Well....... it depends
That is kinda like saying how long will a light bulb last.... smile...
The two reasons that you want to overhaul your engines are these....
First we have worn out the parts ... yep this usually never happens unless you are using your plane on a daily basis... and have reached the manufactures time limit on RECOMENDED overhaul... Now if you are using your plane in the states under part 91... and the engine is still making its rated power you can contenue to use it... as the power output is the deciding factor... well kinda..... see we have these bearings and valves that start to go away... and if they (the bearings) get too far gone the soft parts (lead/babbett) are not their anymore... and the next harder backing part (copper)start working on the crank ... which will score it and wear it out... so doing a overhaul will replace the soft part of the bearing... and will save you from having to buy more expensive parts... like cranks.. etc... just to start off...
Now the second reason we overhaul the engines.... is because of RUSTED parts and the time limit on such things as the rubber gaskets... which are under the cyc bases... rocker arm tubes... and the missing seal (silk thread) that makes up the crankcase seal...(no to use other things is not best...)...
So here we have a engine that sits.. never got to see any time in the air... and so it develops condensation and the steel parts start to rust and pit... and yes they do... Cyc that are pitted are big users of oil because as the rings go up the holes or cavities fill with oil... as the rings go down... they pass over these grand canyons' and allow the oil to be exposed to the heat of combustion... and burns off...
but..... that is not all... we have gears and shafts like the accessory shaft that rust and lock the gears on... pit the hardness on the teeth and cause failures...
So to answer your question about how long... the manufacture has specs in the shop manual... and their he says that you should overhaul the engine every so often.. 5 years but, realisticly we see them about every 10years... but again it depends on a lot of things... useage... storage.. and maintance... so all of these are variables that can determine exactly when...
Hoses and flex parts are supposed to be replaced every 5 years ... again that is in the service manual... you do have one...
someone else want to go over what manuals one should have for him... thanks...
Hope this helps.. GMAs
|