Inherited Atomic 4

[John Fosdick]

Hi my name is John Fosdick, and I am new to this forum. I inherited my Atomic 4 from my wife's uncle. He last had it in an old wooden whale boat that had been converted into a yawl. I had the pleasure of sailing on it once.

My wife's uncle got on in years and he could no longer keep up with the boat's maintenance. He got rid of the boat, but saved the engine. Unfortunately he passed away and I eventually got the engine.

My plan is to build an 18ft Goliath Tugboat and use the A4 for power. The Goliath is a Ken Hankinson design and the plans are sold by Glen L. My A4 has the transmission attached with a 3:1 reduction gear. It's raw water cooled and ran in salt water. It has an alternator. It ran fine when it was removed from the boat, and has been stored inside since (~15 years).

My wife gave me the boat plans for Christmas and that got me motivated to start working on the motor and see what I have. So far I have started removing components; added Marvel Mystery Oil to the cylinders; and done some cleaning. I did not get a hand crank with the motor so I fabricated one from some old 3/4"pipe (I'm a retired shop teacher). The good news was that she turned over with only a little initial effort.

I have a few questions and would appreciate any feedback. The engine does not have the brass plate on top of the transmission. Where else can I find a serial number/model number? What is the best way to check the block and manifold for cracks? Is this a suitable size engine for the boat that I want to build?

That's enough for now. Thanks in advance for any information,

John

PS How do I add photos to a thread?

[sastanley]

Hi John, Welcome to the group.

We have a couple other members that have put A4's into something besides a sailboat, so they may have some info for you regarding your design & the A-4's suitability, etc..

The serial number varies based on the engine (early or late model), & your pics will help us determine that! - Regardless, the casting date I think is stamped into every block, a 6 digit number under the carb on the port forward side of the block.

I can help with the picture attachment..this is a screenshot from when I was helping explain it to another forum member. Newer cameras produce HUGE images so be sure to downsize them to something reasonable so they are viewable..

[lat 64]

Hi,
I looked for a picture of your boat and found one here:

http://www.boats.com/boat-details/Mini-PH-Tugboat-%22Goliath%22/117446471

I think that's a perfect match for the a-4!
I see you wrote 3 :1 reduction, I was only aware of a 2;1 reduction for the a-4. either way, I think you will have some concerns about getting a prop big enough to take advantage of the reduction. By that I mean on a small boat the prop shaft will be closer to the bottom of the hull reducing the prop aperture and forcing a smaller diameter. You don't have any of the compromise issues that sailboats have, so you can use a 3 or 4 blade prop with lots of area. If you are required to fit a smaller prop, a direct drive a-4 will make it possible to turn it faster, thus getting to use more of the available power. If this is a real issue(and not my imagination running wild), then you can convert the 2:1 to a direct drive with some bits and parts from Moyers (I think).
I have the 2:1 reduction on my boat and it is fitted with a 2-blade, 16-inch prop that works about right for a 12,000 lb boat. It is a sailboat prop though, and so many variables to consider, that it's not proper to even compare. I highly recommend Dave Gerr's The Propellor Handbook from International Marine publishing.

I'm sure the designer has specs for this stuff.

welcome,
Russ

[Marian Claire]

Another welcome. I will take a stab at the last question. From what I read it uses a Yanmar 3gm30. So the HP is close to the A-4. I am not familiar with the diesel rpm to HP ratios but with the A-4 you will need to hit 2500 rpm to get 20 HP and with the 2 to 1 reduction that should be doable with the proper prop. With only 3500 lbs displacement you should need less than 10 hp to move her along. Based on 1 hp /500 lbs. So I think the A-4 would be easily up to the task. Dan S/V Marian Claire

http://www.grayandgrayyachts.com/core/listing/pl_boat_full_detail.jsp?slim=broker&boat_id=2295889&ybw=&hosturl=grayandgray&&units=Feet&access=Public&listing_id=1572&url=&hosturl=grayandgray&

Edit: I do type to slow....

[ArtJ]

It is possible that the engine, depending on age, may be an earlier engine
from universal than the atomic 4 and was produced earlier, but is similar.
If this is something possible, then perhaps a forum member could point
to the history of the atomic 4 which illustrates earlier related engines.
The reason I mention this is because of the storage and the possible 3:1
reduction.

Also, look at the engine pictures posted on the rebuild section of this website
look for any differences to your engine

Best Regards,

Art

[H3LlIoN]

Just saw the pics in the link that lat64 posted...that's a sweet little tug!

Best of luck with the project, and welcome!

[CalebD]

There was a young fellow here who launched a 20' motor boat he called "Geoduck" using an A4 as the engine. Can't find the thread but here is a video:

http://www.youtube.com/watch?v=PwHW9moWJn8

[John Fosdick]

Thank You All!

Thank you all for the warm welcome to the forum and all of the helpful information. I have some pictures of my cast iron baby that I will attempt to upload to this thread!

First of all I need to admit that I was in error when I stated the reduction gear as a 3:1. I do believe that it is a 2:1. I have some additional information thanks to your feedback! The lower left side of the block is cast the letters U J and UF When I removed some paint near there I found a faint stamping that looks like 3/12/67 (date of manufacture?). Where the transmission attaches to the block on top is cast UJ - 5 UF. Stamped just below that in a rectangle is 5 24 67 B (also a date?). On top of the reduction gear housing is an oval brass plaque denoting the unit as a Paragon Reduction Gear Model# R020 Serial# 5J1344.

When I got the motor it came with two prop shafts, a strut, rudder w/post and quadrant, and four different props. I hope that one or more maybe suitable. I plan on getting the prop book mentioned. I also plan on getting the Moyer Marine Manual.

Thanks again for the warm welcome and all of your help. I am very happy that I joined this forum.

Take Care,

John

[sastanley]

now we are getting somewhere. The head at least is a late model with the t-stat dome & 1/2" hose over to the (non-Universal brand) manifold. However, I am going to guess it is a late model head on an early model block since you do not have an oil fill over the flywheel.

That bell shaped thing is a 2:1 reduction gear attached to the back.

Up on the front of the motor where the rusty nut is, that is the location for a water temp sensor..and it looks like you have mechanical oil pressure gauge coming right out of the spot where most have a sensor for the OP gauge. Looks good!

Down where the "UJ" is on the first pic, hopefully is a casting date...behind and to the right of the oil pressure gauge. Mine is something like 041276 - "April 12, 1976"

The other thing (minor detail) is that you should not have a glass bowl/filter on the mechanical fuel pump. On gas inboards they are supposed to be metal...so that might be an aftermarket change too...a lot of us have an external Racor style fuel filter/water separator. however, if I could find a filter to fit into the fuel pump bowl, I would put one in there too!!

we'll deal with all these as we go along..no reason to be alarmed.

[hanleyclifford]

Interesting engine. Late head, early starter, carb, possible late manifold, Sherwood? water pump...should be fun.

[John Fosdick]

Inherited A4 Continued

Hi All,
I did find the date numbers on the block which means that it must have been cast in '67. Now I'll need to start scraping paint off of the head to look for a casting date there. I've owned many older wooden boats (it's a sickness) with flathead inboards (mostly GrayMarine's). Back in the 50's and earlier the glass bowl on the fuel pump was standard. I will add will that to my list of things to upgrade. I have not gotten to rebuilding the carb and fuel pump yet. I'll be looking into switching to an electic fuel pump.

I'm attaching a few more pictures of her (apologize for the giant size). I still haven't found the right program to downsize my pics.

Take Care,

John

[jpian0923]

You don't need a program to resize pictures. All you have to do is change the setting on the camera.

Something in the 150k range is perfect for this forum, or any other forum.

By the way, looking forward to your rebuild.

[Marian Claire]

A thing of beauty. Early style distributor to add to the mix. Just found this: Reduction gear ratio options 2.04:1, 3.01:1 From: http://www.cncphotoalbum.com/atomic4/atomic4specs.htm
I never knew that there was a 3 to 1 option. Dan S/V Marian Claire

[sastanley]

That reduction gear is like gold around here...I think it will be great for your boat.

If you are switching to an electric fuel pump (Facets are popular) you won't need to worry about the glass bowl...that whole assembly is part of the mechanical fuel pump. Later mech pumps had a fine mesh screen inside of the metal bowl and the larger particles it stopped were supposed to sink to the bottom of the (metal) fuel bowl I think. Some people have found small cartridge filters (like the one we can see thru the glass bowl) that fit in there OK, which would probably replace the mesh screen. In these days of ethanol fuel, many of us now run a 10 micron water separating Racor filter mounted between the tank & pump, and then a smaller in-line filter (7 micron I think) between the pump & carb as final defense against dirt.

Paint.NET is a free graphics program that will resize your pics..they aren't too terribly huge though. Like Jim said, you might be able to 'dumb' them down at the camera. I personally like to take them big on the camera for detail & then keep the originals on my home server & post up less bandwidth intensive pics on the site. If you still have a computer with Windows XP, there is a powertoy available from Microsoft called "picture resizer" that lets you do it from your mouse with a simple right-click.

[H3LlIoN]

picresize.com is what I normally use, or tinypic if I want it hosted online.