<SEC-DOCUMENT>0001078782-17-000070.txt : 20170113
<SEC-HEADER>0001078782-17-000070.hdr.sgml : 20170113
<ACCEPTANCE-DATETIME>20170113201714
ACCESSION NUMBER:		0001078782-17-000070
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20170111
FILED AS OF DATE:		20170113
DATE AS OF CHANGE:		20170113

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			GENCOR INDUSTRIES INC
		CENTRAL INDEX KEY:			0000064472
		STANDARD INDUSTRIAL CLASSIFICATION:	CONSTRUCTION MACHINERY & EQUIP [3531]
		IRS NUMBER:				590933147
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	BUSINESS ADDRESS:	
		STREET 1:		5201 N ORANGE BLOSSOM TRAIL
		CITY:			ORLANDO
		STATE:			FL
		ZIP:			32810
		BUSINESS PHONE:		4072906000

	MAIL ADDRESS:	
		STREET 1:		5201 N ORANGE BLOSSOM
		CITY:			ORLANDO
		STATE:			FL
		ZIP:			32810

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MECHTRON INTERNATIONAL CORP
		DATE OF NAME CHANGE:	19880128

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MECHTRON GENCO CORP
		DATE OF NAME CHANGE:	19720411

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MECHTRON CORP
		DATE OF NAME CHANGE:	19690909

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Houtkin Sherry
		CENTRAL INDEX KEY:			0001335876

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11703
		FILM NUMBER:		17528936

	MAIL ADDRESS:	
		STREET 1:		3900 ISLAND BLVD.
		STREET 2:		PENTHOUSE 4
		CITY:			AVENTURA
		STATE:			FL
		ZIP:			33160
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-01-11</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000064472</issuerCik>
        <issuerName>GENCOR INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>GENC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001335876</rptOwnerCik>
            <rptOwnerName>Houtkin Sherry</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2295 NW CORPORATE BLVD</rptOwnerStreet1>
            <rptOwnerStreet2>STE 230</rptOwnerStreet2>
            <rptOwnerCity>BOCA RATON</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>33431</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, $.001 par value</value>
            </securityTitle>
            <transactionDate>
                <value>2017-01-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>20000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>15.7691</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1585782</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Excludes 9,036 shares indirectly owned by Ms. Houtkin through Airmont Trust.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Sherry Houtkin</signatureName>
        <signatureDate>2017-01-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
