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1/4" heater hose outlet on a 440??

moparedtn

I got your Staff Member riiiight heeeere...
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Well, we went from 80F last weekend to actual light snowfall today.
Oy. You'd think we were in New England or something....
Anyways, despite my heater box having suffered rust damage on the inside of the car (and the temperature control flapper door thingy totally flopping loose inside now), I've decided I want to put heater hoses back on the car for winter.

As some of you may recall, this is the hose outlet situation on my 440 right now:
heater outlets now.jpg

The 1/2" outlet to top right is currently occupied by the sensor for my aftermarket temperature gauge; the small temperature sensor to bottom left goes to the factory gauge, of course. Both functional.
That leaves me with the 3/8" outlet (currently plugged off with the silver plug you see here) "down in the hole" and the 1/4" outlet plugged off at top left.

What the hell is up with that, anyways? Is that normal? A 1/4" NPT hole??
I suppose there's some factory adapter of some sort that gets you to heater hose size from there? What are the heater hose sizes supposed to be on a 440 anyways?
I'll be needing both heater hose nipples, I reckon, along with hose itself.

I guess things are supposed to look like this, right?
heater hoses correct.jpg


I will be installing a simple ball valve on one of the lines as well as part of this; when I don't want hot coolant circulating inside, I'll simply turn it off like they did in olden days, right?
Does someone make such a valve especially for heater hose installation or do I just need to grab one out of my stash of crap (we use some regular ol' brass ball valves in my fire sprinkler vocation)??

I need to giddyap on all this, I reckon. The GTX still has only distilled water + Water Wetter in it right now, so a freezin' is a comin' if I don't move my arse. :)
 
5/8" htr. hoses. Man, a 1/4" hole isn't going to flow a whole lot of coolant,but it's doable i guess with some adapters. 38* here at present!
 
5/8" htr. hoses. Man, a 1/4" hole isn't going to flow a whole lot of coolant,but it's doable i guess with some adapters. 38* here at present!
looks like u have a weird pump housing, the small hole is for a temp gauge sender, the 1/2" and 3/8" are for the heater hoses, no biggy, just change it, And u can always work a tee in to the system for something extra. I have a plugged 1/8" temp. hole and two 3/8" pipe holes, w/ heater hoses , fuel inj. sensor and a shut off valve, on an alum. pump housing.
 
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looks like u have a weird pump housing, the small hole is for a temp gauge sender, the 1/2" and 3/8" are for the heater hoses, no biggy, just change it, And u can always work a tee in to the system for something extra. I have a plugged 1/4 temp. hole and two 3/8" pipe holes, w/ heater hoses , fuel inj. sensor and a shut off valve, on an alum. pump housing.
See, that's what I was thinking also, but when I started looking up outlets on other 440 pictures (like the one above), that other heater hose does typically come from where the 1/4" outlet is on mine.
Beats me. :realcrazy:
I could always move the sensor for the under dash temp gauge I guess, but I'd have to come up with some convoluted arrangement for that as well, since the sensor doesn't fit in the 1/4" hole.
 
Well, we went from 80F last weekend to actual light snowfall today.
Oy. You'd think we were in New England or something....
Anyways, despite my heater box having suffered rust damage on the inside of the car (and the temperature control flapper door thingy totally flopping loose inside now), I've decided I want to put heater hoses back on the car for winter.

As some of you may recall, this is the hose outlet situation on my 440 right now:
View attachment 533743
The 1/2" outlet to top right is currently occupied by the sensor for my aftermarket temperature gauge; the small temperature sensor to bottom left goes to the factory gauge, of course. Both functional.
That leaves me with the 3/8" outlet (currently plugged off with the silver plug you see here) "down in the hole" and the 1/4" outlet plugged off at top left.

What the hell is up with that, anyways? Is that normal? A 1/4" NPT hole??
I suppose there's some factory adapter of some sort that gets you to heater hose size from there? What are the heater hose sizes supposed to be on a 440 anyways?
I'll be needing both heater hose nipples, I reckon, along with hose itself.

I guess things are supposed to look like this, right?
View attachment 533749

I will be installing a simple ball valve on one of the lines as well as part of this; when I don't want hot coolant circulating inside, I'll simply turn it off like they did in olden days, right?
Does someone make such a valve especially for heater hose installation or do I just need to grab one out of my stash of crap (we use some regular ol' brass ball valves in my fire sprinkler vocation)??

I need to giddyap on all this, I reckon. The GTX still has only distilled water + Water Wetter in it right now, so a freezin' is a comin' if I don't move my arse. :)
OK don't panic, you just need to look closely at the hole sizes and positions. The rear right is the outlet to the heater which is 1/2 inch, the front right 3/8 is return from the heater. This adds latency for the hot coolant in the heater core. The top left houses another sensor for temperature as does the one below that you already have a sensor in. Both sensors have to be directly in the coolant flow path. The nipple set will have the right threaded end for the two sizes but the nipples above the threads are both 5/8. If you insert a ball valve it goes in the supply hose to the heater not the return. This will lessen coolant pressure on the heater core and prevent aeration of your coolant. The ball valve has to be 5/8 internal passage to work correctly and have the proper nipples for 5/8 hose.
 
OK don't panic, you just need to look closely at the hole sizes and positions. The rear right is the outlet to the heater which is 1/2 inch, the front right 3/8 is return from the heater. This adds latency for the hot coolant in the heater core. The top left houses another sensor for temperature as does the one below that you already have a sensor in. Both sensors have to be directly in the coolant flow path. The nipple set will have the right threaded end for the two sizes but the nipples above the threads are both 5/8. If you insert a ball valve it goes in the supply hose to the heater not the return. This will lessen coolant pressure on the heater core and prevent aeration of your coolant. The ball valve has to be 5/8 internal passage to work correctly and have the proper nipples for 5/8 hose.
panic-button.jpg

Nobody's panicking.:lol:
I appreciate all the great information in your reply.
I suppose then that the layout in the "blue" car above is incorrect?
The reason I wanted to know about the 1/4" outlet I have to spare is, well, obviously these cars didn't come with two temperature sensors on them, so why two holes for them?
It occurs to me that if I were to try and install the probe for my aftermarket gauge in that 1/4" hole, I'd need to increase the size to 3/8" and include a small nipple so that the probe would fit, as it does not fit into a 1/4" hole....and that would take it up out of the flow path, likely into a cavity that would either be an air pocket or at best, would drain down every time system pressure relaxed.
This is why I prefer to use the 1/4" outlet for the hose, mimicking the hoses in the blue car. Of course, that would probably lead to issues with the amount of flow going to the heater core, I suppose.
 
View attachment 533884
Nobody's panicking.:lol:
I appreciate all the great information in your reply.
I suppose then that the layout in the "blue" car above is incorrect?
The reason I wanted to know about the 1/4" outlet I have to spare is, well, obviously these cars didn't come with two temperature sensors on them, so why two holes for them?
It occurs to me that if I were to try and install the probe for my aftermarket gauge in that 1/4" hole, I'd need to increase the size to 3/8" and include a small nipple so that the probe would fit, as it does not fit into a 1/4" hole....and that would take it up out of the flow path, likely into a cavity that would either be an air pocket or at best, would drain down every time system pressure relaxed.
This is why I prefer to use the 1/4" outlet for the hose, mimicking the hoses in the blue car. Of course, that would probably lead to issues with the amount of flow going to the heater core, I suppose.
I found a 3/8" tee shaped shut off valve that looks more "automotive" than a ball valve, on ebay. Even tho I`m a retired plumber ! LOL I stiil have a stock 1968 hemi temp sender in my tool box, it is 1/8" pipe thread, not 1/4" .
 
I found a 3/8" tee shaped shut off valve that looks more "automotive" than a ball valve, on ebay. Even tho I`m a retired plumber ! LOL I stiil have a stock 1968 hemi temp sender in my tool box, it is 1/8" pipe thread, not 1/4" .
I can always just fetch a 5/8" heater hose valve that's cable operated:
HCV2211cableopvalve.jpg

Run a choke-type cable inside the car, then get under the dash and wrangle the busted hot air door open on the HVAC box.
Could work?
 
View attachment 533884
Nobody's panicking.:lol:
I appreciate all the great information in your reply.
I suppose then that the layout in the "blue" car above is incorrect?
The reason I wanted to know about the 1/4" outlet I have to spare is, well, obviously these cars didn't come with two temperature sensors on them, so why two holes for them?
It occurs to me that if I were to try and install the probe for my aftermarket gauge in that 1/4" hole, I'd need to increase the size to 3/8" and include a small nipple so that the probe would fit, as it does not fit into a 1/4" hole....and that would take it up out of the flow path, likely into a cavity that would either be an air pocket or at best, would drain down every time system pressure relaxed.
This is why I prefer to use the 1/4" outlet for the hose, mimicking the hoses in the blue car. Of course, that would probably lead to issues with the amount of flow going to the heater core, I suppose.
I do not know who's gauge you bought but Autometer sensors come with an adapter for both 1/4 and 3/8 tap sizes. The extra hole was for future systems requiring a sensor of sorts like the first primitive ECM's , spark control or vacuum heater controls that won't initiate until the engine is warm. Look on Summit Racing's site for temp probes and you will see that only the tip needs to be in the flow path. Do not mount it otherwise or it will not be able to sense true coolant temperature. The pump housing may have been changed and in your case, that's a good thing. I had to drill and tap a hole on the right side of the housing as I run three sensors.
 
I do not know who's gauge you bought but Autometer sensors come with an adapter for both 1/4 and 3/8 tap sizes. The extra hole was for future systems requiring a sensor of sorts like the first primitive ECM's , spark control or vacuum heater controls that won't initiate until the engine is warm. Look on Summit Racing's site for temp probes and you will see that only the tip needs to be in the flow path. Do not mount it otherwise or it will not be able to sense true coolant temperature. The pump housing may have been changed and in your case, that's a good thing. I had to drill and tap a hole on the right side of the housing as I run three sensors.
Unfortunately, the gauge came with the car. Looks like that probe thingy is permanently affixed to the end of the cable, too, dangit.
As I discovered back when I was going through the engine transplant, a 1/2"NPT to 3/8" compression(?) brass bushing is pretty common for these hookups and in my case, that "cured" things for the time being according to the information on the gauge I was able to find online, so that's where I went with it - very similar to the one shown in the blue car above, in fact.

On yet another front, I have been able to locate heater hose valve nipples that go from 1/4"NPT to 5/8" hose (!). I guess there must be some engine out there somewhere that actually does use a 1/4" outlet for a hose. Go figure.

This being a later model 440, it doesn't surprise me one bit that it has that "extra" 1/4" outlet, as you say. Good ol' Ma Mopar. :)
 
You lazy b------, why do you need cable operated? Plain old "T' handle shutoff, LOL. Seriously could you have an A/C w/p housing? ( is there such a thing). I seem to remember " a car" that had 1/2' & 5/8" htr hoses going to the firewall. I may well be off the wall on the memory. The old brain synapses short-circuit at times, could've been a non-Mopar also.
 
I can always just fetch a 5/8" heater hose valve that's cable operated:
View attachment 534018
Run a choke-type cable inside the car, then get under the dash and wrangle the busted hot air door open on the HVAC box.
Could work?
I thot about this, but not a good fit in my situation. Be great id you have room for it and the cable. My engine compartment is so clutered up now its almost pathetic!
 
You lazy b------, why do you need cable operated? Plain old "T' handle shutoff, LOL. Seriously could you have an A/C w/p housing? ( is there such a thing). I seem to remember " a car" that had 1/2' & 5/8" htr hoses going to the firewall. I may well be off the wall on the memory. The old brain synapses short-circuit at times, could've been a non-Mopar also.
Why you, I oughta...:mad:
I don't wanna open the hood every time I go for a wintry drive? :lol:
 
I thot about this, but not a good fit in my situation. Be great id you have room for it and the cable. My engine compartment is so clutered up now its almost pathetic!
Eh you know, if I was up to ripping the heater box out and restoring the dang thing, I'd fix this correctly.
Not so much right now. Maybe in the future. :)
 
LOL, I kinda looked at my htr box the other day and it really could use an overhaul too; then my back&neck said "just standup and don't worry about it"!! I fondly(?) remember many many upside down under dash days in younger years.
 
now you have me thinking...my GTX has two temp senders (stock and autometer) hooked up and dont remember how the hell I did it. LOL

I must look at the picture archives!
 
now you have me thinking...my GTX has two temp senders (stock and autometer) hooked up and dont remember how the hell I did it. LOL

I must look at the picture archives!
If the picture in your garage is any evidence, you're sort of in the same boat as me - one of your heater hoses is hooked up in the same spot as this 1/4" outlet on mine is.
You have your aftermarket sending unit the same place as mine, too.
i879.jpg
 
I used a housing off of a '63 413. Only option for the mechanical guage was a heater hose fitting. The electric guage sensor is where it goes from the factory.

You can see in this pic just how big the "bulb" and fitting is.
20170620_212239.jpg
 
I used a housing off of a '63 413. Only option for the mechanical guage was a heater hose fitting. The electric guage sensor is where it goes from the factory.

You can see in this pic just how big the "bulb" and fitting is.
View attachment 534666
Yeah, looks like the hole you have is big enough for the probe.
Unfortunately, mine isn't, so I had to put it in the larger hole top right.
 
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