Hex Bushings

Your pump port is 3/4 inch and the part you bought is 1/2 inch. A hex bushing fixes that in one piece. It threads male into the big port, accepts the smaller fitting in its female center, and gives your wrench flats to pull against. Sun Brite Supply carries brass, steel, and stainless hex bushings from 1/8 to 1 inch NPT. Not sure which size you are holding? Call 301-519-9274 and we will sort it out before you order.

Picking the Right Hex Bushing

Order a bushing by naming the male side first, then the female side. A 3/4 MPT x 1/2 FPT bushing screws into a 3/4 inch female port and reduces it to accept a 1/2 inch male thread. MPT means male pipe thread and FPT means female pipe thread, both cut on the NPT taper standard used across American pressure washer gear. The taper is what seals. As you tighten, the threads wedge together, and a wrap or two of thread tape or a dab of pipe sealant fills what the metal misses.

Watch the Thread Size Trap

Pipe thread sizes do not match what your ruler says. A 1/2 inch NPT thread measures about 0.84 inches across the outside. More wrong orders start there than anywhere else. Measure the outside diameter of the male thread, then use this rough decoder: 0.4 inches is 1/8 NPT, 0.54 is 1/4, 0.675 is 3/8, 0.84 is 1/2, 1.05 is 3/4, and 1.32 is 1 inch. Or bring the part to the counter and skip the math.

Brass, Steel, or Stainless

Material choice comes down to where the bushing lives on your rig. Brass handles standard water plumbing, gauge ports, and chemical lines, and it will not rust. Plated steel bushings rated 3,000 PSI or better belong on the discharge side where the pump is making full pressure. 304 stainless in the 150 class is built for low pressure chemical and suction plumbing, and it shrugs off bleach and coastal air that eat brass and steel alike. Do not put a 150 class fitting downstream of the pump. The class number is a pipe schedule rating, not a 3,000 PSI rating.

Size and Price Lookup

Need a size between these, or a stainless reducer in another combination? Call before you settle. We stock more sizes at the counter than the site shows.

From the Field

Two habits save contractors money on fittings. First, do not stack bushings. Threading a 1 to 3/4 into a 3/4 to 1/2 works in a pinch, but every joint is a leak point and the stack sticks out far enough to snag and snap. Buy the single bushing that makes the jump. Second, match metals where you can. A steel bushing left in a brass pump head for a season can seize or gall, and the removal attempt wrecks a $50 port to save a $5 part. A little anti-seize or sealant on the threads means it comes back out next year. And if a joint weeps after tightening, stop cranking. Back it out, clean the threads, re-tape, and retighten. Over-torqued tapered threads split female ports, and a split manifold is not a five dollar fix.

Related Fittings

• Brass pipe fittings
• Stainless steel pipe fittings
• Steel pipe fittings
• Hex couplers for joining two male threads
• Close nipples and nipple fittings
• 90 degree elbows and tees
• Allen head plugs and caps
• Quick connects once your threads are sized right
• All of it is on the shelf at our Gaithersburg store.

Frequently Asked Questions

What is the difference between a hex bushing and a reducer coupling?

A hex bushing is male outside and female inside, so it nests inside the larger fitting and adds almost no length. A reducer coupling is female on both ends and joins two male threads of different sizes. The bushing is the compact choice when you are stepping down at a port.

How do I know what size NPT thread I have?

Measure the outside diameter of the male thread. About 0.84 inches is 1/2 NPT, 1.05 is 3/4, and 1.32 is 1 inch. The nominal size is always smaller than the measured diameter, so never order off a ruler reading alone.

Do hex bushings need thread sealant?

Yes. NPT threads seal by taper, but tape or paste sealant fills the spiral leak path and keeps the joint serviceable later. Two to three wraps of tape, applied clockwise, is plenty.

What pressure can a hex bushing handle?

Depends on material and rating. Our 3,000 PSI steel bushings are made for the discharge side of the pump. Brass is fine for water supply, gauges, and chemical lines. The 150 class stainless bushings are for low pressure chemical and suction plumbing, not the high pressure circuit.

Can I stack two bushings to make a bigger jump?

You can, but you should not. Each extra joint is a leak point and the stack adds leverage that snaps under vibration. Order the single bushing that makes the full reduction.

When should I choose stainless over brass?

Choose 304 stainless when the line carries bleach or harsh chemicals, or the rig lives near salt air. Brass corrodes slowly in fresh water but sodium hypochlorite attacks it. Stainless costs more up front and outlasts brass many times over in chemical service.