SKF 12551 Shaft Seal 1.25 x 2.125 x .25 in CRWA1 NBR
Rotary shaft seal measuring 1.25 in inside diameter, 2.125 in outside diameter and .25 in width with dual nitrile lips rated for 10 psi and 3,600 RPM
- Product colorTransparent
- Overall width1/4 in
- SKF brand shaft seal trusted for reliable sealing performance
- Nitrile rubber lips resist oils, diesel, gasoline, grease and hot water
- Non-contact CRWA1 design handles up to 3,600 RPM for rotating shafts
- Carbon steel spring maintains consistent lip pressure over time
- Dimensions 1.25 in ID, 2.125 in OD, .25 in width fit standard applications
Application fit
This SKF 12551 rotary shaft seal suits maintenance teams and engine rebuilders who need a direct replacement for a 1.25 in shaft running at up to 3, 600 RPM. It is not intended for buyers who need a higher pressure rating than 10 psi or a different inside diameter.
Sustained operation
The non-contact CRWA1 design with dual nitrile rubber lips and a carbon steel spring maintains sealing against animal and vegetable oils, diesel, gasoline, greases, hot water, light heating oil and mineral oils at continuous speeds up to 6 mps. Acrylic case coating assists installation and resists the listed fluids during extended service.
Critical specification
The decisive figure is the 1.25 in inside diameter matched to a 2.125 in outside diameter and .25 in overall width; only shafts and bores with those exact dimensions will seal correctly with this part.
How it compares
Measured against everything we stock in Engine Service & Diagnostic Tools, at today’s prices. Recalculated every night.
- Price $8.99
- Cheaper than about 90% of the 1,113 comparable items (median $19.99).
Specifications
| Product | |
|---|---|
| Brand name | SKF |
| Product color | Transparent |
| Size & build | |
| Overall width | 1/4 in |
Questions about this item
How much heat or power does the 12551 shaft seal generate when running all day at 3,600 RPM?
The seal is a passive component with no moving parts that consume power; heat comes only from friction against the shaft, which is minimal at the rated 6 mps surface speed and 10 psi pressure limit.
What shaft size and housing bore must I already have for this 1.25 in ID by 2.125 in OD seal to fit?
You need a shaft of exactly 1.25 in diameter and a housing bore of 2.125 in to match the seal's inside and outside dimensions.
Will the NBR lip material and carbon steel spring hold up against the mineral oil and gasoline in my older engine?
Yes, the nitrile rubber lips are compatible with mineral oils, gasoline, diesel, greases, and hot water, making it suitable for older engines using those fluids.
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