ID: nht75-3.28

DATE: 11/24/75

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: The Cleveland Electric Illuminating Co.

COPYEE: ROBERT E. WELTZER -- HWY. SAFETY MGMT. SPECIALIST, REGION V

TITLE: FMVSR INTERPRETATION

TEXT: This is in further response to your letter of June 11, 1975, to Mr. Kenneth Bowman, Area Director, Cleveland, Ohio, concerning the legal responsibilities of a person who modifies a motor vehicle.

IMPACT OF FEDERAL LAW

A person who performs work on a vehicle prior to the first purchase of the vehicle in good faith for purposes other than resale may be subject to the regulations of the National Highway Traffic Safety Administration (NHTSA) either as an alterer of a completed vehicle or as a final-stage manufacturer of an incomplete vehicle. A vehicle is "complete" only if it bears a certification label stating conformity to all applicable Federal regulations.

In addition, the National Traffic and Motor Vehicle Safety Act provides that

"No manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative, in whole or in part, any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard." (Sec. 108(a)(2)(A), Pub. L. 93-492, 88 Stat. 1470; 15 U.S.C. @ 1397(a)(2)(A))

This prohibition applies both before and after the first purchase of a motor vehicle, but does not apply to work performed on a vehicle by the individual owner of the vehicle. In addition, exceptions are provided to permit the rendering inoperative of safety belt interlocks and continuous buzzers after first purchase of the vehicle, and in certain circumstances just before first purchase.

VEHICLE ALTERATION

The regulations of the NHTSA cover two types of vehicle alterations. The first is an alteration of a completed vehicle by the addition, substitution, or removal of readily attachable components such as mirrors or tire and rim assemblies, or minor finishing operations such as painting which do not alter the vehicle's stated weight rating (49 CFR @ 567.6). This type of alteration does not involve any additional responsibilities by the alterer.

The second type of alteration is an alteration of a certified vehicle by means other than the addition, substitution, or removal of readily attachable components or minor finishing operations, or alteration in such a manner that the vehicle's stated weight ratings are no longer valid (49 CFR @ 567.7). This type of alteration, if done prior to the first purchase of the vehicle for purposes other than resale, must include, in addition to the certification label, a label stating that the vehicle as altered conforms to all applicable Federal motor vehicle safety standards and containing the firm or individual name of the alterer (49 CFR @ 567.7).

COMPLETION OF VEHICLE MANUFACTURE

If a vehicle (such as a chassis-cab) requires further manufacturing operations in order to become a completed vehicle, the completion of the vehicle constitutes final manufacture and necessitates compliance with the certification requirements of 49 CFR @@ 567.5 and 568.6. The name of the finalstage manufacturer must appear on the certification label as the manufacturer, unless the incomplete vehicle manufacturer assumes legal responsibility for the vehicle as finally manufactured (49 CFR @@ 567.5, 568.6 and 568.7).

To aid the final-stage manufacturer, the incomplete vehicle manufacturer is required to furnish with the incomplete vehicle a statement including the weight ratings of the vehicle if completed as intended, descriptions of the Federal motor vehicle safety standards applicable to the vehicle, and the conditions under which final completion of the vehicle will comply with such standards (49 CFR @ 568.4). If the final-stage manufacturer follows these instructions and conditions, the liability for non-compliance with a safety standard will be on the incomplete vehicle manufacturer. Although the certification requirements may be modified as a result of litigation, the NHTSA will consider compliance with the published requirements to meet any manufacturer's responsibilities under the National Traffic and Motor Vehicle Safety Act (15 U.S.C. @ 1403 et seq.).

Final-stage manufacturers are also subject to the manufacturer identification rules of 49 CFR @ 566, which require manufacturers to submit to the NHTSA identifying information and descriptions of the items they produce. A final-stage manufacturer may also be subject to the defect reporting requirements of 49 CFR @ 573, which concern a manufacturer's responsibilities to report safety-related defects.

Enclosed are copies of section 108 of the National Traffic and Motor Vehicle Safety Act, and Parts 566, 567, 568 and 573 of the NHTSA's regulations. In addition, we are enclosing a copy of "Standards", a summary description of the Federal motor vehicle safety standards.

If you have any questions concerning the foregoing regulations or any Federal motor vehicle safety standard, we suggest that you write

Chief Counsel National Highway Traffic Safety Administration 400 Seventh Street, S.W. Washington, D.C. 20590

We hope that this information has been of assistance.

Yours truly,

Enclosures

ID: nht75-3.29

DATE: 10/22/75

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Koher Company

COPYEE: SENATOR PROXMIRE

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of September 29, 1975, to Senator Proxmire, concerning the regulations governing the production of motor vehicles, a copy of which was referred to this office.

The National Highway Traffic Safety Administration (NHTSA) issues Federal motor vehicle safety standards to which motor vehicles must conform. In addition, the agency requires that the manufacturer certify that the vehicle as completed complies with applicable safety standards. A pamphlet summarizing the Federal motor vehicle safety standards is enclosed, along with a copy of the regulations governing vehicle certification. The safety standards themselves are set forth in their entirety in Part 571 of Volume 49 of the Code of Federal Regulations.

The NHTSA also investigates safety-related defects and noncompliances with safety standards in motor vehicles and items of motor vehicle equipment. If the agency or the manufacturer determine that a safety-related defect or noncompliance exists, the manufacturer is obligated to notify the vehicle owners and remedy the problem without charge. A copy of the provisions of the National Traffic and Motor Vehicle Safety Act of 1966, as amended, which deal with the responsibilities of manufacturers for safety-related defects and noncompliances in their motor vehicles or item of vehicle equipment (15 U.S.C. @ 1411-1420) is also enclosed.

If you have any questions concerning a specific regulation or standard, please write.

United States Senate 10/7/75

To ensure proper handling please return all correspondence TO THE ATTENTION OF:

Geri Rosen

Respectfully referred to: Cong. Liaison DOT

Please respond to the attached inquiry in duplicate and return the enclosure. Thank you for your cooperation. (Illegible Word) U.S.S.

September 24, 1975

DEAR SENATOR:

Kohler Co. is investigating what would be involved in going into production on a very small, very fuel efficient, low-cost urban car suitable for shopping and commuting. We know there are several government agencies that have regulations controlling how you build a vehicle but we do not know what those regulations are or even what agencies we would have to contact. It is vitally important that we know all the regulations and wondered if you know some way we can obtain a copy of all the regulations from all the controlling bureaus. We would certainly appreciate your help in this quest.

YOURS TRULY,

Daniel J. Wahlen Director - Engines Engineering -- KOHLER CO.

Senator William Proxmire

ID: nht75-3.3

DATE: 10/22/75

FROM: AUTHOR UNAVAILABLE; R. B. Dyson; NHTSA

TO: Nissan Motor Company

TITLE: FMVSS INTERPRETATION

TEXT: This is in reply to your letter of September 8, 1975, to Mr. Berndt requesting an interpretation of the visibility requirements specified in paragraph S4.3.1.1 of Federal Motor Vehicle Safety Standard No. 108.

Specifically, you ask whether a front turn signal lamp which is partially obscured by the radiator grille as shown on a drawing that you enclosed would meet the specified visibility requirements, if . . .

"1. The lamp met the photometric requirements under the state of being equipped on the vehicle.

2. We could easily observe through all the photometric test angles that the lamp was activated."

If condition 1 above is met, the lamp would appear to comply with the visibility requirements of paragraph S4.3.1.1.

For condition 2 above, SAE Standard J588d, incorporated by reference in Standard No. 108, specifies in part that signals from lamps mounted on the left and right sides of the vehicle shall be visible through a horizontal angle of 45 degrees to the left and right respectively. To be considered visible, the lamp must provide an unobstructed projected illuminated area of outer lens surface, excluding that portion of the lens that may serve as a reflex reflector, at least 2 square inches in extent, measured at 45 degrees to the longitudinal axis of the vehicle. If your design meets the specified requirement, the lamp would also be in compliance with the requirements of paragraph S4.3.1.1.

As you were informed in a meeting with Messrs. Leysath and Vinson of this agency on September 8, 1975, it is not necessary that the entire lamp as partially obscured comply with Standard No. 108. If either the upper or lower portion of the lamp meets the photometric and visibility requirements, that is sufficient for conformance. If certification is based upon the lower portion alone, however, the center of the lower portion must be mounted not less than 15 inches above the pavement.

Yours truly,

September 8, 1975

Frank Berndt -- Chief Council, National Highway Traffic Safety Administration

Dear Mr. Berndt: This is to ask your interpretation regarding the visibility requirement stated in S 4.3.1.1 of FMVSS 108.

In the case of the turn signal lamp, installation requirements of SAE J5882 referred to FMVSS 108, states:

When one turn signal is used on each side of the front and rear, visibility of the front signal to front and the rear signal to the rear shall not be obstructed by any part of the vehicle throughout the photometric test angles for the lamp.

Even if a part of the turn signal lamp is covered with the radiator grill as shown in the attached drawing, may we understand under the following conditions that the turn signal lamp meets the visibility requirement?

1. The lamp met the photometric requirement under the state of being equipped on the vehicle.

2. We could easily observe through all the photometric test angles that the lamp was activated.

Your prompt reply to this matter would be greatly appreciated.

Very truly yours,

NISSAN MOTOR CO., LTD. -- Tokio Iinuma, Staff, Safety

Attachment

(Graphics omitted)

ID: nht75-3.30

DATE: 06/06/75

FROM: AUTHOR UNAVAILABLE; Richard B. Dyson; NHTSA

TO: Mr. John M. Burlake

TITLE: FMVSR INTERPRETATION

TEXT: This is in response to your letter of April 8, 1975, requesting information concerning the compliance of the seat belt assembly of a 1972 BMW sedan.

Manufacturers of motor vehicles are required by section 114 of the National Traffic and Motor Vehicle Safety Act (Pub. L. 89-563) to affix permanently to their vehicles a certification label that confirms each vehicle's compliance with all applicable Federal motor vehicle safety standards. 49 CFR Parts 567 and 568 detail the procedure for satisfying the certification requirement. Manufacturers are not required to furnish the Department with a certification statement.

There are three motor vehicle safety standards that relate to the seat belt assembly. Depending upon the date of manufacture of the BMW in question, it should have been certified as complying with the standards that were in effect at that time.

The National Highway Traffic Safety Administration's Office of Defects Investigation maintains a log of reported defects in motor vehicles or motor vehicle equipment. Therefore, if you wish to ascertain whether or not there have been similar reports of seat belt assembly defects in certain 1972 BMW models, I suggest you write to that office enclosing full information on the nature of the alleged defect and the vehicle model. You may also be interested in obtaining information pursuant to the procedure described in the enclosed Federal Register notice.

ID: nht75-3.31

DATE: 03/25/75

FROM: AUTHOR UNAVAILABLE; James C. Schultz; NHTSA

TO: New York Department of Transportation

TITLE: FMVSR INTERPRETATION

ID: nht75-3.32

DATE: 05/22/75

FROM: AUTHOR UNAVAILABLE; James B. Gregory; NHTSA

TO: Aslan Truck Service

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of April 15, 1975, explaining your reasons for not purchasing bulk agricultural commodity trailers that conform to the requirements of Standard No. 121, Air brake systems. You said that you expect that the new systems will be disabled or destroyed by rough usage in the fields, and that you intend to manufacture trailers that do not conform to the standard.

We have no reason to believe that the new axle systems will be more susceptible to field hazards than are present systems. Most antilock systems are designed so that the outboard sensor is enclosed in the hub and the wiring harness is routed inside the axle to the antilock module. There are antilock systems that incorporate the antilock module and air valve in the same location as the relay valve found on pre-121 vehicles. We therefore expect little change in the susceptibility of these vehicles to field hazards.

You stated that you intend to manufacture air-braked trailers for your own use which do not comply with Standard No. 121. The National Traffic and Motor Vehicle Safety Act (15 U.S.C. 1391, et seq.) prohibits the manufacture of non-complying vehicles after the effective date of an applicable standard as follows:

@ 1397 (a) (1) No person shall --

(A) manufacture for sale, sell, offer for sale, or introduce or deliver for introduction in interstate commerce, or import into the United States, any motor vehicle or item of motor vehicle equipment manufactured on or after the date any applicable Federal motor vehicle safety standard takes effect under this subchapter unless it is in conformity with such standard except as provided in subsection (b) of this section; . . .

From your description, your plans to build vehicles which would subsequently be introduced in interstate commerce (i.e., driven on the public highway) would appear to be in violation of this section. Civil penalties of up to $ 1,000 per violation can be assessed under @ 1398 of the Act.

I am interested in hearing from you on your experience with Standard No. 121 if you choose to purchase any complying vehicles. In any case, I would like to assure you that the National Highway Traffic Safety Administration (NHTSA) is in the process of monitoring the standard's economic impact. The NHTSA will attempt to identify any modifications that would lower the standard's cost while achieving comparable levels of safety.

SINCERELY,

April 15, 1975

James B. Gregory, Administrator U.S. Dept. of Transportation National Highway Traffic Safety Administration

Received your letter of March 31, 1975, in regards to the Standard No. 121, Air brake System.

I understand very well your reasons for denying my request for exempting agriculture trailers from the new brake law No. 121. It is impossible for us to comply with the new regulations. We see nothing but trouble with them in the fields, after we have dropped them to the roadside of the ranches where the farmer is harvesting. He will drag them through the field with his own farm tractor, which has no air. He will pull them over weeds, tomato vines, grain fields and many other types of field harvesting in plowed ground. Our feeling is that it will create nothing but trouble with the brakes locking and not working.

I have two hundred and fifty bulk agriculture trailers in the field during harvest season, and I do not have the time and the extra help to keep these trailers in working order if the brakes lock up. With our present trailers we do not have any trouble of any sort and that is the way we are going to continue to operate.

We had an order, for the 1975 season, 100 more new trailers to be able to meet the volume of the additional acreages that are being planted this year. Unfortunatly, we had to cancel our order and are buying as many of 1973-74 trailers that we can find and what we cannot find we will build ourselves.

You said that the major concern is that these trailers could be used in the winter months. It is impossible for us to use these bulk trailers for anything other than bulk harvesting. There are no floors, no stake pockets and the fiberglass bulk tanks cannot haul anything else but raw food products, which are grown and harvested during the May, June, July, August, September, October, and November months.

In regard to the petition filed by Utility Trailer Co., our opinion is that all of the Anti-Skid Standard No. 121 brake law should be excluded from the 1975 harvest season so the manufactures can have one year to try it in various localities to see if it will work satisfactory. Otherwise, I do not believe any of the truckers, including myself, will be interested in buying any trailers that are not guaranteed to be trouble free.

Our company, which happens to be one of the largest bulk haulers in California, will not buy or use any trailers with the new 1975 Standard No. 121 brake system. Up until the time it can be proven to me that it will be absolutaly trouble free, we do not dare to take the chance. I sure do not want to invest an extra one hundred and fifty thousand dollars to find out; our costs are high enough now.

A. L. Aslan

ASIAN TRUCK SERVICE

ID: nht75-3.33

DATE: 12/15/75

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Volvo of America Corporation

TITLE: FMVSS INTERPRETATION

TEXT: This responds to Volvo of America's October 9, 1975, question whether a truck equipped with an air-assisted hydraulic brake system with hydraulic push through capability and, in the towing vehicle configuration, a source of compressed air for air braked trailer operation, is subject to Standard No. 121, Air Brake Systems.

From your description of the system and the materials that accompanied your letter, the truck does not qualify as an air-braked vehicle to which the standard applies. The fact that it is capable of operation in combination with an air-braked vehicle and supplies the compressed air for braking that vehicle does not affect the truck's classification as an hydraulic-braked vehicle.

At the time Standard No. 121 was developed, it covered virtually all of the trucks and truck-tractors in the heaviest categories. In planning and making your decisions to introduce hydraulic-braked vehicles in these weight categories, you should be aware that this agency is planning to cover all such vehicles with the basic performance requirements presently contained in Standard No. 121.

SINCERELY,

October 9, 1975

Frank Berndt, Acting Chief Counsel National Highway Traffic Safety Administration

Re: Applicability of Brake Regulations to Vehicle Combinations Consisting of a Hydraulic Brake Equipped Tractor and an Air Brake Equipped Trailer.

Volvo of America Corporation is currently considering the importation of a hydraulic brake equipped truck with a GVWR of 29,000 pounds. The basic vehicle can be outfitted as either a straight truck or a truck tractor. Both versions employ the same brake system. Our question concerns the applicability of the requirements of FMVSS No. 121 to this truck tractor when coupled to an air brake equipped trailer.

The operating principles of the brake system employed on both versions of the truck are described in the attachments to this letter. Basically it is an air assisted hydraulic brake system with a hydraulic push through capability. In the tractor version of this truck provisions are made in the brake system for the supply of compressed air to the brake system of the attached trailer. This is accomplished in a manner which enables the truck to operate in combination with conventional air brake equipped trailers.

Our understanding of the pertinent regulations indicates that since the truck tractor is not subject to the requirements of FMVSS No. 121, being fitted with hydraulic brakes, the combination of this tractor and an air brake equipped trailer also is not subject to the requirements of FMVSS No. 121, regardless of what requirements are applicable to the trailer by itself. Your verification of this understanding is requested.

Your prompt consideration of this matter would be greatly appreciated. If you have any questions concerning the technical details of the brake system, please direct them to Mr. Bjorn Klingenberg at the address indicated below:

Volvo of America Corporation Truck Division 266 UNION STREET NORTHVALE, N.J. 07647

All other communications concerning this matter should be directed to the undersigned.

VOLVO OF AMERICA CORPORATION Product Engineering and Development

Donald W. Taylor Manager, Product Safety & Quality

CC: B. KLINGENBERG

ID: nht75-3.34

DATE: 09/29/75

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Arent, Fox, Kintner, Plotkin & Kahn

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your September 23, 1975, request for confirmation that a manufacturer of air-braked buses that conform to Standard No. 121, Air Brake Systems, may direct owners of these vehicles to disconnect the antilock system used to meet the standard, for the period necessary to correct a safety-related defect in the system that may make its operation hazardous. Your concern is with S 108(a) (2) (A) of the National Traffic and Motor Vehicle Safety Act (15 U.S.C. S 1397(a) (2) (A)) that states:

S 1397 * * *

(2) (A) No manufacturer, distributor, dealer, or motor vehicle repair business shall knowingly render inoperative, in whole or part, any device or element of design installed on or in a motor vehicle or item of motor vehicle equipment in compliance with an applicable Federal motor vehicle safety standard * * *

Section 108(a) (2) (A) prohibits, with one exception, the knowing disconnection of the antilock system by a manufacturer, distributor, dealer, or motor vehicle repair business. This prohibition does not prevent an owner of air-braked buses from disconnection of the antilock system. The NHTSA has determined that a manufacturer of air-braked buses that conform to Standard No. 121 may instruct the owners of its products to disconnect the antilock system used to meet the standard, for the period necessary to correct a safety-related defect in the system that may make its operation hazardous.

A manufacturer that has determined the existence of a safety-related defect in his vehicle must, of course, comply with the Defect Report requirements of 49 CFR Part 573 and the Defect Notification requirements of 49 CFR Part 577.

SINCERELY,

ARENT, FOX, KINTNER, PLOTKIN & KAHN

September 23, 1975

Richard B. Dyson Office of the Chief Counsel National Highway Traffic Safety Admininstration

Pursuant to our telephone conversation of today, we are requesting your advice relative to a matter under the National Traffic & Motor Vehicle Safety Act. Our client, Rohr Industries, Flexible Division, manufactures buses on which are installed air brake systems which comply with 49 C.F.R. S 571.121 (Standard No. 121), skid control systems. Recently four Standard No. 121 systems which are manufactured by Rockwell International Corporation, have malperformed during the operation of a bus by a municipal customer of Rohr Industries. As the possible failure of the Standard No. 121 system presents a potential danger to the public, our client would like to take corrective action at the earliest possible time.

Rockwell International has indicated that a corrective device to prevent malfunctions in its Standard No. 121 system may be available for installation in November of 1975. It is our understanding that a manufacturer can, within the requirements of the National Traffic & Motor Vehicle Safety Act, direct its customers to disconnect the defective system until a correction to the system is available. It is requested that you confirm that our client, Rohr Industries, can in this situation, within the provisions of the National Traffic & Motor Vehicle Safety Act, direct its customers to disconnect the Standard No. 121 system until such time as Rockwell International has made available corrective equipment.

In order to implement this action which will remove a potentially unsafe situation, your confirmation is requested as soon as practicable. Your cooperation is greatly appreciated.

Joseph E. Casson

CC: FRANK FERRONE

ID: nht75-3.35

DATE: 09/03/75

FROM: AUTHOR UNAVAILABLE; W. T. Coleman, Jr.; NHTSA

TO: Hon. Bob Packwood - U.S. Senate

TITLE: FMVSS INTERPRETATION

TEXT: Thank you for your letter of August 8, 1975, forwarding a copy of a letter to me from Mr. William G. White, President of Consolidated Freightways Corporation, and asking for early consideration of Mr. White's request. In that letter, Mr. White asks that the National Highway Traffic Safety Administration require reports from all truck operators and antilock system manufacturers on any malfunction they experience with antilock systems.

I have given full consideration to the important matter of collecting sufficient data on the reliability of antilock systems used on production vehicles, and I have responded to Mr. White with my conclusions. A copy of that response is enclosed to provide you with a complete explanation of my decision.

SINCERELY,

United States Senate COMMITTEE ON BANKING, HOUSING AND URBAN AFFAIRS

August 8, 1975

Honorable William T. Coleman, Jr. The Secretary of Transportation

I am attaching a copy of a letter from William White, Chairman of the Board of Consolidated Freightways, Inc. I am most interested in seeing that Mr. White's request is honored and would appreciate your early consideration of this matter. Could you please advise me of your ultimate decision.

As you may know, I have been following this matter regarding FMVSS 121 for some time. I have expressed my concern to the Administration over the hardships caused by this regulation and am awaiting their response at this time.

BOB PACKWOOD

cc: WILLIAM WHITE

CONSOLIDATED FREIGHTWAYS, INC.

July 31, 1975

Honorable William T. Coleman, Jr. The Secretary of Transportation

I attach copy of Dr. Gregory's letter to me of July 28th and my response to him.

I believe truck manufacturers, antiwheel lock device manufacturers and truck operators should be required by NHTSA to report any and all malfunctions of the antiwheel lock safety devices regardless of whether or not in their opinion the defect is safety related. All such reports should then find their way into the reliability file which has been set up in Room 5307, Motor Vehicle Programs, National Highway Traffic Safety Administration. NHTSA should not be allowed to screen such reports to determine whether or not they are "suitable for public scrutiny in light of applicable regulations and proprietary considerations".

Truck operators are now required to buy trucks with this equipment and are entitled to know exactly what problems are occurring in the field.

I will very much appreciate your looking into this matter.

WILLIAM G. WHITE -- CHAIRMAN OF THE BOARD

ID: nht75-3.36

DATE: 08/13/75

FROM: AUTHOR UNAVAILABLE; F. Berndt; NHTSA

TO: Construction Machinery Company

TITLE: FMVSS INTERPRETATION

TEXT: This responds to your June 18, 1975, question whether a system which pressurizes a water tank on a concrete mixer by means of air from the truck's air brake system would violate the requirements of Standard No. 121, Air brake systems.

The answer to your question is no. Standard No. 121 does not contain a prohibition on the use of air pressure from the air brake system for powering auxiliary devices. The vehicle must of course conform to Standard No. 121 following installation of the device if the installation occurs prior to the first purchase in good faith for purposes other than resale.

Although not a requirement of the standard, the National Highway Traffic Safety Administration does consider it appropriate that a pressure protection valve be placed in the line to the auxiliary device so that a rupture of an auxiliary line does not cause depletion of air pressure in the brake system.

SINCERELY,

June 18, 1975

T. Herlichy, Chief Counsel National Highway Traffic Division

I've talked to Mr. Williams about the method we use to take air from the air system of a truck to pressurize the water tanks on truck mounted concrete mixers. He in turn suggested I write you for an opinion whether or not the system comes under the brake regulation 121 and, if it does, whether we comply with it.

Basically the design is shown on Page 31, which is enclosed. Valves 4 & 5 on Page 31, are the same as the valves shown on Page 22. An air line runs from Valve 4 up to a control valve that allows the operator to add air to the water tank.

To give you a better idea of how the entire operation goes, let me describe the sequence of events when loading, mixing, and hauling concrete. First of all, the truck is driven under the batching plant at the ready mix yard and loaded with concrete. At the same time the driver fills the water tank with water. After the truck is loaded, it is driven out from under the plant to a mixing area where air is added to the water tank and the operator washes off whatever concrete that has accumulated on the mixer during charging. After the mixer is cleaned and the concrete is mixed, the truck is ready to go on the highway.

At this point no further air is taken from the truck system because either the water tank is completely pressurized or the operator will shut the air off to the water tank. So, while the truck is traveling from the ready mix plant to the job site, no air is taken from the truck brake system.

While on the job site the operator will add water to the mix and washdown the truck after the mixer is empty. He will again be taking air from the truck system. But before he returns to the highway either the water tank will be completely pressurized or the air shut off so that while he is traveling on the road no air will be used from the truck system.

I believe I have given you all the information needed, but if not, let me know what else is required and I will forward it to you.

CONSTRUCTION MACHINERY COMPANY

James E. Johnson, Chief Engineer Vice President-Director of Engineering

PRESSURE WATER SYSTEM

(Graphics omitted)

The air valves in the pressure water system are adjusted and set at the factory. Further adjustment should not be required except for possible adjustment of the height of dial as shown in illustration of leveling of water tank. The pressure regulator (1) is set to maintain a maximum pressure of 40 p.s.i. In the interest of safety this setting should not be exceeded. The relief valve (2) is set to crack open at 75 p.s.i. affording added protection for the system. Control valve (3) in the position shown, is admitting air to the tank, its normal operation position. Turning the valve handle 90 degrees clockwise shuts off the air supply and exhausts the air from the tank. When the air stops escaping, the water tank can be filled. Then moving the valve back to its original position will charge the tank with air. Valve (4) is a pressure hold-back valve. This valve prevents air from passing from the supply tank of the truck when the supply tank pressure is below 65 p.s.i. thus keeping pressure available for operating the truck brakes. Valve (5) is main shut off for all air to mixer water tank and controls.

To operate the pressure water system, open Valve "A". To add water to the drum, open Valve "C". To drain the entire system in freezing weather, open all valves "A", "B", "C", "D" and "F".

AIR SUPPLY TANK HOOK UP

HOOK INTO THE TRUCK AIR SUPPLY, USING THE METHOD SHOWN WHENEVER AIR IS TAKEN FROM THE TRUCK AIR SYSTEM FOR ANY MIXER CONTROL.

(Graphics omitted)

WATER TANK INSTALLATION (Illegible Data)