Exhibit 5.1

[Skadden Letterhead]

May 6, 2013

Crane Co.

100 First Stamford Place

Stamford, Connecticut 06902

Re:    Crane Co.                     Registration Statement on Form S-3

Ladies and Gentlemen:

We have acted as special counsel to Crane Co., a Delaware corporation (the "Company"), in connection with the Registration Statement on Form S-3 (the "Registration Statement"), to be filed on the date hereof by the Company with the U.S. Securities and Exchange Commission (the "Commission") under the Securities Act of 1933, as amended (the "Act"). The Registration Statement relates to the issuance and sale from time to time by the Company, pursuant to Rule 415 of the General Rules and Regulations promulgated under the Act, of the senior or subordinated debt securities of the Company, in one or more series (the "Debt Securities"), which may be issued under the Indenture (the "Senior Indenture"), proposed to be entered into between the Company and a trustee to be named therein, and the Subordinated Debt Indenture (the "Subordinated Indenture"), proposed to be entered into between the Company and a trustee to be named therein (collectively, the "Indentures" and each trustee, a "Trustee").

This opinion is being delivered in accordance with the requirements of Item 601(b)(5) of Regulation S-K adopted under the Act.

In connection with this opinion, we have examined originals or copies, certified or otherwise identified to our satisfaction, of:

Crane Co.

May 6, 2013

(i)    the Registration Statement relating to the Debt Securities;

(ii) the form of Senior Indenture, to be filed as Exhibit 4.1 to the Registration Statement; and

(iii) the form of Subordinated Indenture, to be filed as Exhibit 4.2 to the Registration Statement.

We have also examined originals or copies, certified or otherwise identified to our satisfaction, of such records of the Company and such agreements, certificates and receipts of public officials, certificates of officers or other representatives of the Company and others, and such other documents, certificates and records as we have deemed necessary or appropriate as a basis for the opinions set forth herein.

In our examination, we have assumed the legal capacity and competency of all natural persons, the genuineness of all signatures, including endorsements, the authenticity of all documents submitted to us as originals, the conformity to original documents of all documents submitted to us as facsimile, electronic, certified, conformed or photostatic copies and the authenticity of the originals of such copies. As to any facts material to the opinions expressed herein which were not independently established or verified, we have relied upon oral or written statements and representations of officers and other representatives of the Company and others and of public officials. In making our examination of documents executed or to be executed, we have assumed that the parties thereto, other than the Company, had or will have the power, corporate or other, to enter into and perform all obligations thereunder and have also assumed the due authorization by all requisite action, corporate or other, and execution and delivery by such parties of such documents and the validity and binding effect thereof on such parties. We have assumed that each of the Indentures will be duly authorized, executed and delivered by the Trustee, in substantially the forms reviewed by us, and that any Debt Securities that may be issued will be manually authenticated, signed or countersigned, as the case may be, by duly authorized officers of the Trustee. We have assumed that the choice of New York law to govern the Debt Securities and the Indentures and any supplemental indentures thereto is a valid and legal provision. In addition, we have also assumed that the terms of the Debt Securities will have been established so as not to, and that the execution and delivery by the Company of, and the performance of its obligations under, the Indentures, any supplemental indentures thereto and the Debt Securities will not, violate, conflict with or constitute a default under (i) any agreement or instrument to which the Company or its properties is subject, (ii) any law, rule or regulation to which the Company or its properties is subject, (iii) any judicial, administrative or regulatory order or decree of any governmental authority or (iv) any consent, approval, license, authorization or validation of, or filing, recording or registration with any governmental authority.

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Crane Co.

May 6, 2013

Our opinions set forth below are limited to the laws of the State of New York that, in our experience, are normally applicable to debt securities of the type covered by the Registration Statement and to the extent that judicial or regulatory orders or decrees or consents, approvals, licenses, authorizations, validations, filings, recordings or registrations with governmental authorities are relevant, to those required under such laws (all of the foregoing being referred to as "Opined on Law"). We do not express any opinion with respect to the law of any jurisdiction other than Opined on Law or as to the effect of any such non-Opined on Law on the opinions herein stated. The Debt Securities may be issued from time to time on a delayed or continuous basis, and this opinion is limited to the laws, including the rules and regulations, as in effect on the date hereof, which laws are subject to change with possible retroactive effect.

Based upon and subject to the foregoing and to the limitations, qualifications, exceptions and assumptions set forth herein, we are of the opinion that with respect to any series of Debt Securities (the "Offered Debt Securities"), when (i) an appropriate prospectus supplement with respect to the Offered Debt Securities has been prepared, delivered and filed in compliance with the Act and the applicable rules and regulations thereunder; (ii) if the Offered Debt Securities are to be sold pursuant to a firm commitment underwritten offering, the underwriting agreement with respect to the Offered Debt Securities has been duly authorized, executed and delivered by the Company and the other parties thereto; (iii) the Board of Directors of the Company, including any appropriate committee appointed thereby, and appropriate officers of the Company have taken all necessary corporate action to approve the issuance and terms of the Offered Debt Securities and related matters; (iv) the terms of the Offered Debt Securities and of their issuance and sale have been duly established in conformity with the applicable Indenture and any supplemental indenture to be entered into in connection with the issuance of such Offered Debt Securities so as not to violate any applicable law, the Certificate of Incorporation of the Company, as amended and currently in effect (the "Certificate of Incorporation") or the By-Laws of the Company, as amended (the "Bylaws"), or result in a default under or breach of any agreement or instrument binding upon the Company and so as to comply with any requirement or restriction imposed by any court or governmental body having jurisdiction over the Company; and (v) the Offered Debt Securities, in the form to be filed on a Current Report on Form 8-K or other applicable periodic report, have been duly executed and authenticated in accordance with the provisions of the applicable Indenture and any supplemental indenture relating to the Offered Debt Securities and have been duly delivered to the purchasers thereof upon payment of the agreed-upon consideration therefor, the Offered Debt Securities, when issued and sold in accordance with the applicable Indenture and any supplemental indenture relating to the Offered Debt Securities and any officers' certificate or board resolution adopted in connection with the issuance of such Offered Debt Securities and the applicable underwriting agreement, if any, or any other duly authorized, executed and delivered valid and binding purchase or agency agreement, will be valid and binding obligations of the Company, enforceable against the Company in

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Crane Co.

May 6, 2013

accordance with their respective terms under the laws of the State of New York, except to the extent that enforcement thereof may be limited by (a) bankruptcy, insolvency, reorganization, fraudulent conveyance, moratorium or other similar laws now or hereafter in effect relating to creditors' rights generally, (b) general principles of equity (regardless of whether enforceability is considered in a proceeding at law or in equity), (c) public policy considerations which may limit the rights of parties to obtain remedies and (d) waivers of any usury defense contained in the Indentures, any supplemental indenture or the Offered Debt Securities which may be unenforceable.

We hereby consent to the filing of this opinion with the Commission as an exhibit to the Registration Statement. We also hereby consent to the use of our name under the heading "Legal Matters" in the prospectus which forms a part of the Registration Statement. In giving this consent, we do not thereby admit that we are within the category of persons whose consent is required under Section 7 of the Act or the rules and regulations of the Commission promulgated thereunder. This opinion is expressed as of the date hereof unless otherwise expressly stated, and we disclaim any undertaking to advise you of any subsequent changes in the facts stated or assumed herein or of any subsequent changes in applicable laws.

Very truly yours,

/s/ Skadden, Arps, Slate, Meagher & Flom LLP

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