Rescue a leaking front crankshaft seal without replacing the whole damper — the Pioneer Automotive Industries Engine Harmonic Balancer Repair Sleeve HB-1121 restores a smooth sealing surface on a worn harmonic balancer hub. It is a direct-fit replacement for the L6-3.2L, L6-3.3L, L6-3.8L, and L6-4.2L inline-six engines used across a long list of American Motors and Jeep models, including the 1958-1968 American Motors American, 1980-1988 American Motors Eagle, 1974-1983 Jeep Cherokee, 1972-1983 Jeep CJ5, and 1987-1990 Jeep Wrangler — see the Buyer's Guide tab for the full 53-application list.
Over years of running, the front crankshaft / timing-cover seal lip can wear a groove into the balancer's sealing surface, letting engine oil seep past. This sleeve fits over that worn area to give the seal a fresh, round surface to ride against.
Manufacturer part number HB-1121 · GTIN 00727993016497.
What does this repair sleeve do?
It installs over the harmonic balancer's worn hub sealing surface to give the front crankshaft / timing-cover seal a fresh, smooth surface to ride on, addressing oil seepage caused by a grooved balancer.
Will it fit my vehicle?
It is listed for the L6-3.2L, L6-3.3L, L6-3.8L, and L6-4.2L inline-six engines in many American Motors and Jeep models from 1958-1990. Check the Buyer's Guide tab for the full 53-application list.
Do I need a new harmonic balancer too?
Not if the only problem is a grooved sealing surface — the sleeve restores that surface. Diagnose the leak first; a damaged balancer or worn seal may still need its own replacement.
How many sleeves come in the box?
This listing is sold individually with a minimum order quantity of one; the listed applications each use one.
Why is my front cover leaking oil?
A worn seal lip can groove the balancer hub over time, letting oil past. Have the cause diagnosed — if the grooved surface is the culprit, this sleeve provides a fresh surface for the seal.
WARNING: These products can expose you to chemicals including lead and phthalates, which are known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to www.P65Warnings.ca.gov.
