AMT 1640-163-90 1-1/8" Buna Type 21 Carbon/Ceramic Seal Kit
The AMT 1640-163-90 is the genuine 1-1/8" Type 21 seal kit subgroup, combining Buna elastomers with a carbon-against-ceramic face pair. The 1-1/8" size puts this in the larger end of AMT’s range — the pumps that use it move serious volume, and a seal failure on one of them is not a minor drip.
Type 21 is the elastomer-bellows design, and it is a deliberately different approach from the common pusher seal. In a pusher seal a secondary O-ring has to slide a few thousandths of an inch along the shaft as the faces wear down; if scale, rust or crystallised solids build up on that shaft, the O-ring hangs up and the face stops following, and the seal leaks with plenty of carbon left on it. A bellows seal flexes instead of sliding, so there is nothing to seize. On larger pumps handling less-than-clean water, that is a meaningful advantage.
Fit the kit as a complete subgroup — rotating face, seat, bellows and hardware are matched to each other. Make sure the shaft is clean and free of oil where the bellows grips, or it will slip and spin rather than driving the face. Handle both lapped faces by their edges and wipe them with a lint-free cloth immediately before assembly. Confirm the part number against your pump’s parts breakdown before ordering.
Key Features
- Genuine AMT (Gorman-Rupp) seal kit subgroup — supplied as a matched set
- Type 21 elastomer-bellows design — flexes rather than slides, so it resists hang-up on a scaled shaft
- 1-1/8" shaft size for AMT’s larger pumps
- Carbon against ceramic faces for quiet, long-running general service
- Buna (nitrile) elastomers for water, wastewater and general utility duty
Applications
- AMT pumps specifying a 1-1/8" Type 21 mechanical seal
- High-volume water transfer and dewatering service
- Liquids that scale or carry fine solids
- Routine mechanical seal replacement and full pump rebuild work
- Marine, dockside, washdown and industrial water service
Specifications
- Brand: AMT (Gorman-Rupp)
- Manufacturer Part Number: 1640-163-90
- Part Type: Mechanical seal kit subgroup
- Shaft Size: 1-1/8"
- Seal Type: Type 21 (elastomer bellows)
- Face Materials: Carbon / ceramic
- Elastomer: Buna (nitrile)
- Condition: New
Not sure this is the right part? Send us a Picture of the pump plate on your pump and the CLR Marine team will confirm the correct part before you order.
CLRMarine
