67 Fury with a 383 - anyone know what pipe thread size is on the engine block for the heater hose inlet and outlet? Wanting to convert it from 5/8" to 1/2", very annoyingly, the heater core I've got is 1/2" on both barbs, and I bought a whole length of 1/2" heater hose and of course I neglected to see what size the outlets were when fixing up the heating system.
67 383 engine block heater inlet and outlet pipe thread size?
- Thread starter edbods
- Start date
200%. The 1/2 inch hoses I got would not fit if they weren't. I know the block fittings are currently 5/8" because the 1/2" hose is way too small for either one of them.
Sorry for the confusion - it's actually a 67 Dodge Phoenix, the aussie version of the same year Fury III. I just mentioned 67 Fury because it's familiar with you guys across the pond. These came with either the 318 or 383, mine is a 383. Unlike the heater core in our cars, the engines weren't locally produced so I know there's no shenanigans like oddball parts and/or standards used in their manufacture.
Sorry for the confusion - it's actually a 67 Dodge Phoenix, the aussie version of the same year Fury III. I just mentioned 67 Fury because it's familiar with you guys across the pond. These came with either the 318 or 383, mine is a 383. Unlike the heater core in our cars, the engines weren't locally produced so I know there's no shenanigans like oddball parts and/or standards used in their manufacture.
3/8-18 NPT is the size.
I think Australia uses British Standard Pipe Threads (BSPT) instead of National Pipe Thread (NPT) as their standard plumbing fittings. The difference is the BSPT has 55° angle on the threads and NPT is 60°. The two do not interchange. So a local hardware store might not have what you need. FWIW, there's also a JIS pipe thread (Japanese International Standard) that interchanges with the BSPT.
I think Australia uses British Standard Pipe Threads (BSPT) instead of National Pipe Thread (NPT) as their standard plumbing fittings. The difference is the BSPT has 55° angle on the threads and NPT is 60°. The two do not interchange. So a local hardware store might not have what you need. FWIW, there's also a JIS pipe thread (Japanese International Standard) that interchanges with the BSPT.
I also think they should be 5/8" heater hose. Of course, someone could have changed the heater core for something that fit or the Aussie car just takes 1/2".
I strongly suspect it used a 1/2 heater core from the factory, the original rivets sealing up the core were still there unless someone was actually bothered enough to use new rivets. The heater valve also seems to be some local model, a 90° valve with 1/2" barbs on either end. It's pretty much impossible to find so I had to use a 1/2" push-to-close valve from a British motoring performance shop. The old valve:
Versus the new valve I got:
The barbs were just a tad bit large for the hose I got, so I ended up grinding them down a bit to make it fit easier. The barbs also have a sharp edge which will cut into the hose leaving rubber shavings behind, so I made a smooth bend of that as much as I could. The great thing about this valve is that it's apparently fully serviceable, can be taken apart if it needs to be cleaned out. The only drawback is that the heater temp lever in the dash doesn't actually cover the full range of this valve; adjusting the cable so that it's fully closed means that when the lever is fully opened, the valve itself is actually only about 60% open. Adjusting the cable it so it fully opens then results in the fully closed position still actually allowing some coolant to flow through. As far as I can tell, an attempt to fix this would require removing the in-dash lever and bowden cable clamp, and cutting and welding something up, and doing so at the heater valve itself would require extending the lever and bracket that the valve is screwed on to.
Thanks Big John, I've found some local shops that sell 3/8 NPT to 1/2" barbs so I might just change those out.
Versus the new valve I got:
The barbs were just a tad bit large for the hose I got, so I ended up grinding them down a bit to make it fit easier. The barbs also have a sharp edge which will cut into the hose leaving rubber shavings behind, so I made a smooth bend of that as much as I could. The great thing about this valve is that it's apparently fully serviceable, can be taken apart if it needs to be cleaned out. The only drawback is that the heater temp lever in the dash doesn't actually cover the full range of this valve; adjusting the cable so that it's fully closed means that when the lever is fully opened, the valve itself is actually only about 60% open. Adjusting the cable it so it fully opens then results in the fully closed position still actually allowing some coolant to flow through. As far as I can tell, an attempt to fix this would require removing the in-dash lever and bowden cable clamp, and cutting and welding something up, and doing so at the heater valve itself would require extending the lever and bracket that the valve is screwed on to.
Thanks Big John, I've found some local shops that sell 3/8 NPT to 1/2" barbs so I might just change those out.
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Yes, you should. I like Permatex. #2 myself, but any pipe thread sealant should work. Generally speaking, I don't like to use Teflon tape on any automotive parts because of the shreds of the tape getting into whatever you're sealing, but it would also work.
Alright. Finally got off my lazy *** and swapped out the barbs. Luckily for me the outlet hose side (the one closer to the front of the car) was able to be removed without having to remove the entire hex extension thingy. The barb threads are indeed 3/8" NPT.
For any aussies here, Bunnings has some pretty cheap thread sealant, Boston thread sealant 50 mL for just $7.50 as of this post. Loctite 243 can be got from there too but it's $12.40 for 10 mL.
Before and after:
Removing the alternator and its brackets gives a lot more room to work with and in fact I doubt you'd be able to replace the barbs at all without doing that first. the barb for the heater outlet hose (front of engine) was pretty hard to break loose, I had to wedge a wrench against the water outlet housing to stop the hex extension bit thingy from turning as well, you can see it in the first pic. Once I got it off, it seemed like just two or three threads were actually engaged, there were deposits/scaling on the rest of the thread inside that extension bit as well as a small amount inside the barb. I didn't bother cleaning the extension out and just stuck the new barb on it with sealant. The inlet barb was much easier to remove, and I suspect it had been replaced at some point as it looked different compared to the outlet barb. With the new barbs, I just tightened them till they gave more resistance than usual while turning the wrench.
Inlet barb on left, outlet on right:
I think I mentioned it before but somehow the heater core was still fully sealed, so I just filled it up with demineralised water and called it a day. Hopefully within this week, I finally get around to the 4 bbl conversion...
For any aussies here, Bunnings has some pretty cheap thread sealant, Boston thread sealant 50 mL for just $7.50 as of this post. Loctite 243 can be got from there too but it's $12.40 for 10 mL.
Before and after:
Removing the alternator and its brackets gives a lot more room to work with and in fact I doubt you'd be able to replace the barbs at all without doing that first. the barb for the heater outlet hose (front of engine) was pretty hard to break loose, I had to wedge a wrench against the water outlet housing to stop the hex extension bit thingy from turning as well, you can see it in the first pic. Once I got it off, it seemed like just two or three threads were actually engaged, there were deposits/scaling on the rest of the thread inside that extension bit as well as a small amount inside the barb. I didn't bother cleaning the extension out and just stuck the new barb on it with sealant. The inlet barb was much easier to remove, and I suspect it had been replaced at some point as it looked different compared to the outlet barb. With the new barbs, I just tightened them till they gave more resistance than usual while turning the wrench.
Inlet barb on left, outlet on right:
I think I mentioned it before but somehow the heater core was still fully sealed, so I just filled it up with demineralised water and called it a day. Hopefully within this week, I finally get around to the 4 bbl conversion...
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