Editing Overhead valve engine (section)

=== Predecessors ===
The first internal combustion engines were based on steam engines and therefore used [[slide valve]]s.<ref>{{cite web |title=Part I: V-engines |url=https://www.topspeed.com/cars/engine-s-history-ar11139.html |archive-url=https://archive.today/20200127174925/https://www.topspeed.com/cars/engine-s-history-ar11139.html |url-status=dead |archive-date=January 27, 2020 |website=TopSpeed.com |date=29 July 2006 |access-date=13 December 2019 }}</ref> This was the case for the first [[Otto engine]], which was first successfully run in 1876. As internal combustion engines began to develop separately to steam engines, [[poppet valve]]s became increasingly common.

Beginning with the 1885 [[Daimler Reitwagen]], several cars and motorcycles used inlet valve(s) located in the cylinder head, however these valves were vacuum-actuated ("atmospheric") rather than driven by a camshaft as with typical OHV engines. The exhaust valve(s) were driven by a camshaft, but were located in the engine block as with side-valve engines.

The 1894 [[Diesel engine#The first diesel engine|prototype Diesel engine]] used overhead poppet valves actuated by a [[camshaft]], [[pushrod]]s and [[rocker arm]]s,<ref>{{cite book |last1=Diesel |first1=Rudolf |title=Die Entstehung des Dieselmotors. |date=1913 |publisher=Springer |location=Berlin |isbn=978-3-642-64940-0 |page=17}}</ref><ref>{{cite book |last1=Diesel |first1=Rudolf |title=Theorie und Konstruktion eines rationellen Wärmemotors zum Ersatz der Dampfmaschinen und der heute bekannten Verbrennungsmotoren |date=1893 |publisher=Springer Berlin Heidelberg |location=Berlin |isbn=978-3-642-64949-3 |pages=5,62}}</ref> therefore becoming the first OHV engines. In 1896, U.S. patent 563,140 was taken out by William F. Davis for an OHV engine with liquid coolant used to cool the cylinder head,<ref>{{cite web |url=http://patentimages.storage.googleapis.com/pages/US563140-0.png |title= U.S. patent 563140 |access-date=2017-06-07 |url-status=live |archive-url=https://web.archive.org/web/20170828104245/http://patentimages.storage.googleapis.com/pages/US563140-0.png |archive-date=2017-08-28 }}</ref><ref>{{cite web|url=http://pdfpiw.uspto.gov/.piw?Docid=00563140&homeurl=http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1%2526Sect2=HITOFF%2526d=PALL%2526p=1%2526u=%25252Fnetahtml%25252FPTO%25252Fsrchnum.htm%2526r=1%2526f=G%2526l=50%2526s1=0563,140.PN.%2526OS=PN/0563,140%2526RS=PN/0563,140&PageNum=&Rtype=&SectionNum=&idkey=NONE&Input=View+first+page|title=Patent Images|website=pdfpiw.uspto.gov|access-date=8 May 2018|url-status=dead|archive-url=https://web.archive.org/web/20170828110158/http://pdfpiw.uspto.gov/.piw?Docid=00563140&homeurl=http%3A%2F%2Fpatft.uspto.gov%2Fnetacgi%2Fnph-Parser%3FSect1%3DPTO1%2526Sect2%3DHITOFF%2526d%3DPALL%2526p%3D1%2526u%3D%25252Fnetahtml%25252FPTO%25252Fsrchnum.htm%2526r%3D1%2526f%3DG%2526l%3D50%2526s1%3D0563,140.PN.%2526OS%3DPN%2F0563,140%2526RS%3DPN%2F0563,140&PageNum=&Rtype=&SectionNum=&idkey=NONE&Input=View+first+page|archive-date=28 August 2017}}</ref> but no working model was built.