Coolant blow out:"(

Nic · Jan 12, 2015

I was driving to school this morning, and as soon as I pulled into the parking lot, my truck started pouring smoke. I shut it off in a hurry and popped the hood, and the smoke was comming from drivers side rear engine. It had coolant when I left this morning, but all of it was gone. Now, when I put water in the radiator, it just pours out the back of the engine. Freeze plug? Some sort of hose? It was running fine when I pulled in, before it started smoking...so I hope it's still ok. And I know what ya'll are thinking, shouldn't the temp gauge have been a warning, well that's broke and on my to do list to fix. Please help!

enjr44 · Jan 12, 2015

You are going to have to tell us where the coolant is going. Was it smoke or was it steam from leaking coolant? Temperature gauge not working is asking for a melt down, just saying.

RonD · Jan 12, 2015

What engine do you have?
4cyl, 3.0l, 4.0l

Yes, more than likely a Core plug(freeze plug) has rusted thru and come out, although I think the 4cyl has a hose that runs around the back side of engine to the intake.
They can safely be replaced with rubber expansion plugs.

Just FYI, these are not there for possible freezing.

Nic · Jan 12, 2015

Sorry, it's the 4.0. Yea, I know, it's been on the to do list, and now it's on the necessary list. It's pouring out the back of the engine, drivers side.

AllanD · Jan 12, 2015

On the 4.0 there re core plugs in the ends of the cylinder heads as well as in the back of the block (under the flywheel all are an absolute BASTARD to access with the engine or trans in the chassis...

Good luck.

My "Boggle" at the moment is discovering my passenger side motor mount is "Fooked"
which allows my 4.0 to sit low on that side resulting in the cat flange of the Y-pipe to hit the lower flange of the frame before I can get the trans tailshaft to move enough to the passenger side to allow me to get the tranny mount studs to drop into the holes in the cross-member.

I hope your problem isn't an engine fatality, I keep TWO spare 4.0's on hand to deal with that possibility.

I've never had a lot of money, so I need to be ruthlessly methodical to plan for "Mechanical Disasters" that inevitably occour...

MY having parts on hand has saved the bacon of an awful lot of people who don't have the storage space to keep spares...

I can't even recall the guys who were 4wheeling across the country for an article for some 4x4 magazine and U-boated their 4.0 Bronco2 and needed an engine (Can't fix bent rods)
when Jim called me and asked if I had an engine for them... Yep I did On 2hours notice I had it out where they could get it they showed up and away they went..

The funny part Is I had another engine from the junkyard (that I saw running before they pulled it for me) hours before they had the engine they got from me into their B2

I have one regret... they were putting it in a B2 with an Auto Trans, and I forgot to pull the clutch and flywheel off of it before the engine left, which caused me trouble later...

adsm08 · Jan 12, 2015

Temp gauge might not have told you anything useful anyway. Those older ones would read low temp if the coolant was low. They aren't designed to read air temps, only water temps.

Anyway, sounds like you lost a plug. I gotta say though, "back of the engine" isn't really specific enough.

Nic · Jan 12, 2015

AllanD said:
On the 4.0 there re core plugs in the ends of the cylinder heads as well as in the back of the block (under the flywheel all are an absolute BASTARD to access with the engine or trans in the chassis...

Good luck.

My "Boggle" at the moment is discovering my passenger side motor mount is "Fooked"
which allows my 4.0 to sit low on that side resulting in the cat flange of the Y-pipe to hit the lower flange of the frame before I can get the trans tailshaft to move enough to the passenger side to allow me to get the tranny mount studs to drop into the holes in the cross-member.

I hope your problem isn't an engine fatality, I keep TWO spare 4.0's on hand to deal with that possibility.

I've never had a lot of money, so I need to be ruthlessly methodical to plan for "Mechanical Disasters" that inevitably occour...

MY having parts on hand has saved the bacon of an awful lot of people who don't have the storage space to keep spares...

I can't even recall the guys who were 4wheeling across the country for an article for some 4x4 magazine and U-boated their 4.0 Bronco2 and needed an engine (Can't fix bent rods)
when Jim called me and asked if I had an engine for them... Yep I did On 2hours notice I had it out where they could get it they showed up and away they went..

The funny part Is I had another engine from the junkyard (that I saw running before they pulled it for me) hours before they had the engine they got from me into their B2

I have one regret... they were putting it in a B2 with an Auto Trans, and I forgot to pull the clutch and flywheel off of it before the engine left, which caused me trouble later...

Well thank you for the advice and the laugh! It is the freeze plugs, so I'd replace the little things myself, except I can't get to them. Had it towed to the shop, 165 in labor :"(. Stupid truck. Thank God, the head gasket seems ok, but if it's not can I please have one of those 4.0's

...just kidding

Nic · Jan 12, 2015

adsm08 said:
Temp gauge might not have told you anything useful anyway. Those older ones would read low temp if the coolant was low. They aren't designed to read air temps, only water temps.

Anyway, sounds like you lost a plug. I gotta say though, "back of the engine" isn't really specific enough.

I didn't exactly have mirrors or anything to pin point the location where it was comming from at school...but when I had tools delivered it was plain to see that my freeze plugs were gone. We'd put water in the radiator and it would come pouring out that hole

RonD · Jan 12, 2015

If it is a 4.0l OHV you probably have a cracked head or two.
They don't overheat well at all, weak point in the casting between valve seats.

If it is at a shop ask them how much to do a cooling system pressure test, should only be a few dollars.
Have system filled and then have them crank the engine(coil unplugged) with pressure gauge still on rad cap opening.
If pressure gauge starts to bounce up and down you have a cracked head.

Nic · Jan 12, 2015

Well that's not very good sounding. Ok, I'll have them check for that, thanks

AllanD · Jan 20, 2015

The "Core plugs" are there to extract the sand forms used in the casting process from the cooling jacket part of the block.

The "Freeze out" name is more of a description of what they DO rather than what they are for... if you run insufficient anti-freeze and the water in the block freezes the expanding water pushes them out of the block....

After that obviously the coolant all leaks out of the block

Coolant blow out:"(

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