Bypass hose and fitting dilemma

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prorac1

prorac1

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1983 318 with an early 273 timing cover and drivers side water pump. Holley aluminum intake.

Water pump and intake has no fittings. Just 3/4 pipe thread holes.

Here's the dilemma. I picked up both bypass hoses. Early and late. Than I picked up some 3/4npt x 3/4" barb fittings.

Than I discover that the late model hose is 1" ID (way to big), but the early hose is still 13/16". Lol.

3/4 npt x 3/4" barb is the biggest brass fitting I've been able to find.

The 3/4 barb fits the 13/16" hose "OK", and it might snug up with the hose clamps. But it dosent slip onto the barb as snug as I would like.

What's every one running and where do you get your fittings? Menards isn't getting it done for me this time. Lol.

Also need to source the 3/8 npt x 5/8 heater hose fittings as well.

Thanks. Eric
 
Go down to HD or Lowes and buy a 3/4" nipple x" long, say, 6. If you don't have some way to clamp it without thread damage, buy a coupling "or something" so you can clamp it in the vise. Go home, saw the thing off so you have threads and an appropriate length of nipple, and install your hose.

If you are "inventive" you can pliers tighting the thing "way out" at the end so the hose goes over any scarring and the clamp is up near the threads, IE it will seal
 
found this on _ b_y to use on my 69 340 barracuda works great
water pump bypass hose barb 1 inch barb to 1/2 npt
1" HOSE BARB X 1/2 MALE NPT Brass Pipe Fitting NPT Thread Gas Fuel Water Air 713807495282 | eBay
s-l140.jpg
 
67Dart273 said:
Go down to HD or Lowes and buy a 3/4" nipple x" long, say, 6. If you don't have some way to clamp it without thread damage, buy a coupling "or something" so you can clamp it in the vise. Go home, saw the thing off so you have threads and an appropriate length of nipple, and install your hose.

If you are "inventive" you can pliers tighting the thing "way out" at the end so the hose goes over any scarring and the clamp is up near the threads, IE it will seal
Click to expand...


I'm assuming this is because the 3/4npt nipple has the same tube diameter as the 1" hose, and your not dealing with barb size?
 
prorac1 said:
I'm assuming this is because the 3/4npt nipple has the same tube diameter as the 1" hose, and your not dealing with barb size?
Click to expand...

Yes 3/4 is pretty close to 1" OD

On a side note, 1/8 is close enough to 3/8OD that you can use it sometimes for fuel connections, and 3/8 is close to 5/8 for heater hose use.
 
There is a place called FittingsandAdapters.com that has all of those fittings you can't find elsewhere. The one for the Holley intake is part no. BHB-12-12, 3/4 hose id. and 3/4 male pipe thread. I'm sure they have the water pump fitting also. You have to look real hard on their website so you don't overlook them.
 
You can also get a kit from Summit or Mopar Performance that includes the hose, clamps, and one 3/4 npt x 1" nipple. If your water pump is 3/4 npt also, you can get another fitting separately. Just went through this, also.
 
Go to the u-pull with a pipe wrench and a strap wrench.

I also have, believe it or not, a gate hinge that works in the slots of the nipple.

They might not even charge you.

I always harvest the ones from my used pumps before they either go back as cores or go to scrap.
 
krazykuda said:
Grainger

6AFJ5 = 3/4" pipe thread with 1" nipple

GRAINGER APPROVED Hose Barb,1 In Barb,3/4 In MNPT,Brass - 6AFJ5|6AFJ5 - Grainger


6AFH7 = 3/8" pipe thread with 5/8" nipple...

GRAINGER APPROVED Hose Barb,5/8 In Barb,3/8 In MNPT,Brass - 6AFH7|6AFH7 - Grainger


View attachment 1715162837

View attachment 1715162838
Click to expand...

Went to granger this morning on my way to work and ordered all 4 fittings. They should be in tomorrow. Thank you again for all the help everyone. Eric
 
By the way use teflon tape or sealant to keep the threads from sticking and RESIST the urge to tighten them. Just snug them........REMEMBER---pipe threads are tapered and you can easily break a casting, 'specially 'luminum, and even iron
 
prorac1 said:
Went to granger this morning on my way to work and ordered all 4 fittings. They should be in tomorrow. Thank you again for all the help everyone. Eric
Click to expand...
The part has changed and the hose end is now barbed.
 
Just in case anyone is researching bypass hose fittings, just got this machined 3/4npt stainless bypass hose barb, a tick under $19 shipped from a seller on EBay. Looks nice enough, maybe nicer than an iron pipe stub, is more pricey than most options given already, but much cheaper than the Mopar barb that's available.

IMG_20190326_062102.jpg
 
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Does anyone else go to the effort to whittle away 2 or 3 barbs so the clamp sits on a flat surface behind a single barb like OEM nipples?
 
12many said:
Just in case anyone is researching bypass hose fittings, just got this machined 3/4npt stainless bypass hose barb, a tick under $19 shipped from a seller on EBay. Looks nice enough, maybe nicer than an iron pipe stub, is more pricey than most options given already, but much cheaper than the Mopar barb that's available.

View attachment 1715309383
Click to expand...
Perfect thats it exactly except I'm pretty sure Stainless will react with Aluminum. From a metals Article I read:

Last Updated on October 4, 2018

Corrosion develops when two dissimilar materials are combined in a corrosive electrolyte. This can occur when certain materials (such as aluminum) are in contact with stainless steel.

The most common solution to prevent galvanic corrosion is to select metals that are close together in the galvanic series. Separating the metals that are incompatible reduces the risk of these cells deteriorating. According to the levels of galvanic corrosion, stainless steel that comes into contact with materials such as copper is less likely to be a risk than when it is in contact with aluminum.

Although aluminum reacts negatively to stainless steel, large surface areas of aluminum to stainless steel can be acceptable depending on local environmental conditions. Severe corrosion is likely to take place in a marine environment. However, there are methods that can be used to reduce this effect. A good way to reduce corrosion is to use an isolating coating or paint on the aluminum and the steel to isolate them electrically. Insulating washers are also effective in isolating the two dissimilar materials and creating a relatively safe surface area.
 
I hit a deer a few years ago in the 67 sweptline on my way to work. The fan cut a nice circle in the radiator. Drove home with a couple of 5 gallon jugs of water to fill up when it got really hot.I had to stop several times!

At home I had a 70 radiator with the outlet on the opposite side, so I had to put a used 70 up water pump on with the 1" nipple. The intake nipple was the smaller one. I was working 12 hour shifts, and it was getting late, so I just wrapped electrical tape around the intake's nipple until the 1" bypass hose fit snuggly, and clamped it down. I drove it to work the next day.

That "temporary fix never did fail even though I really overheated the 318 several times. (The newer style pumps are longer, so there was no room for a fan.)
I drove it daily like that for years, but man it would get hot if Mc Donalds drive through was busy, but i had to have my bacon egg and cheese biscuit!
 
Mega parts carries the nipples, as do, probably, all the other restoration sites.
 
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