before I get it towed somewhere. I'm a :banana::banana: to :banana::banana::banana: mechanic (but sometimes a dummy - see distilled water comment above).
 

flintknapper

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Iceman here. Some of you may remember when I accidentally left distilled water in my truck at our first freeze. Well, fast forward and I put the new oil cooler on, new thermostat and housing, etc....

I went to fill it up with 50/50 Toyota red and distilled water. Got about two gallons in and it started pouring down from the transmission tunnel area. My initial thought wasone of the rear heater lines burst because I already had them rust through further down the line. Got Joey's bypass kit today, put it on and it still pours out the back. I visually confirmed it's not coming from any of the firewall connections.

I have never pulled one of these engines and my Chinese borescope isn't good enough to show me where the issue is. Anybody have a thought? I am hoping to mostly get it figured out to know if it's beyond my banana level before I get it towed somewhere. I'm a :banana::banana: to :banana::banana::banana: mechanic (but sometimes a dummy - see distilled water comment above).

Put a pressure tester on your radiator and then use your borescope to locate the leak. You might be able to see back there with just a good flashlight.
 
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Put a pressure tester on your radiator and then use your borescope to locate the leak. You might be able to see back there with just a good flashlight.

I had the wife pour in distilled water and looked to find the outlet - definitely the area of the rear heater lines but couldn't find the source. I'll dig out a brighter light and see what I can find.
 
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Freeze plug in back of head is probably leaking or out. You will have to pull the head to repair. Get a mirror and look between the head and fire wall there while some fills with coolant
 

flintknapper

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I had the wife pour in distilled water and looked to find the outlet - definitely the area of the rear heater lines but couldn't find the source. I'll dig out a brighter light and see what I can find.

Sounds like you're on it. And be sure to thank your Wife.

Mine would never chance getting her hands dirty or 'breaking a nail' to help out with car repairs. ;)
 
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Thanks - I was thinking freeze plug but have never had one go. The engine is in great shape so I was hoping I wouldn't have to completely pull it and get it machined, etc....

I can probably handle pulling the head. I just recently did the valve cover gasket, removed and cleaned the TB and intake manifold along with the TB coolant hose and the PHH. I reckon the head isn't probably too much beyond that.

And definitely thanking the wife
 
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2nd question - can you reach and repair the freeze plug without pulling the head? Maybe drop/tilt the engine/transmission assembly?
 

flintknapper

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2nd question - can you reach and repair the freeze plug without pulling the head? Maybe drop/tilt the engine/transmission assembly?

No. As stated above, no way to access without pulling the head.
Well......or the whole body, but we don't want to do that. ;)

freeze plug head.JPG
 
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bencallaway

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Thanks - I was thinking freeze plug but have never had one go. The engine is in great shape so I was hoping I wouldn't have to completely pull it and get it machined, etc....

I can probably handle pulling the head. I just recently did the valve cover gasket, removed and cleaned the TB and intake manifold along with the TB coolant hose and the PHH. I reckon the head isn't probably too much beyond that.

And definitely thanking the wife
Pulling the head will be a breeze if you just did all that stuff. Follow the FSM for cam removal.
 

flintknapper

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Thanks. I'll plan on pulling the head this weekend. Thankfully most of the while you're in there items around it are done.
You might use a flashlight and inspection mirror to 'confirm' a leak from back there before pulling the head. There are other reasons you might have a coolant leak in that general area.

Hope you get it sorted out....I know this has been a trying event for you.
 
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You might use a flashlight and inspection mirror to 'confirm' a leak from back there before pulling the head. There are other reasons you might have a coolant leak in that general area.

Hope you get it sorted out....I know this has been a trying event for you.
I could barely see the edge of the lower plug and it appears that's where the leak is. I will confirm with a mirror, better light and a helper tomorrow. What other things could leak there? I can confirm it's not rear heater lines, heater valve, or the two firewall coolant lines.

Thanks, it has been trying. Especially after such a stupid mistake.
 

flintknapper

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I could barely see the edge of the lower plug and it appears that's where the leak is. I will confirm with a mirror, better light and a helper tomorrow. What other things could leak there? I can confirm it's not rear heater lines, heater valve, or the two firewall coolant lines.

Thanks, it has been trying. Especially after such a stupid mistake.

You've covered most them then. The PHH and coolant line off the head that goes up to the throttle body are back in that area (drivers side under the intake) and if either had a pin hole or split....could spray coolant back toward the firewall. But sounds like you've found the problem already.
 
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You've covered most them then. The PHH and coolant line off the head that goes up to the throttle body are back in that area (drivers side under the intake) and if either had a pin hole or split....could spray coolant back toward the firewall. But sounds like you've found the problem already.

I just replaced both of those as well, when I took the manifold off. Also did vacuum hoses, fuel filter and it feels like a million other things. Almost all the hardware is new, so should be easier to take off components this time.
 

bencallaway

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I just replaced both of those as well, when I took the manifold off. Also did vacuum hoses, fuel filter and it feels like a million other things. Almost all the hardware is new, so should be easier to take off components this time.
At least you didn’t do the hg then too. Get a valve job and deck it.
 

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