Contract

EXHIBIT 5.1 SPOLIN SILVERMAN COHEN & BARTLETT, LLP 1620 26th Street, Suite 2000 North Santa Monica, CA 91436 September 9, 2004 Allis-Chalmers Corporation 5075 Westheimer, Suite 890 Houston, Texas 77056 Re: Allis-Chalmers Corporation Registration Statement on Form S-3 Ladies and Gentlemen: At your request, we have examined the Registration Statement on Form S-3 (the "Registration Statement") to which this letter is attached as Exhibit 5.1 filed by Allis-Chalmers Corporation, a Delaware corporation (the "Company"), in order to register under the Securities Act of 1933, as amended (the "Act"), 12,464,760 shares of Common Stock of the Company and any additional shares of Common Stock of the Company which may be registered pursuant to Rule 462(b) under the Act (the "Shares"). The Shares consist of: (i) 8,813,461 shares that were issued to certain investors (identified in the Registration Statement), and (ii) 3,651,299 shares that are issuable to upon the conversion of options and warrants issued to certain investors (identified in the Registration Statement). We have examined originals or certified copies of such corporate records of the Company and other certificates and documents of officials of the Company, public officials and others as we have deemed appropriate for purposes of this letter. We have assumed the genuineness of all signatures, the authenticity of all documents submitted to us as originals, the conformity to authentic original documents of all copies submitted to us as conformed and certified or reproduced copies. Based on the foregoing, we are of the opinion that (a) the 8,813,461 issued and outstanding Shares have been duly authorized, and are validly issued, fully paid and non-assessable, (b) the 3,651,299 Shares that may be issued upon exercise of outstanding options and warrants and other rights, upon issuance and sale in conformity with the agreements and receipt by the Company of the purchase price therefore as specified in the applicable agreements, will be validly issued, fully paid and non-assessable. We consent to the use of this opinion as an Exhibit to the Registration Statement and to use of our name in the prospectus constituting a part thereof. Very truly yours, /S/ SPOLIN SILVERMAN COHEN & BARTLETTT, LLP ------------------------------------------- SPOLIN SILVERMAN COHEN & BARTLETT, LLP