Merc KE-4 gas tank question

[green-thumbs]

At the risk of sounding very old school. you do not need a tap. You need a machinist with a
lathe and a thread gage. The taps in the larger sizes are uncommon and the gas cap thread may be a nonstandard size. Making a thread restorer by cutting the correct thread on a piece round stock of the correct size is not Rocket Science difficult. Richard White ( plug ) makes OMC tools and may wish to expand his offerings into the Dark Side.
Those of the current generation may find it hard to believe. but. once upon a time in America people fixed things and even improve them as a result.
Louis.

[huntleybill]

OK…so what size tap do I need to chase the filler spout threads??

[huntleybill]

OK Louis, so does someone already make a tool to fix these threads?

[20mercman]

I would love to have a tap of this size also. The small Mercury tank threads are the same thread as was used by OMC on their TD-TN motors. If fact, you can use the OMC cap if you want to. Carl would turn over in his grave, but the OMC cap was a real cap, not the cheap piece of junk plastic cap that Mercury used. The larger thread caps for Mercury came out when they went to a large fuel filter assembly that threaded into the bottom of the tank. That is why Dave Bernard wanted to see a photo of the bottom of the tank. I don’t have the sizes off the top of my head, but I think the small tank is 1 1/16" x 18, and the larger one is 1 3/16" x 16. These taps can be purchased for the $50 range, but that is a lot of money just to save a tank.

Steve

[dave-bernard]

the large tank is correct I have one. got it on amazon. for basically Free. applied for a card and got $50.00 credit on it.

[huntleybill]

Thank you Steve. If you can confirm that size, I would appreciate it. As a restorer, I would spend $50 for the tap because I could use it on several tanks. Besides, "He who dies with the most tools WINS"! 🙂

[green-thumbs]

Page 28 item 107 Part # 5070 Tap, fuel tank filler hole 1 1/8" x 18 N.S price net $15.48
Page 28 item 108 Part # 5071 Tap, fuel tank filler hole 1 3/16" x 16 N.S. price net $18.26
NOTE page 28 illustration says 1 3/16" while price list says 1 1/16
Another reason to have a machinist at least verify the thread size
Prices are 1940s REAL dollars…minimum wage was about 75 cents to a dollar and hour.
Louis

Water pump cover is 2 1/8" x 16 Left Hand thread.

[JordanSewruk]

Does anyone know where I could purchase a gas cap (has hex nut for the fuel filter on the bottom) for my ke4? Thanks in advance.

[green-thumbs]

KE4 & Mark 7 outboards sold well and are fairly common at swap meets. A parts motor might with a good tank is likely to be a better investment than a special purpse tap AND the time and effort to remove dents.

Tap for tank with the small filter is 1-1/8″x 18 National Standard Mercury  Part # M-60-5070  Bottom filter tap size is 1/8″ National Pipe Taper.

Tap for tank with large hexagonal filter is 1-3/16″x 16 National Standard for BOTH filter and filler neck. Mercury Part # M-60-5071

National Standard is an obsolete name for Unified National Standard. Each trade and industry as it developed attempted to create a standard for fasteners. As a result we have to identify threads and fasteners. Metric has been adopted for things made in last 50 years…just another addition to the complex brew of threads and fasteners.

Louis

 

 

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