Helpful Hints

4 HP Doak

Courtesy of John Toom, 2004 Avenida Penasco, El Cajon, California 92021.

John Toom

Content Tools

1427 Wessyngton Road, N.E. Atlanta, Georgia 30306

I'd like to tell the readers that a new and better way of striping a new paint job has been found. Last April I made a test panel and put it out in the sun and weather for more than three months and the stripe did not fail. The secret is to use a felt tip permanent ink marker. They can be bought from office supply houses or book stores. The marker must be labeled 'Waterproof', permanent ink.

Water color markers will not hold up, even for one day in the sun. Care must be taken when striping not to overshoot a stopping point, because it is impossible to cover up your error by using more paint. This ink will bleed through any color paint in a day or two. Happy striping!

Another hint is where to buy gasoline check valves that are used in our gasoline tanks. I found two sources, one is Briggs & Stratton 'Pipe Fuel' #293700 or NAPA #7-023040. Both are made of brass with a strainer and can be bought for less than $2.00 each. The two inch long stem can be pushed into a 1/4' O.D. copper tube and soldered. Or, this new 1/4' O.D. plastic tubing will fit tightly on the check valve steam. Drop in your tank and your check valve troubles are gone forever. Note: They must be used vertically - will not work in a horizontal position.

If the brethren will use American Super Lead-Free gasoline, there will be no sticky varnish residue left in the tank or fuel lines and none to stick the check valve either, open or closed. A stuck check valve, either open or closed will cause irregular running and very hard starting.

A Gulf Oil Corp. engineer told me that the gasoline used up to 1924 had an Octane rating of 64. This is the Octane number our old engines were designed to use. The nearest fuel that we can buy today (64 Octane) is VM&P Naptha. It will run, but makes the engine hard to start when either hot or cold, so would not recommend its use. Also, it causes an abnormal amount of black smoke and soft carbon which we don't need. So, let's stick to American Super Lead Free gasoline to save us unneeded trouble.

There will be no difficulty in buying new piston rings if we buy from a well-stocked automotive parts supply house. They should be bought by diameter size and width of the ring. Unless the engine is honed only, standard size rings should still be used. Since our old engines normally used wide rings eg: 1/4', 5/16', 3/8' etc. a ring one half or even one third the required width can be used by installing more than one ring per groove. By using two or more rings per groove, the compression pressure will be increased and the ring will seat itself with less 'running in' time than when using a wide ring, per the original width. The ring width does not have to be equal for a groove. Example: A 3/8' groove can take three 1/8' rings or one 1/4' and 1/8' ring.

This engine is a 4 HP Doak, Shop Number 503, made in Oakland, California. The igniter and igniter trip linkage is missing. I would like to hear from anyone who has information or a similar engine so that the missing parts could be reproduced.

NOTE: A ring groove must be absolutely free from hard carbon. A ring groove carbon remover tool can be bought or a broken original ring can be ground or filed to a sharp edge on one end and used to cut the carbon out. If this carbon is not completely removed, down to bare metal, the new rings will be crushed or broken when the piston is pushed into the cylinder bore. Pour plenty of engine oil on the new rings and piston just before pushing in place. Be sure to space the ring gaps 180 deg. apart when using two per groove and 120 deg. apart when using three per groove.

If a flywheel is a little loose on the shaft, the 'Gib Head' key can be pulled out and placed in a vise and bent about 10 deg. or 15 deg. in either direction or both directions or if the key slot is worn too wide also. If there is a great difference in the shaft and wheel diameters, the above operation will not cure the trouble.

There is no reason to pay 8, 10 or 12 dollars for an induction coil as used with a 'make and break' ignition system. Buy a 100 foot roll of #18 gauge insulated or varnished hook-up copper wire (Solid) which is wound on a metal spool. Usually, both ends of the wire on the spool are accessible. If so, a few rounds of tape can be wound on the roll of wire to keep it from unwinding. There is usually an opening in the center of the metal spool. If so, all that is needed to make a complete working induction coil is to fill the center of the spool with short pieces of soft iron wire. Your fence or your neighbor's fence will supply the iron wire. Cut enough pieces the length of the spool to fill the center space, then drive in a few more pieces to make tight. Hook one wire of the coil to the igniter and the other to the battery and have a good working coil for about $2.00 or less. This coil will work with a 6, 8, 10, 12 or 16 volt battery. The higher the battery voltage, the bigger the spark. Do not hook to house wiring. Belden #8528-100, 18AWG Solid Hook-up wire will do the job. This can be secured from a radio or electrical supply house.

For the benefit of those who may have a 3 HP Jumbo engine with a 'no-good' zinc Remy Bros. high tension magneto, we recommend the following: A type RM Edison Splitdorf Corp. magneto as is used on a Gravely Tractor engine, can be adapted as a replacement.

A small 1 HP International make and break engine, compactly mounted on cart. It has Wizard low tension flywheel magneto.

Before and after photos of my recently restored 4 HP Olds engine. This is a very early one made by R.E. Olds - still retaining some of the casting features as used in the steam engines he manufactured before gas engines in the 1890s.

Remove the impulse starting unit, take out the armature and turn, on a lathe, the shaft down to 7/16' diameter to fit the latch-off arm of the Remy. Then mill off 3/8' of an inch of the magneto housing base to equal the height of the Remy from the base to the center of the armature shaft. Tap out the present base mounting bolt holes as deep as you can with a 'bottom tap'. The key-way in the latch-off arm and the key-way in the armature shaft will match up for proper timing, as is. However, the Woodruff key will have to be filed off some to enter the latch-off arm. Turn the plastic magneto top cap 180 deg. and screw on. This is necessary to keep the latch-off arm 'pull finger' from hitting the cap terminal. This adaptation will work like a charm and you will be free of further magneto troubles with your Jumbo. I do not know whether this change will work on other sizes of the Jumbo, but it may do so. Try it!