Universal Atomic 4 & Stevedore

PATH: Boat Production » Boat Equipment » Propulsion » Engines » Universal »

Universal Motor Company: Introduction, History, Contact Information Links, etc.
Universal Atomic Four: Overview, History, Early-Late Differences, Features, etc.
Universal Atomic Four: Specifications, Years Manufactured, and Duty Ratings.
Documentation: Catalogs, Brochures, SpecSheets, Manuals, Parts Lists. Recalls, etc.
Forum Posts, Tech Notes & Tech Tips.
Publications & Media: Articles, Books, Magazines, Videos, Websites, Authors, etc.
Related EAB Webpages & Main Topic Pages with Links.
Visit our FEATURED ARTICLES Home Page! Thanks to our amazing contributors.
This Months Top 20 Most Popular Articles on our EAB Website.
Members must SIGN IN to gain access to Members Only areas of this website.
Become an Academy Member and gain access to additional pages and programs!
Comments for everyone to view: Submit to Comments-EAB@AnchorsAweighAcademy.org.
Comments for everyone to view: Submit to Comments@EverythingAboutBoats.org.

See our Universal Motor Company webpage for company overview, history and contact information, PLUS information about their other products.

Atomic 4
and Stevedore
(The Stevedore is a de-tuned lower 18.5 horsepower version of the 30 HP Atomic 4)

The Universal Atomic 4 is a four-cylinder, 64.46 cubic inch, 30 horsepower (22 kW) gasoline engine produced by the Universal Motor Company between 1947 and 1984 for use as auxiliary power on sailboats. Over 40,000 of the engines were produced during that time, with an estimated 20,000 still in use today. This “workhorse” engine dominated the expanding sailboat market starting in the 1960’s, and between the years of 1965 and 1975 they were installed on up to 80% of new sailboats in the 25-40 foot (7.6-12 meter) range. Their longevity and reliability is proven by the fact that thousands of sailors still depend on the engine. The Stevedore is a slower revving lower horsepower version of the Atomic 4 engine.

Atomic 4

Universal Atomic 4 & Stevedore
History and Lineage

The Atomic 4 is descended from an earlier Universal Motor Company design called the Utility Four, which was used extensively in World War II by the United States Navy and allies to power the lifeboats for the ships, barges, and tankers of many navies and merchant marine fleets. The Utility Four model was replaced by the Atomic 4 in 1947.

The Difference Between Early and Late Models

Most parts are interchangeable between early and late model engines. However, a few parts (particularly some of those used in fuel, ignition, and cooling systems) are unique to early or late models.

If you have an original engine from the mid-seventies or later, with an oil fill tube over the flywheel housing in front of the engine, you can be reasonably sure that your engine will require all late model parts.

If your engine does not have an oil fill tube over the flywheel housing, it may require a mix of late and early model parts. You will therefore need the following information before ordering:

1. To order ignition parts (including the “Ignitor”), you will need to know if your distributor was manufactured by Delco (used on late model engines), or by Prestolite (used on early model engines). Prestolite distributors are distinctively smaller in size, and their condensers are mounted on the outside of the distributor housing.

2. To order cooling system parts, you will need to know if your engine has a thermostat housing (a small dome-shaped casting) located on the front corner of the head, nearest the starter. This thermostat housing would indicate that your engine has a late model cooling system.

3. To order carburetor parts, you will need to know if your carburetor is made of aluminum or cast iron. Aluminum carburetors were used on late model engines. All carburetors were manufactured by Zenith or Bendix, so the manufacturer does not help in determining your carburetor vintage.

4. To order gaskets, you will need to know (1) and (2) above, plus the shape of your transmission cover. Late model engines used a square cover, and early model engines used a rectangular cover with a curved top (“tombstone-shaped”).

5. Late model (Delco) starter ring gears have slightly smaller teeth than early model Prestolite ring gears.  For this reason, Prestolite and Delco starters cannot be exchanged between early and late model engines unless the ring gear (or entire flywheel) is changed with them. In addition, late model ring gears have a slightly larger diameter than early models, so when moving a late model flywheel to an early model engine, either a late model housing will also have to be moved along with the flywheel or the six (6) small boss areas the inside of an early model flywheel housing will have to be ground down.  These boss areas are for the ¼ – 20 bolts that hold the flywheel cover on, and they will have to be ground down almost to the bolt holes themselves.

From MoyerMarine.com.

Engine Features

Top End: The Atomic 4 engine is a type of side-valve design, commonly called a “L-head” or “Flat Head” engine with all the intake and exhaust valves located in the cylinder block beside the cylinders rather then in the cylinder head. The valve train is very simple and consists of the intake and exhaust valves, return springs and tappets. Unlike the more complex valve-in-head type engines, no rocker arms, push rods or large and heavy “ported” cylinder heads are required. Unfortunately, a significant drawback to this simple design is the limited compression ratio that is attainable due to the large amount of space required for the side valves to open into the combustion chamber. The side-valve design was popularized in Ford “Model T’s”, “Model A’s, and “Flat-Head V8’s”. Surprisingly, the side-valve design is making a comeback in light aircraft engines. Read more about the Belgian D-Motor flat-fours and flat-sixes at Wikipedia.

From Wikipedia.

Like most side-valve type engines which suffer from low compression as described above, the Atomic 4 would undoubtedly benefit performance-wise with “Intake Air Charging”. Supercharging is however NOT recommended, because of the Atomic 4’s “Weak-Bottom-End” described next.

Bottom End: Unlike most 4-cylinder inline engines, the Atomic 4 crankshaft has only two main bearings, one in the front and one in the rear (see crankshaft above). Instead of a main bearing in the middle (between #2 & #3 connecting rod journals) the crankshaft has a counterweight that helps the crankshaft maintain its stability. Because of this engine’s low compression ratio, low power output, and relatively low operating RPM, it does not develop very high loading of the crankshaft bearings and therefore normally never needed the 3rd, 4th, or 5th crankshaft main bearings like other 4-cylinder inline marine engines. However, the lack of support for the middle of the crankshaft does make the Atomic 4 a poor candidate to “soup-up” for competition racing. The Atomic 4 crankshaft can flex and even break, especially during high engine output and/or when under high rotational, gyroscopic and/or inertial loads from the pistons, rods, crankshaft and flywheel. Such loads on the crankshaft can become very high, such as when a small vessel attains high speed in choppy water.

Lubrication: The Atomic 4 engine was equipped with pressurized lubrication to all crankshaft bearings (note the oil feed holes drilled into the crankshaft above). Unfortunately, it lacked an oil filter which would seem to be a worthwhile addition considering that the integral transmission runs in the engine lubricating oil and generates additional wear metals in the oil. A bypass type oil filter can easily be fitted to this engine. Some new engine blocks from “aftermarket” sources like Moyer Marine are machined to be fitted with full-flow type oil filters.

Cooling: Most Atomic 4 engines originally lacked fresh water cooling. The standard raw water cooling system caused cylinder block, cylinder head and exhaust manifold casting breaches especially in salt water from simple “rust-thru” which has resulted in far too many Atomic 4’s being thrown away due to the resulting internal damage. Engines run in salt water would undoubtedly benefit from being fitted with a fresh water cooling system. Freeze damage resulting from a lack of proper winterization has also taken it’s toll of these engines. Fortunately, new engine blocks, cylinder heads and exhaust manifolds have become available from “aftermarket” sources like Moyer Marine.

Atomic 4 Head – Shows salt water flooding of engine.

Exhaust: The Atomic 4 was fitted with a 1 1/4” pipe thread plate at the end of the exhaust manifold for the engine installer to design and fit a proper exhaust system for the particular vessel. The exhaust system could be a “dry” system or a “wet” system depending on the preference. Unfortunately, many exhaust systems were not designed and/or installed according to good practice, and consequently failed, often with disastrous results. Make sure that your engine’s exhaust is properly designed and installed before it fails.

Atomic 4 Exhaust with poorly designed mixing elbow.

The engine’s exhaust system is one of the vessel’s systems that requires vigilant attention, however it is often the most neglected. Exhaust system components deteriorate rapidly. Make sure that your engine’s exhaust system is in good condition before it fails.

Toxic fumes, flooding bilges, flooded engines, and vessel fires are just a few of the consequences of failed exhaust systems. Make sure that your exhaust system is not going to kill you, please.

Loyal Following

Considering that very few of these engines have suffered failure from any inherent weakness, such as a manufacturer’s design deficiency, manufacturing fault, or defect in materials, its no wonder that this tough little motor has outlasted many of it’s critics and has gained a fiercely loyal following which can be ultimately attributed to it’s rugged simplicity and strength in numbers.

Specifications For Universal Atomic 4 and Stevedore
4-Stroke Cycle Gasoline (Petrol) Marine Engines

⊗ = Data Not Available from Data Source. ? = …? = ¿…? = Data Not Confirmed.
DS = Data Source: …+ = ++ = Data combined from Multiple Sources. BD = BoatDiesel.com = …B.
^  …f = Forum. …w = Webpage. …c = Catalog. …b = Brochure. …s = SpecSheet.
^  …o = Owner’s/Operator’s Manual. …m = Service/Repair/Technical/Workshop/Shop Manual.
^  …1,2,3,A,B,C,etc = Source #, Version, Revision.
CYL = Cylinder Configuration-Number−Liner Type:
^  Cylinder Configuration: u… = Vertical (Upright). I = In-Line.
^  Liner Type: P = Parent/Native Bore. b… = Borable Oversize. …s = Sleevable.
^  ^  Liner type sometimes had to be determined from Shop Manual and/or Parts List.
BORE & STROKE: …mm = Millimeters. …” = …in = Inches.
DISPLACEMENT: …cc = Cubic Centimeters (cm³). …L = Liters (Litres). …ci = Cubic Inches (in³).
⇑ = Base Engine Manufacturer. ⇒ = Engine Marinizer (Mariniser).
MODEL: EC = Engine Code. Cylinder Block Capacity ID Code. TC = Turbocharged.
RATING: See the Engine Duty Ratings at the end of the table.
ASP: Aspiration-Fueling: N = Naturally Aspirated. C = Carbureted.
POWER: kW = Kilowatts. HP = Horsepower. MHP = Metric Horsepower.
@RPM = Power Ratings @ Revolutions Per Minute.
YEARS MFR’d: Beginning-Ending. Trailing “–” (Dash) without an Ending Date = Still in Production.

Click on Data Source Links for Catalogs, Brochures, SpecSheets, Operator’s Manuals, Shop Manuals, etc.

Universal Atomic 4 Ub uI-4−P ⊗mm ⊗mm 2-9/15*in 3-1/8in ⊗cc / ⊗L / 65ci
Universal Atomic 4 Uh uI-4−P ⊗mm ⊗mm ⊗in ⊗in ⊗cc / ⊗L / 64.46ci
Universal Atomic 4 Wi ⊗-⊗−⊗ ⊗mm ⊗mm 2-9/16in 3-1/8in ⊗cc / ⊗L / 64.46ci
Universal Stevedore Ub uI-4−P ⊗mm ⊗mm 2-9/15*in 3-1/8in ⊗cc / ⊗L / 65ci
Atomic Four − ⊗ Ub N-C 7.3 1000 1947-1984
Atomic Four − ⊗ Ub N-C 11.9 1500 1947-1984
Atomic Four − ⊗ Ub N-C 16.2 2000 1947-1984
Atomic Four − ⊗ Ub N-C 20 2500 1947-1984
Atomic Four − ⊗ Ub N-C 25 3000 1947-1984
Atomic Four − ⊗ Ub N-C 30 3500 1947-1984
Atomic Four − ⊗ Uh N-C 22 30 1947-1984
Atomic Four − ⊗ Wi N-C 5 600 1947-1984
Atomic Four − ⊗ Wi N-C 7.3 1000 1947-1984
Atomic Four − ⊗ Wi N-C 11.9 1500 1947-1984
Atomic Four − ⊗ Wi N-C 16.2 2000 1947-1984
Atomic Four − ⊗ Wi N-C 20 2500 1947-1984
Atomic Four − ⊗ Wi N-C 25 3000 1947-1984
Atomic Four − ⊗ Wi N-C 30 3500 1947-1984
Stevedore** − ⊗ Ub N-C 7.0 1000 1947-1984
Stevedore** − ⊗ Ub N-C 11.0 1500 1947-1984
Stevedore** − ⊗ Ub N-C 14.5 2000 1947-1984
Stevedore** − ⊗ Ub N-C 17 2500 1947-1984
Stevedore** − ⊗ Ub N-C 13.8 18.5 3000 1975?-1984?
Stevedore** − ⊗ Uh N-C 13.8 18.5 3000 1975?-1984?
NOTES: *2-9/15in is a error in the brochure. It should read 2-9/16in. **Stevedore was Canadian limited horsepower version of Atomic 4. Stevedore: Model UJ – 5101 (direct drive) / UJR – 5102 (2:1 reduction gear) / UJVD – 5103 (V drive, 1:1, 1.29:1, 1.67:1, 2:1 reduction gear options).  Available as Automatic. Model UJS – 5111 (direct drive), Model UJSR – 5112 (reduction drive), Model UJVD – 5113 (V drive),
L-Head. Compression Ratio: 6.3:1.
Engine Rotation: Counter-clockwise from flywheel end.
Firing Order: 1-2-4-3 (no. 1 on flywheel end).
Reduction Gear Ratio: 2.04:1 or direct 1:1 drive.
Maximum Operating Angle: ~15 degrees.
Fuel: regular leaded gasoline (will function on unleaded fuel with precautions).
Lubrication Oil: SAE 30.

More from Wikipedia.

If you can help us add brand information, Spec Sheets, Manuals, etc. that we lack, please submit the link or PDF To⇒editor@everythingaboutboats.org so we can add it to the website. Thanks.

Universal Motor Company
Engine Duty Ratings

Con = Continuous = Commercial

Int = Intermittent = Pleasure Craft

Gen = GenSet = Generator (Constant Speed)

Engine Documentation

Universal Atomic 4 & Stevedore Auxiliary Sailboat Engines (800101) — Westerbeke
^ Includes Specifications‚ Installation Dimensions‚ and Price List.
Price List:
Included in Universal Atomic 4 & Stevedore Brochure above.
SpecSheets/Data Sheets:
Included in Universal Atomic 4 & Stevedore Brochure above.
Charts and Graphs:
Press Releases (by Date = YYMMDD):
Model History:
Westerbeke Propulsion Model History — Westerbeke
Serial Number Guide (Manufacture Date Code Identification):
Installation Instructions/Manuals:
Westerbeke Installation Manual – Marine Engines & Generators – Diesel and Gasoline — Westerbeke
Installation Diagrams & Drawings with Dimensions:
Included in Universal Atomic 4 & Stevedore Brochure above.
OpManuals (Owner's/Operator's Handbooks/Guides/Manuals):
Universal Atomic 4 Operation and Maintenance Manual P/N 200156 80 pages — Westerbeke
Universal Atomic 4 Owners & Service Manual — Moyer Marine.
Universal Atomic 4 Owner and Service ManualL-36.
universal Atomic 4 Owners ManualL-36.
universal Atomic 4 Transmission ManualL-36.
Parts Schematics with Exploded Views & Parts Lists:
Universal Atomic Four Parts List P/N 200150 — Westerbeke
Universal Atomic 4 Parts ListWesterbeke (From Moyer Marine).
Universal Atomic 4 Parts ManualL-36.
Parts Bulletins:
Universal Superseded Parts List (August 2017)Universal
Shop Manuals (Repair/Service/Technical/Workshop):
MMI Universal Atomic 4 Service and Overhaul Manual — Moyer Marine.
Atomic 4 Owner and Service ManualL-36.
Atomic 4 Transmission ManualL-36.
Wiring Diagrams:
Service Bulletins (by Date YYMMDD):
Westerbeke SB#242 (040824) – Mfr Date Code — Westerbeke.
Westerbeke SB#227 (031027) – 180 Degree Thermostat Kit PN# 200468 — Westerbeke.
Westerbeke SB#238 (030228) – Fuel Pump Inlet Filter Part Number 048076 — Westerbeke.
Westerbeke SB#223 (960515) – Cylinder Head Gasket PN# 263776 — Westerbeke.
Westerbeke SB#155 (850621) – Keyswitch — Westerbeke.
Westerbeke SB#136 (840209) – Shift Lever — Westerbeke.
Westerbeke SB#125 (830814) – Oil Pressure Switches — Westerbeke.
Product Recalls:

Forum Posts, Tech Notes, Tech Tips & FAQs

If you think we should add a Forum Post, Tech Note or Tech Tip to this section, please submit the Link via email to⇒Editor@EverythingAboutBoats.org


Related Media
with Links to EAB's Media Overview and Creator Profile Pages

Media with Bold Titles are part of our Academy Library!
Academy Members can view the Media by clicking on its Bold Title Link to go to its
EAB overview page and then scrolling down to the "Academy Library" section for its link.

To help us alphabetize the book list below, each leading grammatical
article ("The" - "A" - "An") has been moved to the end of the title.
DS = Data Source code

Atomic 4 Basics by Tom Averne — 48° North.
ANCHOR‚ The — Anchors Aweigh Academy.
DIY Boat Owner — The Marine Maintenance Magazine.
Moyer Marine's Online Atomic 4 Newsletters — Moyer Marine.
^ Spring 2010:
^ ^ Exhaust issues.
^ ^ Oil Change Issues.
^ ^ Spring Commissioning.
^ Summer 2010:
^ ^ Impeller issues.
^ ^ Oil pump basics.
^ ^ Engine Inspection Checklist.
^ ^ Synthetic Oil and Wet Clutch Slippage.
^ Winter 2010:
^ ^ "Are you operating in a vacuum"?
^ ^ Tartan 30 and 34 standpipe mufflers.
^ ^ 10 things you really don't want to do.
^ Spring 2011:
^ ^ Preventative Maintenance Program.
^ Fall 2011:
^ ^ Troubleshooting Concepts.
^ ^ Fall Manifold Special!
^ ^ Setting your belt tension just got easier.
^ ^ New split hub prop shaft couplings.
^ Spring 2012:
^ ^ Springtime startup issues.
^ ^ Suggested Spare Parts and Tools for Cruising.
^ Winter 2014:
^ ^ Sudden and unexpected shutdowns.
^ Winter 2017:
^ ^ Introduction to induction.
^ Winter 2018:
^ ^ Understanding the Atomic 4 oil system.
^ July 2018:
^ ^ Understanding the Atomic 4 late model cooling bypass system.
^ Special Announcement:
^ ^ New Atomic 4 Blocks!

If media should be added to this list, please submit via email

CLICK HERE to discover how you can become a Member and gain FULL access to
thousands of expanded pages and dozens of excellent programs including our library

CLICK HERE to view ALL the books, magazinesvideos, etc. in our Academy Library.
They are also listed by category on the Topic Pages found on the Right Sidebar
CLICK HERE to donate any books, magazines or videos to our Library.

Related EAB Webpages


Related Main Topic & Subtopic Pages w/Links
All Website Main Topic Pages are listed in the Right Sidebar

2.1 – Boat Designing Schools.
2.2 – Boat Designers (Naval Architects, Boat Plans, Kits, etc).
2.3 – Statutes & Standards.
2.3.1 – Laws by Country. – Laws: Canada. – Laws: United Kingdom. – Laws: United States.
2.3.2 – Industry Standards. – International Maritime Organization (IMO). – International Standards Organization (ISO). – American Boat and Yacht Council (ABYC). – National Fire Protection Association (NFPA).
2.3.3 – Classification Societies. – Lloyd’s Register. – American Bureau of Shipping.
2.4 – Boat Building Tools & Equipment (Vendors, Specs, Manuals, Recalls, etc).
2.5 – Boat Materials (Vendors, Specs, Manuals, Recalls, etc).
2.5.1 – Wood.
2.5.2 – Metal: Iron, Steel, Aluminum, etc.
2.5.3 – Ferrocement.
2.5.4 – Fiberglass.
2.6 – Boat Equipment (Vendors, Specs, Manuals, Reviews, Recalls, etc).
2.6.1 – Steering & Thrusters.
2.6.2 – Stabilizers & Trim Plates.
2.6.3 – Dewatering Devices.
2.6.4 – Galvanic Corrosion Protection.
2.6.5 – Hull Penetrations & Openings (Thru-Hulls, Scuttles, Skylights, Hatches, etc).
2.6.6 – Deck Hardware & Equipment. – Ground Tackle. – Commercial Fishing Gear.
2.6.7 – Rigging (Rig Types, Standing Rigging, Running Rigging, Vendors, Riggers, etc). – Sails (Sail Types, Aerodynamics, Vendors, Sailmakers, etc).
2.6.8 – Propulsion Machinery (Types, Configurations, Features, Control Systems, etc). – Engines: Types & Vendors. – Engine-to-Marine Gear Interfaces (SAE Specs, Damper Plates, Jackshafts, etc). – Marine Gears (Reversing, Reduction; Mechanical, Hydraulic). – Shafting (Propshafts, Couplings, Seals, Bearings, Struts, Keys, Nuts, etc). – Propellers.
2.6.9 – Electrical Systems: DC & AC (Direct Current, Alternating Current, etc). – Auxiliary Generators. – DC-to-AC Invertors
2.6.10 – Domestic Systems. – LPG Systems. – Cabin Heating & Cooling. – Galley Appliances (Refrigeration, Galley Stoves, LPG/CNG Systems). – Water & Waste Systems. – Trash Disposal. – Furnishings (Cabinetry, furniture, Coverings, Entertainment, Weather, etc).
2.6.11 – Navigation & Communication Systems.
2.6.12 – Safety Equipment (PFDs, Life Rafts, Fire Ext., Alarms, Medical Kits).
2.6.13 – Personal Equipment. – Diving (Commercial & Sport). – Fishing (Sport). – Sailing (Foul Weather Gear, Safety Harnesses, etc). – Racing (Sail, Offshore Power, Powerboat, Hydroplane, etc). – Watersports (Surfing, Skiing, Boarding, Tubing, etc).
2.6.14 – Boat Trailers.
2.7 – Marine Suppliers by Country.
2.7.1 – Marine Suppliers: Canada.
2.7.2 – Marine Suppliers: United Kingdom.
2.7.3 – Marine Suppliers: United States.
2.8 – Boat Building Schools.
2.9 – Boat Builders: A~Z (w/Links to Model Specs, Manuals, Reviews, Recalls, etc).
2.9.1 – Boat Builders by Vessel Types.
2.9.2 – Boat Builders by Country. – Boat Builders: Canada. – Boat Builders: United Kingdom. – Boat Builders: United States. – Boat Builders by US MIC.
2.10 – Do-It-Yourself Boat Building.

15 – BOAT REFITTING: (Fitting-Out, Repair, Repowering, etc).
15.1 – Refitters by Country (Shipyards, Boatyards, Riggers, Shops, etc).
15.1.1 – Refitters: Canada.
15.1.2 – Refitters: United Kingdom.
15.1.3 – Refitters: United States.
15.2 – Boat Repair Schools (Hull, Systems, On-Board Equipment, Propulsion Machinery, etc).
15.3 – Do-It-Yourself Refitting (Installation, Maintenance, Troubleshooting, Repair, etc).
15.3.1 – DIY: Fundamentals. – DIY: Tools: Usage, Safety, etc. – DIY: Deterioration (Rot, Corrosion, Fatigue, etc). – DIY: Troubleshooting, Failure Analysis, etc.
15.3.2 – DIY: Vessel Structure. – DIY: Hull & Deck. – DIY: Steering & Thrusters (Mechanical, Hydraulic, etc). – DIY: Stabilizers & Trim Plates. – DIY: Dewatering Devices. – DIY: Galvanic Corrosion Protection. – DIY: Hull Penetrations & Openings (Thru-Hulls, Scuttles, Skylights, Hatches, etc). – DIY: Deck Hardware & Equipment. – DIY: Ground Tackle (Anchors, Rode, Windlass, etc). – DIY: Commercial Fishing Gear. – DIY: Rigging. – DIY: Sails.
15.3.3 – DIY: Propulsion Machinery (Control Systems, etc). – DIY: Engines (Troubleshooting, Repair, Rebuilding vs Repowering, etc). – DIY: Engine Mechanical (Pistons, Rods, Crankshafts, Blocks, Heads, Valves, etc). – DIY: Engine Lubrication (Splash, Forced, Oil, Filtration, Additives, Oil Analysis, etc). – DIY: Engine Fuel (Petrol/Gasoline, Diesel, CNG, etc). – DIY: Engine Electrical (Starting, Charging, Instrumentation, etc). – DIY: Engine Cooling (Air, Raw Water, Fresh Water, etc). – DIY: Engine Exhaust (Dry, Wet, etc). – DIY: Engine Mounting (Hard, Soft, etc). – DIY: Engine-to-Marine Gear Interfaces (Adapters, Dampers, Jackshafts, etc). – DIY: Marine Gears (Inboards, Inboard-Outboards, Outboards, Sail Drives, Pods, etc). – DIY: Shafting (Shafts, Couplings, Joints, Thrust Bearings, Seals, Cutlass, Struts, etc). – DIY: Propellers.
15.3.4 – DIY: Electrical Systems. – DIY: Direct Current. – DIY: Alternating Current. – DIY: Auxiliary Generators. – DIY: DC to AC Inverters.
15.3.5 – DIY: Domestic Systems. – DIY: LPG systems. – DIY: Cabin Heating & Cooling. – DIY: Galley Appliances. – DIY: Water & Waste Systems. – DIY: Trash Disposal. – DIY: Furnishings (Cabinetry, furniture, Coverings, Entertainment, Weather, etc).
15.3.6 – DIY: Nav & Comm Systems (Charts, Compass, GPS, Radar, Lts, Flares, EPIRB, VHF, etc).
15.3.7 – DIY: Safety Equipment (PFDs, Firefighting, Alarms, etc).
15.3.8 – DIY: Personal Equipment (Diving, Fishing, Sailing, Racing, Watersports, etc).
15.3.9 – DIY: Tenders.
15.3.10 – DIY: Boat Trailers.

16 – MEDIA w/Creator Directory (Authors, Editors, Publishers, etc) + Lending Library.
16.1 – Articles (w/Reviews).
16.2 – Books (w/Reviews).
16.3 – Magazines (w/Reviews).
16.4 – Product Documentation (SpecSheets, Installation Drawings, Manuals, Parts Books, etc).
16.5 – Videos (Movies, etc. w/Reviews).
16.6 – Websites (w/Reviews & Links).

If there is anything on this webpage that needs fixing, please let us know via email

to see examples of our website's comprehensive contents!

Thanks to our amazing contributors for the steady flow of articles, and to our dedicated all-volunteer staff who sort, polish and format them, everyday we get a little bit closer to our goal of
Everything About Boats. If you would like to submit an article,
See Submitting Articles.


Ford Industrial Power Products Diesel Engines
How to Identify Ford Diesel Engines
Ford 2715E
Lehman Mfg. Co.
Detroit Diesel 8.2
Universal Atomic 4
Chrysler & Force Outboards
Eska Outboard Motors
Perkins Engines
ZF Friedrichshafen AG
Allison Transmission
American Marine Ltd (Grand Banks)
Boat Inspection
Types of Marine Surveys
Marine Surveyors by Country
Boat Builders By MIC
Beta Marine
American Boat and Yacht Counsel (ABYC)
USCG NVIC 07-95 Guidance on Inspection, Repair and Maintenance of Wooden Hulls

What our nonprofit Anchors Aweigh Academy and its
EverythingAboutBoats.org website have accomplished so far.

  • Published over 300 website main topic webpages, many with full articles on the topic. See our Website Contents in the Right Sidebar for the listing of the main topic pages.
  • Published over 9,000 marine vendor webpages, all with their contact information, most with a description of their products and services, many with product documentation, specifications and independent reviews. (Includes: Boat designers, boat building tools, material and equipment manufacturers and suppliers, boat builders and dealers, yacht brokers, marine surveyors, boat insurers, boat transporters, skippers and crews, boatyards and marinas, yacht clubs, boat rentals and yacht charters, boating, seamanship and maritime schools, marine law attorneys and expert witnesses, boat refitters and repairers, book authors and publishers, and video producers)
  • Acquired over 120,000 pages of product documentation including Catalogs, Brochures, SpecSheets, Pictures, Serial Number Guides, Installation Manuals, OpManuals, Parts Schematics, Parts Bulletins, Shop Manuals, Wiring Diagrams, Service Bulletins, and Recalls. And have made all viewable to academy members through the EAB website.
  • Acquired over 1,200 books and magazine back issues in our academy library and so far have made over 700 viewable to academy members through the EAB website.
  • Published over 500 DIY How-To articles about boat design, construction, inspection, operation, maintenance, troubleshooting and repair. We are working hard to do more.

We are currently formatting and polishing the Anchors Aweigh Academy online and hands-on courses. The Marine Surveying course has proven to be excellent for both the beginner and the seasoned surveyor, and especially helpful to the Do-It-Yourselfer.

Current Academy Members must SIGN IN to gain FULL access to this
website including expanded pages and valuable Academy programs
like our Academy Lending Library and our Ask-An-Expert Program!

If your membership has expired, CLICK HERE to Renew.

CLICK HERE to discover how you can become a Member and gain FULL access to
thousands of expanded pages and articles, and dozens of excellent programs

Thank you for your support. You make this website possible.

Comments for Public Viewing

Submit any comments for public viewing via email

Please remember to put this webpage's title in the subject line of your email.
All comments are moderated before they appear on this page. See Comment Rules.

FROM Donald: "This is an awesome website. I found the information that I needed right away from one of the over 20,000 free articles that you provide as a public service. I'm surprised that so much if this site is free. But I still signed up so I could access the thousands of expanded pages, interesting articles, and dozens of valuable programs! The member's library of books, magazines and videos that I can view online is really terrific! I understand that you and your staff are all unpaid volunteers. Please keep up the good work. And I commend you for your plans to add another 10,000 free informative articles over the next year. I'm thrilled to support you in this endeavor with my small membership donation. Thanks again for all your hard work."

FROM Huey: "I agree with my Uncle, I too have found the articles to be very enlightening. They say that it will take about 100,000 articles to cover the full scope that they have envisioned for the website. They have over 20,000 articles so far and that's doing pretty well, but it could take several years to get the rest. I also noticed that many of the Main Topic Pages and some of the article pages are still in the rough draft stage. I guess that they will fill in as they can get volunteers to work on them. But what I can't figure out is why anyone would spend the time writing informative in depth articles just to give away free to this website for publication? What's in it for them?"

FROM Dewey: "Well Huey, to me It looks like most of the articles on this website are written by very informed people, like boating instructors, boat designers, boat builders, riggers, electricians, fitters, marine repair technicians and marine surveyors. Writing such articles helps establish them as knowledgeable professionals. After all, this website was originally created by a school for marine technicians and marine surveyors. The website is growing in content every day. They even had to move to a bigger, more powerful server because the website's traffic has been growing exponentially."

FROM Louie: "I agree with everyone above. This site is quickly becoming the ultimate reference resource about every aspect of boats and ships for everyone from the beginning recreational boater to the seasoned professional mariner. I use the topic pages on the right sidebar to browse around the website. It's like a Junior Woodchucks' Guidebook for Boaters. Their Members' Library of over 300 popular and obscure books and over 200 magazine back issues that can be viewed online is fabulous. The Academy's magazine is especially informative. On top of that, there is the "Ask-An-Expert program for members where you can get an expert's answer to any of your boat questions. And a whole years membership is only $25. What a deal! I really love being part of this "Everything About Boats" community and help provide thousands of helpful articles free to the public. I think that I'll sit down right now and write an article about my experiences boating with my uncle."

FROM Scrooge: "You rave about this website like it was the best thing since sliced bread. Well, I think it stinks. Sure, it has a lot of good information for boaters, and they're adding more every day, but it will probably never be finished. Furthermore, I don't even own a boat. And I wouldn't have a boat even if someone gave me one. Boats are a waste of money and time and energy and money! They're just a hole in the water you pour money into. If you gave me a boat, I'd sell it quicker then you could say Baggywrinkle. Then I'd lock up the cash with all my other money so I could keep my eye on it and count it every day. Bah humbug."

FROM Daisy: "I'm just so glad that Donald got the boat so we and the boys could enjoy boating — together. And of course all of the girls, April, May, and June, love to be on the water too, especially when that is where the boys are. Oh poor Scrooge, boating is more fun then you could possibly imagine."

FROM Scrooge: "After seeing how much fun you all have on the water together, I regret that I didn't have that much fun when I was young. I've had a change of heart, and I'm giving each of you a Lifetime Academy Membership."

FROM Editor: "For those of you that have stayed with us this far, many thanks. You inspire us to keep working on this labor of love. We know that we have a lot more to do. Ultimately, we hope that we can help you enjoy the wonder filled world of boating as much as we do. We are all waiting to see what you have to say about this webpage article. Submit any comments via email To⇒Comments@EverthingAboutBoats.org. Be sure to include this page's title in the subject line. Also, your corrections, updates, additions and suggestions are welcomed. Please submit them via email To⇒Editor@EverthingAboutBoats.org. Let's work together on this."

FROM old-sailer: Atomic 4 Serial Numbers by Year
A little history…
I have managed to find myself a lovely old 30 ft C&C sailboat. (I love the old boats and not interested in the new ones at all) Of course it has the venerable Atomic4 in it and I copied down the serial and model and sent it to Don to see if he could tell me the age, when made etc. He replied telling me what he could about my little girl that she’s one of the last late model units made but he also told me he has never seen any log of the serial numbers relative to year of manufacture. Sooooo….. I went hunting.
Here’s what I have come up with so far assembled from a number of web sites that have bits and pieces of information on the engine. I found one web site that had all kinds of info. and it’s the basis for the list here and then I added other info from other sites I came across adding to it. I simply offer it here for the benefit of all interested in this great old engine.

Circa 1949: Serial #?
Zenith series 61-M2AE7 cast iron carburetor with adjustable main jet.
Dole thermostat.
Auto-lite ignition.
Fairbanks Morse magneto (optional).
Auto-lite 6 volt starter.
Auto-lite 6 volt generator.
Prestolite distributor (1Gw60032E1X).
Bronze gear water pump.
Old style heat exchanger kit (optional).
5 unit control panel with mechanical tachometer, mechanical oil pressure gauge, mechanical Water temperature gauge

Circa 1962: Serial #?
Jabsco rubber impellor water pump (available as a replacement).
Prestolite 12 volt starter.
Leece Neville 12 volt alternator (optional).

Circa 1963: Serial #68____
Prestolite 12 volt generator.
Auto-lite 15 amp 12 volt generator (optional).
Delco Remy 24 amp 12 volt generator (optional).
Prestolite 35 amp 12 volt alternator (optional).
Prestolite 40 amp 12 volt alternator (optional).

Circa 1964: Serial #71____
Ongaro – Teleflex electric control panel with electric tachometer (optional), electric oil pressure gauge, electric water temperature gauge.

Circa 1965: Serial #77____
“Old” Sherwood (7 end cover screws) rubber impellor water pump.

Circa 1967: Serial #79476
New style cylinder head with thermost housing.
Holley thermostat.
New style Sendure heat exchanger kit (optional).
Medallion 6 unit control panel with electric tachometer (optional), electric oil pressure gauge, Electric water temperature gauge.

Circa 1967: Serial #170509
Zenith series 68-7 alumininum alloy carburetor with fixed main jet.
Delco Remy distributor (#1112446 – 2G11/6C16/3HI8).
Delco Remy 070FLX 12 volt coil.
Delco Remy 1107679starter and new ring gear to fit.
Larger flywheel housing to fit new ring gear.
Motorola 35 amp 12 volt alternator.
Motorola 51 amp 12 volt alternator (optional).
Oberdorfer model 202M3 rubber impellor water pump (fitted to most engines).

Circa 1967: Serial #171514
External valve chamber oil line no longer fitted.

Circa 1968: Serial #174340
Oberdorfer model 202M3 water pump standard.

Circa 1969: Serial #174802
New style valves (stamped “Eaton” or “Etn”).

Circa 1969: Serial #175503
New transmission housing, oil fill moved to front.

Circa 1970: Serial #176500
Valve guide inner diameter revised to .3145 – .3150 in (new valve guide/valve stem clearance specification of .003 – .004 in to prevent valves sticking in guides).

Circa 1972: Serial #178801
Paragon marine gear updated with new outer plate combined with pressure plate, and new wider metric gear carrier ball bearing.

Circa 1975: Serial #192787
New style deep flywheel housing and flat sheet metal cover.

Circa 1977: Serial #198___
New style electric instrument panel (electric tachometer optional).

Circa 1979: Serial #202987
Mechanical fuel pump replaced with Facet electric fuel pump and low oil pressure shut-off switch.

Circa 1980: Serial #204___
Production stopped (sales continued to 1984).

FROM ILikeRust: Numbers on side of Atomic 4 cylinder block.

There are two numbers on that side of the block on mine. Both are visible in this pic:

The lower one, which is bolder and more visible, is an integral part of the casting of the block itself, and I’m pretty sure it’s the serial number. Comparing this to some of the other pics I also have of the block, I think it’s 295369. Clearly not a date code.

The other number, which is either stamped into the casting or cast in using a removable insert in the mold, is lighter and not as strongly visible. It’s also upside-down. That is the date code. From the picture, it appears to be 022880, for Feb. 28, 1980. That makes sense, because I know that the engine was sold and installed in my boat as a brand-new engine in 1983.

FROM sastanley: That 295369 # I believe is a mold/casting number.