so I have been smelling antifreeze in the cab of my 78 for about a week now. and I have felt the carpet inside and it's now wet any where it's all dry but I keep smelling antifreeze even when the heater is off. So where could it be coming from? and how do i get to the heater core in my truck to check it out? what would be the easiest way to get to the heater core? thanks guys.

 

anybody have any thoughts on my above post?

 

Geez.. patience! It's the weekend and FTE'ers out are playing with our rigs! Me? I'm on a snack break from working on my 68, 70, and 73.

A small leak may be enough to evaporate and still give off the smell. As the saying goes, "A little goes a long way". Btw, did you actually check both floor boards for moisture? What about checking the coolant level? Notice any drop?

As long as ya don't have AC, removing the heater core is rather straight forward.

Move the lever labeled "Heat" to drain as much coolant in the heater hoses.
Drain the coolant to level below the height of the heater core. Open the petcock.. it's usually on the bottom passenger-side of the radiator.
Mark and disconnect the hoses at the inlet and outlet of the core (firewall side).
At the air plenum, disconnect the ducts, mark and unscrew the lever cables noting which goes where.
Disconnect the wires from the blower resistor and find all the nuts holding the air box. Two are on the firewall side.

R&R the heater core.. they're cheap and good insurance to replace it anyway and one less thing to go bad.

 

would there be any way to do a quick check of the heater core with out tearing everything apart? and yes the carpet on both sides of the floor is dry.

 

Yeah, really!

Give it at least 8 and up to 24 hours.

Well, I wouldn't go so far as to say that, I've read too many experiences out here of the el-Cheapo Chinese-made variants lasting barely over a year.

I would fill it with compressed air and stick it in a bucket of water to look for leaks; if there are none, and the thing otherwise looks to be in serviceable condition, I'd put it back.

I don't see a reason to be replacing factory OEM stuff that's still working fine with el-Cheapo, Chinese-made variants (there's a reason why the OEM units cost lots more).

But that's just my opinion....

 

could I have antifreeze going into my engine? and would I be able to smell it in the cab if It was.

 

A bad head gasket, or a cracked head or block, could allow coolant into the engine.

Depends on where in the engine it enters, but you'll sometimes have oil in your coolant and coolant in your oil.

If it's ending up in the combustion chambers you'll have white "smoke" out the exhaust.

In all cases, I don't think you'd be smelling this inside the cab; the only place in the cab where coolant enters is the heater core, focus on that and the connecting hoses.

With the core removed, attach two short lengths of hose to the outlets; plug one hose (perhaps with a big bolt and a hose clamp) and inject compressed air into the other while the core is in a bucket of water.

I use a blow-gun-type of nozzle in the hose and seal it with duct tape.

It doesn't require much air pressure to see a leak.

 

so then is the heater core located inside the big black box that's under my dash then? or is it some where else behind the dash?

 

Look where the heater hoses connect to it in the engine compartment, it is directly on the other side of the firewall.

 

Opinions are fine. But what's up with the instant and gross assumption that it's going to be a Chinese-made part? The OP could be conscientious and go for OEM-quality.

As far as checking for leaks with compressed air, that's all fine and good. But let's assume that it is not leaking... But it could be clogged given its age and the potential neglect by previous owners.

Personally, I wouldn't cheap out and reinstall it. I'd replace it to establish a KNOWN GOOD baseline....But that's just my opinion....

 

The OEM replacements are something around $100, the Chinese aftermarket ones are around $25.

Not trying to be combative or anything, but you said "they're cheap" which implied (in my mind) an aftermarket replacement from a parts store, please accept my apologies if I misinterpreted.

True, it very well could.

This is why I said: "...and the thing otherwise looks to be in serviceable condition...."

I've read too much stuff here about the Chinese-made starter solenoids & heater cores failing in short order, sometimes right out of the box.

Hence, my recommendation to stay with what he has if it appears to be in good shape and in serviceable condition.

The OEM parts, to me, are a better baseline (assuming they're not shown to have worn out).

 

Thanks for clarifying. It's all good...and a good example of open dialogue here in FTE.

 

was looking through my haynes repair manual and it tell me what has to be removed to get the heater core out of the truck but it doesn't show me what nuts have to be taken off out in the engine compartment. so does any body have a picture from a different repair manual that shows what nuts have to come off under the hood to get the heater box out? thanks in advance.

 

I just did this yesterday twice. I didnt have AC to deal with in either truck. If you do I understand its much more difficult. I removed the glove box door and box. I disconnected the control cables from the unit (2) I removed the vent from the lower passenger floor area. Under the ashtray there were 2 clips holding the floor heating cover...sorry I dont know what to call that. Unplug the unit from the controls.. the plug is almost between where you disconnected the control cables. Then in the engine compartment you need to disconnect the fan motor power and ground wires. Then there are 3 nuts that need to be removed. two by the fan motor and one behind the engine. Once this is all done I just pulled from the cab side and it came out. Its a snug fit but mine both came out. If I missed something hopefully someone will chime in. Then the core needs to be removed from this unit. Hope this helps.

 

well thanks guys for all your help i got the heater box out of my truck last night took me about 20 minutes. so now I just have to go get my new heater core today and maybe a blower motor also will I have all this stuff pulled out. so thanks everybody for the help.