Genuine Cummins Onan Green Label canister-style oil filter with bypass valve for HDCAA and HDCAB (Spec A-D) Quiet Diesel RV generators. Oil capacity: 6.7 quarts. Replace every 250 hours. 90-day limited warranty.
The Cummins Onan 187-1000 is the OEM-specified canister-style oil filter for the HDCAA and HDCAB Quiet Diesel RV generator series (Spec A-D). These are liquid-cooled diesel generators with a 6.7-quart oil system — the largest oil capacity of any Onan RV generator family, reflecting the commercial-grade engine at the core of these units.
Like all Cummins Onan Green Label oil filters, the 187-1000 features an integrated bypass valve that allows oil to flow during cold starts or if the filter becomes restricted. Aftermarket "will-fit" filters frequently lack bypass valves — as these filters trap debris, oil pressure starvation can occur, leading to elevated pressures, failed gaskets, and serious engine damage on a diesel engine. The bypass valve is non-negotiable for this application.
Integrated bypass valve allows oil to flow during cold starts and if the filter becomes restricted — prevents starvation, high oil pressure, failed gaskets, and engine damage
Tested and designed specifically for HDCAA and HDCAB Quiet Diesel RV generators — meets OEM specifications; canister-style design for these liquid-cooled engines
Longer 250-hour oil change interval vs. earlier Onan diesel families — reflects the liquid-cooled commercial-grade engine in the HDCAA/HDCAB series
HDCAA and HDCAB generators hold 6.7 quarts of oil — plan accordingly when performing a full oil and filter service on these larger generators
This filter fits the HDCAA and HDCAB (Spec A-D) Quiet Diesel RV generator series only. It is not compatible with other Onan diesel generator families, each of which uses a different oil filter: • HDKCA / HDKCB — use 122-0893 • HDKAJ / HDKBA / HDKAH — use 122-0833 • HDKAG / HQDPB — use 185-5835 • DKC RV / DKD RV / DKG — use 122-0827 Confirm your generator's model designation from the identification nameplate. The HDCAA and HDCAB are liquid-cooled diesel generators — if your generator is air-cooled, it is not an HDCAA/HDCAB and this is not the correct filter.
Cummins Onan recommends changing the oil and filter every 250 hours on HDCAA and HDCAB generators. If the generator has not reached 250 hours in a year, change the oil annually regardless. Change more frequently in dirty or dusty conditions. The HDCAA/HDCAB system holds 6.7 quarts of oil — significantly more than other Onan RV generator families. Plan for adequate oil supply when servicing. Always refer to your operator's manual for final guidance — if there is any discrepancy, the manual takes precedence.
Backed by a 90-day limited manufacturer's warranty against defects in materials and workmanship. Cummins Power Generation warrants only the quality and integrity of Green Label Parts. Damage caused by the use of non-Green Label or non-bypass oil filters is not covered under the Cummins Onan limited warranty.