# Freewheeling Engine **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [February 8, 2011, 3:17pm UTC](https://community.cartalk.com/t/freewheeling-engine/61058 "2011-02-08T15:17:37Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![aptwoap](https://avatars.discourse-cdn.com/v4/letter/a/c37758/32.png) [@aptwoap](https://community.cartalk.com/u/aptwoap)\ **Post date:** [February 8, 2011, 3:17pm UTC](https://community.cartalk.com/t/freewheeling-engine/61058/1 "2011-02-08T15:17:37Z")
What does the term “freewheeling” mean? How does it differ from a “non-freewheeling” engine ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [February 8, 2011, 3:30pm UTC](https://community.cartalk.com/t/freewheeling-engine/61058/2 "2011-02-08T15:30:04Z")
I thing ‘freewheeling’ means an engine that, when you let off the gas, is not connected to the wheels. For example, if you are coasting down a hill, a freewheeling engine will not help slow the car. Why do you ask? ---
**Author:** ![mark9207](https://avatars.discourse-cdn.com/v4/letter/m/71c47a/32.png) [@mark9207](https://community.cartalk.com/u/mark9207)\ **Post date:** [February 8, 2011, 3:36pm UTC](https://community.cartalk.com/t/freewheeling-engine/61058/3 "2011-02-08T15:36:29Z")
Some of the regulars on this forum refer to a non-interference engine design as a “freewheeler”. This would mean that if the timing belt fails, valve damage is not likely to occur. An interference engine, or perhaps “non-freewheeler” is likely to have valve damage in the event of a timing belt failure. Could you tell us where you heard this term and in what context it was used? Right now, we are guessing. ---
**Author:** ![asemaster](https://avatars.discourse-cdn.com/v4/letter/a/5f9b8f/32.png) [@asemaster](https://community.cartalk.com/u/asemaster)\ **Post date:** [February 8, 2011, 3:55pm UTC](https://community.cartalk.com/t/freewheeling-engine/61058/4 "2011-02-08T15:55:40Z")
In your engine there is either a timing belt, a timing chain, or a timing gear set. Essentially, these keep the top half and the bottom half of the engine running in sync. If the belt/chain/gear breaks, the engine quits running. In a freewheeling engine, the top half and bottom half just spin and eventually stop. In a no-freewheeling, ot “interference” engine, the moving parts of the top and bottom (valves and pistons) can hit each other, resulting in major internal engine repair. ---
**Author:** ![texases](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/texases/32/862_2.png) [@texases](https://community.cartalk.com/u/texases)\ **Post date:** [February 8, 2011, 4:43pm UTC](https://community.cartalk.com/t/freewheeling-engine/61058/5 "2011-02-08T16:43:25Z")
Yep, there are two very different meanings for the term. Here’s description related to disengaging the engine: > **[Freewheel](https://en.wikipedia.org/wiki/Freewheel)** > > In mechanical or automotive engineering, a freewheel or overrunning clutch is a device in a transmission that disengages the driveshaft from the driven shaft when the driven shaft rotates faster than the driveshaft. An overdrive is sometimes mistakenly called a freewheel, but is otherwise unrelated. The condition of a driven shaft spinning faster than its driveshaft exists in most bicycles when the rider holds his or her feet still, no longer pushing the pedals. In a fixed-gear bicycle, without a... ---
**Author:** ![aptwoap](https://avatars.discourse-cdn.com/v4/letter/a/c37758/32.png) [@aptwoap](https://community.cartalk.com/u/aptwoap)\ **Post date:** [February 10, 2011, 3:59am UTC](https://community.cartalk.com/t/freewheeling-engine/61058/6 "2011-02-10T03:59:03Z")
Hey Buck-My name is George and I’m the one who asked this question. I’m not a mechanic but I am studying for the ASE P2-Automobile Parts Specialist exam. I liked your answer to my question and I would like to know if you would be available to assist me by answering a few questions from time to time. If so, please email me directly @ [aptwoap@yahoo.com](mailto:aptwoap@yahoo.com). Thanks for your help George Sacramento, Ca ---
**Author:** ![oldschool](https://avatars.discourse-cdn.com/v4/letter/o/e19adc/32.png) [@oldschool](https://community.cartalk.com/u/oldschool)\ **Post date:** [February 10, 2011, 5:10am UTC](https://community.cartalk.com/t/freewheeling-engine/61058/7 "2011-02-10T05:10:18Z")
If you happen to pass the test it probably would be best not to let anyone know about it. Some here equate passing a test with the inability to do real work, for the record I do not happen to feel this way about the ASE’s, good luck.