Anyone know the size of these fitting!?!?

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J.B.

J.B.

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I have a 1973 340 block fresh build i bought and my car has heater box delete and i dont need the extra hose fitting i want to cap all 4 off does anyone know the sizes? Refer to photo

IMG_7305.jpeg
 
The two on the right (2 and 3) are for coolant recirculation don't cap those.

The manifold (4) is either a 1/4 or 3/8 pipe thread.

You can tap the fitting on the water pump (1) with a 1/4 pipe tap and use a plug. Pretty sure it's 1/4. Could be 3/8. I did it once.

Get a pipe plug assortment and a couple taps.
 
I have also seen kits with rubber caps and clamps sold as well but do not recall where. As Mean416 said do. Or cap the bypass hose fittings.
 
J.B. said:
I have a 1973 340 block fresh build i bought and my car has heater box delete and i dont need the extra hose fitting i want to cap all 4 off does anyone know the sizes? Refer to photo

View attachment 1716161198
Click to expand...
You've got a couple different things going on there, so I need to clarify a few things.
First, you've got the early (pre-'70) cast iron, driver's side inlet water pump, which uses a 3/4" bypass hose fitting (2). It's hard to tell in the photo because of the tape and everything, but it looks like you've got a later factory or aftermarket manifold that uses a 1" bypass hose fitting (3), possibly the factory '73 manifold?(Edit: Nope, I can see "Edelbrock" on it now that I'm on a laptop) If so, you need to replace it with a reducer and fitting to the appropriate 3/4" size for your water pump and run an early bypass hose.
The early water pump uses fittings for 1/2" heater hose (1). Early (pre-'70 factory, and early aftermarket) manifolds also used fittings for 1/2" heater hose (4). Later factory and current aftermarket manifolds use a fitting for 5/8"heater hose.
Now the good news. The early water pump had thread-in heater hose fittings that can be removed and replaced with (If I recall correctly) a 1/4" pipe plug. The manifold fitting can be removed and replaced with either a 1/4 or 3/8 pipe plug, depending if it's an early or late manifold.
You really should run a bypass hose on a street engine, but a strip only engine can have the nipples removed and plugged.
Edit: Just to be clear, heater hose sizes do not equal fitting sizes; i.e. a 1/2" heater hose generally takes a fitting with 1/4" pipe thread, 5/8" hose uses a fitting with 3/8" pipe thread, etc., although adapter fittings can be found in virtually limitless combinations. I referenced the factory sizes.
Also, on an unrelated note, if that is a '73 motor, it would have originally have had an externally balanced cast crankshaft, and the balancer shown in the picture is for an internally balanced forged crank. Hopefully this means that during your rebuild, the cast crank and balancer were replaced with a forged unit and it's balancer, or at least was rebalanced with the new parts. Factory '73 340s are picky, because they require one-year only parts like convertors and flywheels...
And hopefully that balancer has had it's timing mark properly re-indexed for the passenger side timing tab.
 
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You need the bypass hose.

The water pump needs this path to circulate coolant till the thermostat opens.

Without it the coolant will be static in the block and localize boil.
 
J.B. said:
I have a 1973 340 block fresh build i bought and my car has heater box delete and i dont need the extra hose fitting i want to cap all 4 off does anyone know the sizes? Refer to photo

View attachment 1716161198
Click to expand...
1 and 4 are 5/8" OD. can be plugged with a 3/8" npt plug i believe.
3 and 2 must be connected together using a 1" hose. (might be 3/4 in your case)
 
Mean416 said:
The two on the right (2 and 3) are for coolant recirculation don't cap those.

The manifold (4) is either a 1/4 or 3/8 pipe thread.

You can tap the fitting on the water pump (1) with a 1/4 pipe tap and use a plug. Pretty sure it's 1/4. Could be 3/8. I did it once.

Get a pipe plug assortment and a couple taps.
Click to expand...
Professor Fate said:
You've got a couple different things going on there, so I need to clarify a few things.
First, you've got the early (pre-'70) cast iron, driver's side inlet water pump, which uses a 3/4" bypass hose fitting (2). It's hard to tell in the photo because of the tape and everything, but it looks like you've got a later factory or aftermarket manifold that uses a 1" bypass hose fitting (3), possibly the factory '73 manifold?(Edit: Nope, I can see "Edelbrock" on it now that I'm on a laptop) If so, you need to replace it with a reducer and fitting to the appropriate 3/4" size for your water pump and run an early bypass hose.
The early water pump uses fittings for 1/2" heater hose (1). Early (pre-'70 factory, and early aftermarket) manifolds also used fittings for 1/2" heater hose (4). Later factory and current aftermarket manifolds use a fitting for 5/8"heater hose.
Now the good news. The early water pump had thread-in heater hose fittings that can be removed and replaced with (If I recall correctly) a 1/4" pipe plug. The manifold fitting can be removed and replaced with either a 1/4 or 3/8 pipe plug, depending if it's an early or late manifold.
You really should run a bypass hose on a street engine, but a strip only engine can have the nipples removed and plugged.
Edit: Just to be clear, heater hose sizes do not equal fitting sizes; i.e. a 1/2" heater hose generally takes a fitting with 1/4" pipe thread, 5/8" hose uses a fitting with 3/8" pipe thread, etc., although adapter fittings can be found in virtually limitless combinations. I referenced the factory sizes.
Also, on an unrelated note, if that is a '73 motor, it would have originally have had an externally balanced cast crankshaft, and the balancer shown in the picture is for an internally balanced forged crank. Hopefully this means that during your rebuild, the cast crank and balancer were replaced with a forged unit and it's balancer, or at least was rebalanced with the new parts. Factory '73 340s are picky, because they require one-year only parts like convertors and flywheels...
And hopefully that balancer has had it's timing mark properly re-indexed for the passenger side timing tab.
Click to expand...
Very helpful thank you I actually am going to replace water pump with proper one for 71 demons the radiator port is on passenger side for demon radiator and i notice new polished aluminum pump doesnt have the fittings so was wandering how to keep it all nice and clean. As for the 73 block, the crankshaft and crank internals are 1969
 
The water pump heater port can be tapped and plugged with (I believe) a 1/4 pipe tap. Could be 3/8.
I know, I've done it s couple times on aluminum pumps. I don't know about a factory cast iron one. I suspect you could do the same.
 
Want to get this hi flow polished pump to match valve covers just dont know if the port openings are screw in or push in anyone have this pump?

IMG_7306.png
 
J.B. said:
Very helpful thank you I actually am going to replace water pump with proper one for 71 demons the radiator port is on passenger side for demon radiator and i notice new polished aluminum pump doesnt have the fittings so was wandering how to keep it all nice and clean. As for the 73 block, the crankshaft and crank internals are 1969
Click to expand...
If you change the water pump, you will also need to change the timing cover to the later style so you'll have the timing marks on the driver's side where you can see them ( the WP inlet will cover them with a mismatched setup). Then you will have to make sure the balancer has it's timing marks located correctly for the different timing cover marks.
I am not familiar with the brand of water pump you're looking at, but it appears to have threaded ports that can have MPT plugs screwed into them. Again, don't plug the bypass port- get the correct size fitting and use it.
 
Professor Fate said:
If you change the water pump, you will also need to change the timing cover to the later style so you'll have the timing marks on the driver's side where you can see them ( the WP inlet will cover them with a mismatched setup). Then you will have to make sure the balancer has it's timing marks located correctly for the different timing cover marks.
I am not familiar with the brand of water pump you're looking at, but it appears to have threaded ports that can have MPT plugs screwed into them. Again, don't plug the bypass port- get the correct size fitting and use it.
Click to expand...
Damn i didnt know all that maybe i will just get a different radiator lol that sounds like the easier option and least impactful
 
Professor Fate said:
If you change the water pump, you will also need to change the timing cover to the later style so you'll have the timing marks on the driver's side where you can see them ( the WP inlet will cover them with a mismatched setup). Then you will have to make sure the balancer has it's timing marks located correctly for the different timing cover marks.
I am not familiar with the brand of water pump you're looking at, but it appears to have threaded ports that can have MPT plugs screwed into them. Again, don't plug the bypass port- get the correct size fitting and use it.
Click to expand...
Would my current setup with driver side hose cause any issues with anything other than just changing to a driver side radiator i dont have a radiator yet so thats no sweat
 
Depends on what you have for accessory drives- if you have power steering, each pump style takes a different set of brackets and power steering pump. Same goes for the alternator- slightly different brackets. And then, since the later water pump is deeper than the early iron pump, the pulleys and offsets are slightly different. Go with whatever water pump you have the most parts for.
 
Professor Fate said:
Depends on what you have for accessory drives- if you have power steering, each pump style takes a different set of brackets and power steering pump. Same goes for the alternator- slightly different brackets. And then, since the later water pump is deeper than the early iron pump, the pulleys and offsets are slightly different. Go with whatever water pump you have the most parts for.
Click to expand...
I guess what im saying is dors the 1969 dart driver side radiator mount the same ast the 71 just different outlets because i have all the 69 parts for motor and changing cranks and all that aint happenin

IMG_7308.jpeg
 
If you use all '69 parts, it will fit in a '71. You can't mix and match with '71 parts though. use a set from one or the other.
 
No way in hell I'd spend two hundo on a piece of bling like that. That's silly
 
cudamark said:
If you use all '69 parts, it will fit in a '71. You can't mix and match with '71 parts though. use a set from one or the other.
Click to expand...
Ok perfect so 1969 radiator hoses and 1969 radiator with the 1969 water pump got it.
 
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