The Rotary J157-1 seal kit is the direct replacement for the Rotary lift it came off of. Cross-referenced as ALS-9786-71, it is the genuine Rotary part — same part number, same fit, and same working specification as the one already on your lift. Ordering the Rotary seal kit from us gets you the OEM piece that matches the lift, not an aftermarket knock-off that is close but not the same.

Specifications

• Part number: ALS-9786-71
• Brand: Rotary
• Type: Genuine OEM seal kit

The power unit bundles the motor, pump, reservoir, and valves into one hangable box, usually bolted to a column or a pump stand. Press up and the motor spins the pump, which draws fluid from the reservoir and sends it to the cylinder; release, and the dump valve routes it back. The single spec that matters most is voltage — 110 versus 220 — because the wrong one turns the whole unit into a paperweight.

Hydraulic parts fit by the numbers, and the numbers are unforgiving. A cylinder has to match working length and port type; a hose is spec'd by inner diameter, pressure rating, and end fittings; a power unit lives or dies on voltage. Even seal kits differ by who built the cylinder — the same lift model can carry two cylinder brands with different seal profiles. Order to the actual part, not the lift name.

Related parts for this lift

The parts below are commonly ordered alongside this one — cables, sheaves, seals, and hardware wear on similar schedules, and most repairs go faster when the whole set is done in one visit.

• Air Cylinder - Rotary T140062
• Lower Seal Kit for MOD30 - Rotary - J157-2
• Hydraulic Cylinder $ 1,464.40 $ 1,317.96 - Rotary - T140041
• Air Cylinder Assy (plastic) - Rotary - T100146

Replacing your seal kit

Replacing a hydraulic cylinder comes down to relieving all pressure, capping the lines so nothing gets contaminated, getting the old cylinder out and the new one in, then bleeding the air and leak-checking under load. The exact removal path differs by lift style, and skipping the bleed leaves the lift spongy. Because a cylinder holds a vehicle in the air, the full procedure is worth following start to finish. Full step-by-step: how to reseal a lift cylinder.

Find the right part for your lift

Want to be sure before you buy? Pull the model and serial off your lift's plate and open our Rotary parts lookup to open the exploded parts breakdown for your model — find your part on the drawing and you know it fits. New to finding your model number? our guide to finding your model number covers it, or send a photo of the plate and we will read it for you.

Signs of a hydraulic problem

The fast hydraulic triage: puddle on the floor is an external leak (find it uphill); a lift that won't hold overnight is an internal leak (cylinder or valve); a spongy feel is air or a piston seal; milky fluid is water (service it); a slow or noisy raise is pump, fluid, or air. Match the symptom to the part before you throw a cylinder at a problem that's really a five-dollar washer.

Parts commonly replaced at the same time

Hydraulic parts travel in company: a leaking cylinder often needs a seal kit, a tired hose, and a fluid change all at once. Since you are relieving pressure and bleeding anyway, do the related wear items in the same visit. Tell us your model and we will pull the matching seals, hose, and oil.

Hydraulic fluid

The usual fill is ISO-32 hydraulic oil, with some legacy lifts running Dexron ATF; confirm which your lift uses before topping off and keep the two separate. Bleed after filling and check the level again once the air is out — and see your manual for the exact capacity, which is model-specific.

Safety notes

The failure mode that hurts people is slow drift-down from a bad seal or trapped air, so never leave a hydraulic repair half-bled. Support the lift on its mechanical locks while you work, relieve pressure before opening the system, and cycle it several times empty — watching for drift — before a vehicle goes on it.

Before you order

A little prep prevents a wrong order: confirm model and serial, measure hoses and note fitting sizes, and check whether a reseal solves it before buying a complete cylinder. Budget for oil and bleeding as part of the repair. We will confirm the right part for your production run before it ships.

Check your lift's serial before ordering

The most common reason a lift part comes back is not a defect — it is a revision mismatch. Manufacturers change sub-parts between production runs while keeping the same lift model name, so "it fits my lift model" is not always enough. The model plate carries the serial number that pins your lift to a specific run, and that is the number that settles which version of this part belongs on your lift.

Can't find the plate? Measure the old part — overall length, bolt-hole spacing, thread size on anything threaded — and photograph it from a couple of angles. Send that with your lift's brand and rough age and we will match it against the parts breakdowns we service from every week.

Why buy your Rotary seal kit from Auto Lift Services

We install, inspect, and repair Rotary lifts every week — the ALS-9786-71 is a part we handle in the shop, not a random SKU we drop-ship. The phone answers if you have a question mid-install — call 800-674-9302 — and every part ships genuine, no aftermarket substitution unless you ask for it.