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Obsolete Parts
When the manufacturer stops making the part
A discontinued part number is not the end of the road. The number was only ever a label attached to a set of dimensions, and the dimensions are still sitting in your hand. This is how an assembly nobody catalogs gets rebuilt from the one that failed.
SAE J517 lists 100R1A, 100R2A, 100R2B, 100R2BT, 100R9, 100R10 and 100R11 as discontinued, and names what replaced them. Obsolescence is written into the standard.
CFC-12 was banned in new vehicles from 1994 after roughly thirty years of use, and EPA requires a unique fitting set for every approved replacement refrigerant.
Bore, construction and rating, both end types, thread and seat, orientation, and installed length. Get those and the part number is decoration.
The premiseObsolescence is normal, and it is documented
People treat a discontinued part as an unusual misfortune. It is closer to a scheduled event. Equipment outlives its parts catalog as a matter of routine, and the industry that supplies those parts writes the obsolescence down in public.
The clearest example is the standard that governs hydraulic hose itself. SAE J517 has been in continuous revision since 1952, and it does not quietly drop things. It records them. The standard states that 100R9, 100R10 and 100R11 were discontinued for lack of demand, and that 100R1A, 100R2A, 100R2B and 100R2BT went the same way, with instructions on what to substitute.
That last detail is the one worth holding onto. The types that disappeared were largely thick-cover constructions that required skiving before a fitting could be attached. What replaced them were the AT variants, which take a no-skive fitting. The part changed because the method changed, and the standard tells you so.
| Discontinued | Replaced by | Why it went |
|---|---|---|
| 100R1A | 100R1AT | Thick cover requiring skiving, superseded by the no-skive construction. Lack of demand. |
| 100R2A | 100R2AT | Same reason. Two-wire braid, thick cover, skive fitting. |
| 100R2B | 100R2AT | Two-wire spiral variant, withdrawn for lack of demand. |
| 100R2BT | 100R2AT | Withdrawn alongside the other R2 variants. |
| 100R9, 100R10, 100R11 | See current spiral types | Four and six wire spiral constructions, discontinued for lack of demand. Modern spiral types cover the pressure range. |
If a machine built in the 1990s has a plate calling for 100R2A, that hose does not exist to buy anymore. It has not become unobtainable in the sense people fear. It has been superseded by a construction that meets or exceeds the same requirement, and the standard names it. A great deal of what looks like an obsolete part problem is really a superseded specification problem, and those two need very different answers.
The same pattern repeats everywhere. A refrigerant gets phased out and takes the fittings with it. A vessel manufacturer stops supporting a hull from thirty years ago. A production machine is sold, moved twice and ends up in a shop that has never seen the manual. In each case the paperwork disappears long before the machine does.
The patternWhich categories go obsolete first
Not everything ages at the same rate. Five categories account for most of what comes across our counter with no part number attached, and they get there by different routes.
Boats stay in service for decades while the companies that built them merge, fold or move on. A thirty year old hull is common and entirely serviceable, and its steering, fuel and exhaust lines were specified by a business that may no longer exist in any form you can call.
Salt accelerates everything on top of that, so marine assemblies need replacing more often than the equivalent on land while being harder to source. The one thing that has not gone away is the requirement the hose has to meet, which is a topic in its own right and one we will come back to. See marine hoses and fittings.
This one has a regulatory cause rather than a commercial one. CFC-12 was used in vehicle air conditioning for around thirty years and banned in new vehicles from 1994. Anything older is either still running the original refrigerant or has been retrofitted at some point by somebody.
The complication is that EPA requires each approved replacement refrigerant to use a unique set of service fittings specifically so refrigerants cannot be mixed, and states plainly that an adapter should not be used to convert a fitting. So on a car of that age, the ports may not match the manual, the retrofit may have introduced hardware the factory never fitted, and the only reliable specification is the car in front of you. See A/C hoses and lines.
Manufacturers support parts for a period and then stop, and specialty and low-volume models fall off first. Brake tubes and flexible brake hoses on those vehicles become genuinely hard to buy while the vehicles themselves keep passing inspection and driving.
Brake work carries an obligation the rest of this does not. An assembly built for a road vehicle has to conform to FMVSS 106 and be marked accordingly, and there is no such thing as a DOT approval process that anybody applies for. That distinction is covered fully in what the DOT marking really means. See brake, fuel and power steering hoses.
Industrial machinery is built to last and frequently does, which means a working press, mixer or conveyor can easily outlive the company that made it, or survive two acquisitions and a relocation with no documentation following it.
These are often the highest consequence failures in this article, because the machine may be the only one of its kind on the floor and there is no workaround while it waits. The parts themselves are usually straightforward once identified, which is the frustrating part. See industrial hose assemblies.
Breakers, augers, mowers and grapples change hands repeatedly and rarely travel with their paperwork. By the third owner the plate is often painted over or missing, and the machine it now hangs off is not the machine it was specified for.
These usually turn out to be the easiest to solve, because the fittings are commonly standard and the assembly is short. The obstacle is identification rather than availability. See hydraulic fittings and adapters.
Difficulty to source▮▮▮▮▮ hardestBased on what arrives at our counters, not a published index.
The principleThe part number dies, the specification does not
A part number is an index entry. It points at a set of physical properties, and it is the pointer that gets discontinued, not the properties. Once you accept that, the problem changes shape entirely. You are no longer looking for a number nobody has. You are describing an object, and objects can be described.
Six properties define almost any hose assembly. Capture those and it can be built, whether or not anybody ever catalogs it again.
- Inside diameter. The bore, usually expressed in dash size where one dash equals a sixteenth of an inch. This determines flow and is not negotiable, because a smaller bore starves the circuit and a larger one changes system behavior.
- Construction and pressure rating. How many layers of reinforcement and of what. This is the property most often readable straight from the cover, and the one that decides whether the replacement is safe.
- End types. What is on each end, which are frequently not the same. A straight JIC one end and a 90 degree ORFS the other is entirely ordinary.
- Thread and seat. The thread standard and the sealing method. A 37 degree cone and a 45 degree cone will thread together and never seal, which is covered in detail in our fittings identification guide.
- Orientation. The rotational angle between the two ends. Ignored constantly and the single most common reason a correctly specified assembly will not fit the machine.
- Installed length. Measured to a convention, with the slack the routing needs. Wrong here and the hose either fouls something or pulls tight at the crimp.
Most hose carries printed information along the cover: manufacturer, type designation, bore, pressure rating and often a date. If any of it survives, photograph it before you clean the part. On assemblies that have been in service for twenty years the printing is usually partial, and a partial layline plus the physical part is still enough to work from.
The Worksheet
Capture the specification
Work through the six points on the drawing. Fill in what you can read from the part and leave the rest blank, because a partial sheet is still far more useful than a phone call that starts with a machine model. Copy it when you are done and bring it with the hose.
Inside diameter
Measure the bore at a clean cut end, not the outside of the cover. Dash sizes run in sixteenths, so a half inch bore is a dash 8. If the layline is legible it will usually give you this directly and save the measuring.
Nothing recorded yet. Even two of six is enough to start a useful conversation.
Nothing is sent anywhere and nothing is stored. This runs in your browser and disappears when you close the tab, so copy it before you leave.
PracticalGetting the old one off without destroying the evidence
The failed assembly is your specification, so how it comes off the machine matters. A hose cut in half at the middle with both ends left behind is close to useless. A hose removed whole with both fittings attached is almost a complete drawing.
Photograph it in place first
Before anything is loosened, take pictures of the routing from two angles, including which clamps and guides hold it where. Routing is the one property that cannot be recovered from the part afterwards, and on a machine that gets stripped it is gone permanently.
Note which way the ends point
Mark the orientation with a paint pen or a piece of tape across both fittings before you break the joints. Once the assembly is off the machine and relaxed, the angle between the ends is easy to lose and awkward to reconstruct.
Remove it whole
Both fittings attached, hose uncut. Old fittings can very often be cleaned up and reused, which on obsolete work is frequently the entire solution, because the fitting is the part nobody sells and the hose is the part everybody does.
Photograph the layline before cleaning
Degreaser and a wire brush take printed markings off in seconds. Whatever is still legible on the cover is free information, so capture it while it exists.
Keep the failure evidence
Where it burst, where it rubbed, whether the cover was cracked or the fitting pulled. That tells us whether to build the same thing again or change the routing, the construction or the cover. More on reading those signs in warning signs fleet managers miss.
Bring it in, or send pictures with a ruler in frame
The part in hand is always faster. If it genuinely cannot leave the machine, photographs with a tape measure or a caliper alongside each end will get most of the way there.
The exceptionWhere copying the original is the wrong answer
Rebuilding from a sample assumes the original was correct. Usually it was. In three situations it is not, and reproducing it faithfully would repeat somebody else's mistake or ignore a rule that changed after the part was made.
When the original was already a repair
Equipment gets fixed by whoever was available. The assembly on the machine may be a previous substitution, an adapter stack somebody built to bridge two standards, or a hose that was close enough at the time. Copying it faithfully copies the compromise, which is why we look at why it failed rather than only at what it is.
When the rules moved
Automotive A/C is the clearest case. EPA requires each approved refrigerant to use unique service fittings precisely so refrigerants cannot be cross charged, and states that an adapter should not be used to convert a fitting. A system retrofitted from CFC-12 has hardware the factory never fitted, and retrofits also carry labeling requirements covering the refrigerant, the charge amount and the lubricant used.
Fuel is the other. Rubber specified before ethanol appeared in pump fuel was never tested against it, which is covered in hose customization in auto restoration. The original specification can be authentic and wrong at the same time.
When certification attaches to the assembly
Brake hose is the example that matters most. A hydraulic brake hose assembly for a road vehicle has to conform to FMVSS 106 and carry the marking, and that obligation attaches to whoever builds the assembly. It is not inherited from the part it replaced. Nothing is DOT approved in the sense the phrase implies, because certification under that system is a declaration by the manufacturer rather than a permission granted by an agency.
Not "what was on here," but "what does this machine need." Those give the same answer most of the time. When they diverge, the second one is the one to build, and the divergence is worth writing down and keeping with the machine so the next person understands why the part does not match the manual.
LimitsWhat cannot be rebuilt this way
Being straight about the boundary is more useful than implying anything is possible. Four categories genuinely do not work from a sample.
Molded and formed hose
Coolant and heater hoses with compound bends molded in are produced on a mandrel from a tool. A flexible equivalent can sometimes be routed with the right supports, but the exact molded shape is not something a counter reproduces.
Integrated assemblies
Where the hose is permanently part of a larger component, a valve body, an accumulator or a sensor housing, the hose is not separable. That becomes a component sourcing problem rather than a hose problem.
Rigid line with formed bends
Hard tube with specific bend geometry needs bending to the original shape, which is a different trade. Bringing the old line as a pattern is essential rather than helpful there.
Anything with no readable evidence
If the part is destroyed, the machine is unidentified and there is no plate, there is nothing to work from. A photograph of the port and the machine model is usually enough to restart the process, but a guess is not a specification.
At the counterHow this actually goes
Building from a sample is ordinary work here rather than a special service. Sixty years of it means the awkward cases are familiar rather than novel.
- Identification with gauges, at no charge. Thread pitch, thread angle, seat and diameter, settled in about thirty seconds rather than argued about over the phone.
- Original fittings cleaned up and reused where they are sound, which on obsolete work is often the whole answer.
- Cross-referencing superseded specifications against what current standards call for, so a plate calling out a withdrawn type gets the correct modern equivalent.
- Built while you wait at both counters wherever the components are on the shelf. See custom hose fabrication and OEM hose assembly replacement.
- Crimped to matched components rather than mixed systems, which matters more on rebuilt assemblies than on catalog ones. See hydraulic hose crimping.
- A second one made at the same time if the machine has no backup, because the cheapest moment to build a spare is while the specification is already on the bench. The arithmetic behind that sits in what an hour of downtime actually costs.
Marine, automotive, industrial, pneumatic and fuel transfer all get the same treatment. Full range on the products page, including pneumatic quick disconnect fittings and fleet fuel transfer.
Long Island since 1964
Sixty years in the same two towns means we have watched a lot of part numbers disappear while the equipment carried on working. Hempstead in Nassau County and Oakdale in Suffolk County, with regular work into Queens and across the metro area.
Obsolete work is the case where bringing the part in is not just faster, it is the only reliable route. There is no catalog to look it up in and no number to read down the phone. There is an object, and it needs to be in front of somebody who can measure it.
Common Questions
Obsolete assembly FAQ
Yes, and it is routine. A part number only points at physical properties. Six of those define almost any assembly: inside diameter, construction and pressure rating, the type of each end fitting, the thread and seat, the rotational orientation between the ends, and the installed length. Capture those from the failed part and the assembly can be built whether or not anybody still catalogs it.
That type was withdrawn from SAE J517 for lack of demand, along with 100R1A, 100R2B and 100R2BT. The standard directs those to the AT variants, so 100R2A becomes 100R2AT. The older types used a thick cover that required skiving before a fitting could be attached, and the AT constructions take no-skive fittings instead. It is a superseded specification rather than an unobtainable part.
The old assembly, removed whole with both fittings still attached and the hose uncut. Add photographs of how it was routed before you took it off, and of the layline before you clean anything, because degreaser removes printed markings in seconds. If the part cannot leave the machine, photographs with a tape measure or caliper alongside each end will get most of the way there.
Often, and on obsolete work that is frequently the whole solution. The fitting is usually the part nobody sells anymore while the hose is the part everybody does. If the sealing faces and threads are sound, an original fitting can be cleaned up and put onto new hose, which keeps the machine-side connection correct without sourcing anything.
Because it was probably retrofitted. CFC-12 was banned in new vehicles from 1994, and EPA requires each approved replacement refrigerant to use a unique set of service fittings so refrigerants cannot be mixed, stating that an adapter should not be used to convert a fitting. A retrofitted system also has to carry a label recording the refrigerant, the charge amount and the lubricant. On a car of that age the vehicle in front of you is the specification, not the manual.
Usually, but not always. The assembly on a machine may itself be an earlier substitution or an adapter stack somebody improvised, in which case copying it repeats the compromise. Rules also change after a part is made, which is why refrigerant fittings, ethanol-resistant fuel line and brake hose certification can all make the original specification the wrong thing to reproduce.
They can be built, and the obligation travels with whoever builds them. A hydraulic brake hose assembly for a road vehicle has to conform to FMVSS 106 and be marked accordingly, and that requirement attaches to the new assembly rather than being inherited from the old one. There is no DOT approval process to apply for, because the mark is the manufacturer's own certification of conformity.
Four things. Molded coolant and heater hoses with compound bends formed on a tool. Assemblies permanently integrated into a larger component such as a valve body or accumulator. Rigid tube with specific formed bends, which is a different trade. And anything where the part is destroyed, the machine is unidentified and no plate survives, because at that point there is no evidence to work from.
Ask The Counter
Send us what you have
Paste the spec sheet from above, or send photographs of the failed assembly with a tape measure in frame. Tell us the machine if you know it. Somebody who does this daily will tell you whether it is a five minute job or a real problem.
- SAE J517, Hydraulic Hose. The 100R series specifications, and the record of which types were discontinued and what replaced them.
- EPA, Choosing and Using a Retrofit Refrigerant for a CFC-12 MVAC. Unique fitting requirements and retrofit labeling.
- EPA, Regulatory Requirements for MVAC System Servicing. SNAP program conditions for approved refrigerants.
- NHTSA interpretation on self-certification. Why no product is DOT approved and what the marking actually declares.
No Part Number Required
Bring the one that came off
Two Long Island counters, six days a week. Measured, matched and built from the failed assembly, including the fittings nobody stocks anymore.