Tecumseh HM80 Engine Oil Capacity
The short answer
This guide cannot give a confirmed crankcase oil capacity for the Tecumseh HM80 because no documented specification was available to support one. Rather than repeat an unverified figure, it explains how to find the correct amount for your engine and how to fill it without overfilling or underfilling.
Why the model name alone may not settle it
Tecumseh engines carry a model designation, such as HM80, and a separate specification number, usually stamped on the engine shroud or a tag. That number identifies the exact build. Equipment makers often ordered variants for their own machines, so details can differ between engines that share the HM80 name. Treat any single capacity quoted for the HM80 as provisional until it is checked against the specification number on your engine.
How to confirm the correct amount
Record the model and specification numbers from the engine's identification tag or stamping. Look up those numbers in the Tecumseh service or owner documentation, or in the manual for the machine the engine powers, such as a tiller, snowblower or generator. If you can't find the documentation, a parts or small-engine dealer that works with Tecumseh engines can usually match the specification number to the published capacity and oil recommendation.
Filling when the figure is uncertain
Whatever capacity the documentation lists, the dipstick or fill plug is the final check. Put the machine on level ground and add oil a little at a time. Pause between additions so the oil can settle, then check the level until it reaches the full mark, or the top of the fill opening on engines without a dipstick. When changing oil, some old oil usually stays in the engine. A refill may therefore take less than the full dry-engine capacity. That is another reason to go by the measured level rather than pour in a set amount.
What this guide does not cover
No documented figures were available for the HM80's oil capacity, recommended oil viscosity or service intervals, so none are stated here. Confirm all three in the documentation that matches your engine's specification number before servicing it.