<PAGE>
                                                                     Exhibit 4.2


                                 AMENDMENT NO. 2

                                       TO

                                 LOAN AGREEMENT
                             DATED DECEMBER 24, 2003
                                 PROVIDING FOR A
                                SECURED TERM LOAN
                              OF UP TO $115,000,000

                         CROWLEY MARINE SERVICES, INC.,
                                  as Borrower,

                                       AND

      The Banks and Financial Institutions listed on Schedule 1 to the Loan
                              Agreement, as Lenders

                                       AND

                                DNB NOR BANK ASA,
                       acting through its New York branch,
                  as Administrative Agent and Security Trustee

                                       AND

                          CROWLEY MARITIME CORPORATION,
                                  as Guarantor

                                  June 30, 2004



                        AMENDMENT NO. 2 TO LOAN AGREEMENT

            THIS AMENDMENT NO. 2 TO LOAN AGREEMENT (this "Amendment") is made as
of the 30th day of June, 2004 by and among (i) CROWLEY MARINE SERVICES, INC., a
corporation organized and existing under the laws of the State of Delaware (the
"Borrower"), (ii) CROWLEY MARITIME CORPORATION, a corporation organized and
existing under the laws of the State of Delaware, as guarantor (the "Guarantor"
and together with
<PAGE>
the Borrower, the "Loan Parties"), (iii) the banks and financial institutions
whose names and addresses are set out in Schedule 1 to the Loan Agreement
(together with any assignee pursuant to Section 9.07 of the Loan Agreement, the
"Lenders", and each a "Lender"), (iv) DnB NOR Bank ASA (formerly known as Den
norske Bank ASA), acting through its New York branch, as administrative agent
for the Lenders (in such capacity the "Administrative Agent") and as security
trustee for the Lenders (in such capacity the "Security Trustee"), and amends
and is supplemental to the Loan Agreement dated December 24, 2003, as amended by
that certain Amendment No. 1 to Loan Agreement dated as of March 15, 2004, made
by and among (1) the Borrower, (2) the Guarantor, (3) the Lenders, (4) the
Administrative Agent and (5) the Security Trustee (collectively, the "Loan
Agreement").

                                WITNESSETH THAT:

            WHEREAS, pursuant to the Loan Agreement, the Lenders made available
to the Borrower a secured term loan in the amount of up to U.S.$115,000,000 (the
"Loan") the proceeds of which were utilized as provided therein;

            WHEREAS, the Loan Parties have requested, and the Lenders have
agreed to amend certain provisions of the Loan Agreement as set forth herein;

            NOW, THEREFORE, in consideration of the premises and such other good
and valuable consideration, the receipt and adequacy of which are hereby
acknowledged by the parties, it is hereby agreed as follows:

            1. Definitions. Unless otherwise defined herein, words and
expressions defined in the Loan Agreement shall bear the same meanings when used
herein.

            2. Representations and Warranties. Each of the Loan Parties hereby
reaffirms, as of the date hereof, each and every representation and warranty
made thereby in the Loan Agreement, the Note and the Security Documents (updated
mutatis mutandis).


            3. No Defaults. Each of the Loan Parties hereby represents and
warrants that as of the date hereof there exists no Event of Default or any
condition which, with the giving of notice or passage of time, or both, would
constitute an Event of Default.

            4. Performance of Covenants. Each of the Loan Parties hereby
reaffirms that it has duly performed and observed the covenants and undertakings
set forth in the Loan Agreement and the Security Documents to which it is a
party, on its part to be performed, and covenants and undertakes to continue to
duly perform and observe such covenants and undertakings, as amended hereby, so
long as the Loan Agreement shall remain in effect.

            5. Amendment to the Loan Agreement. Subject to the terms and
conditions of this Amendment, the Loan Agreement is hereby amended and
supplemented as follows:

(a)   Section 1.1 is amended by inserting the following definition of "EBITDAR"
      immediately following the definition of "EBITDA" and before the definition
      of "Eligible Assistance":


                                       2
<PAGE>
                        ""EBITDAR" means the operating income plus the sum of
                        (a) depreciation expense, (b) amortization expense and
                        (c) rent or lease expense (reduced by an amount equal to
                        25% of the first year of time charter commitments used
                        in the Total Debt calculation), in each case, as
                        reflected in the "Consolidated Statement of Operations"
                        of CMC prepared in accordance with GAAP; provided that
                        EBITDAR shall be calculated on a rolling basis for the
                        four fiscal quarters most recently ended."

(b)   Section 1.1 is further amended by inserting the following definition of
      "Total Debt" immediately following the definition of "Title XI
      Subsidiaries" and before the definition of "Vessels":

                        ""Total Debt" means, as to CMC and its Consolidated
                        Subsidiaries at any time, the aggregate sum of (a) all
                        Indebtedness (as reflected on the Consolidated balance
                        sheet of CMC), (b) future lease commitments (as such
                        future lease commitments are presented in CMC's most
                        recent annual consolidated financial statements that are
                        available at the end of the period delivered to the
                        Lenders pursuant to Section 5.01(a)(i) or in such other
                        statement or report that is publicly disclosed)
                        discounted at a rate of 10% and (c) all Guaranty
                        Obligations valued at the full amount of the underlying
                        obligation (as reflected in the footnote to the
                        consolidated balance sheet of CMC) and other contingent
                        liabilities. For purposes of calculating Total Debt, the
                        total future payments under leases constituting time
                        charters, to be reported by the CMC pursuant to Section
                        5.01(a), shall be reduced by 25% prior to application of
                        the discount referred to in clause (b) above."

(c)   Section 5.03(a) is amended and restated in its entirety as follows:

                        "(a) Total Debt to EBITDAR Ratio. Maintain, at the end
                        of each fiscal quarter of the Guarantor, a ratio of
                        Total Debt to EBITDAR for the four fiscal quarters ended
                        as of the end of such quarter not greater than the ratio
                        set forth below for each period set forth below:

<TABLE>
<CAPTION>
                     ------------------------------------------
                       FOR EACH FISCAL
                     QUARTER DURING THE      TOTAL DEBT/EBITDAR
                     FISCAL YEAR ENDING            RATIO
                         DECEMBER 31
                     ------------------------------------------
<S>                                          <C>
                            2004                 3.25:1.00
                     ------------------------------------------
                            2005                 3.25:1.00
                     ------------------------------------------
                     2006 and thereafter         3.00:1.00
                     ------------------------------------------
</TABLE>


                                       3
<PAGE>
(d)   Section 5.03(c) is amended and restated in its entirety as follows:

                        "(c) Consolidated Net Worth. Maintain a Consolidated Net
                        Worth, as measured at the end of each fiscal quarter, in
                        an amount not less than the sum of One Hundred and
                        Seventy Five Million Dollars ($175,000,000) plus 25% of
                        all positive net income of CMC (on a consolidated basis)
                        earned after December 31, 2003 plus 50% of all net
                        proceeds from the sale of any equity interest in the
                        Guarantor or any of the Subsidiaries to any Person other
                        than the Guarantor or any of the Subsidiaries."

            6. No Other Amendment. All other terms and conditions of the Loan
Agreement shall remain in full force and effect and the Loan Agreement shall be
read and construed as if the terms of this Amendment were included therein by
way of addition or substitution, as the case may be.

            7. Other Documents. By the execution and delivery of this Amendment,
the Loan Parties hereby consent and agree that all references in the Note and
the Security Documents to the Loan Agreement shall be deemed to refer to the
Loan Agreement as further amended by this Amendment.

            8. Governing Law. This Amendment shall be governed by and construed
in accordance with the laws of the State of New York.

            9. Counterparts. This Amendment may be executed in as many
counterparts as may be deemed necessary or convenient, and by the different
parties hereto on separate counterparts each of which, when so executed, shall
be deemed to be an original but all such counterparts shall constitute but one
and the same agreement.

            10. Headings; Amendment. In this Amendment, Section headings are
inserted for convenience of reference only and shall be ignored in the
interpretation of this Amendment. This agreement cannot be amended other than by
written agreement signed by the parties hereto.


                                       4
<PAGE>
IN WITNESS WHEREOF, each of the parties hereto has executed this Amendment by
its duly authorized representative on the day and year first above written.

                                    CROWLEY MARINE SERVICES, INC.,
                                    as Borrower


                                    By /s/ Albert M. Marucco
                                       ---------------------
                                       Name: Albert M. Marucco
                                       Title: Vice President and Treasurer


                                    CROWLEY MARITIME CORPORATION,
                                    as Guarantor


                                    By /s/ Albert M. Marucco
                                       ---------------------
                                       Name: Albert M. Marucco
                                       Title: Vice President and Treasurer


                                    DNB NOR BANK ASA, acting through its New
                                    York Branch, as Administrative Agent,
                                    Security Trustee and Lender


                                    By /s/ Barbara Gronquist
                                       ---------------------
                                       Name: Barbara Gronquist
                                       Title: Senior Vice President


                                    By /s/ Nikolai A. Nachamkin
                                       ------------------------
                                       Name: Nikolai A. Nachamkin
                                       Title: First Vice President


                                       5
<PAGE>
                                    DVB BANK AG
                                    as  Lender


                                    By /s/ Gorm Eikemo
                                       ---------------
                                       Name: Gorm Eikemo
                                       Title: VP


                                    By /s/ Richard E. Jansen
                                       ---------------------
                                       Name: Richard E. Jansen
                                       Title: VP


                                    RBS LOMBARD, INC.
                                    as  Lender


                                    By /s/ Maureen Carr
                                       ------------------
                                       Name: Maureen Carr
                                       Title: V.P.


                                    FORTIS CAPITAL CORP.
                                    as  Lender


                                    By /s/ Svein Engh
                                       ----------------
                                       Name: Svein Engh
                                       Title: Managing Director


                                    By /s/ Chr.Tobias Backer
                                       ---------------------
                                       Name: Chr.Tobias Backer
                                       Title: Vice President


                                       6
<PAGE>
                                    NORDEA BANK NORGE ASA,
                                    GRAND CAYMAN BRANCH
                                    as  Lender



                                    By /s/ Hans Chr. Kjelsrud
                                       ----------------------
                                       Name: Hans Chr. Kjelsrud
                                       Title: Senior Vice President



                                    By /s/ Alison B. Barber
                                       --------------------
                                       Name: Alison B. Barber
                                       Title: Vice President


                                       7