The washer runs for hours and only about 6 minutes comes off the timer

Check the filters in both ends of the hoses. If they are clogged, it will throw the timer off. If it figures on 2 minutes to fill but it actually takes 6 or 7 minutes, the timer won't be accurate.

A mechanical timer defrost cycle is approximately 23 minutes, and it occurs at intervals of between 6 and 12 hours depending on the timer. If it does not come out of the defrost cycle on it's own, your timer can be bad. Be sure the heater actually comes on while in defrost. Also be sure the evaporator (freezer) fan is on when in the cooling cycle. If both of these occur. Replace the timer. It's important that the timer be replaced with an identicle timer.....6 hour for 6 hour, and that the 4 numbers by the electrical contacts be in the same order. In addition, if there is a loose wire from the timer motor with a slotted contact at the end, make sure you follow the instructions as to where it goes.

Timer is not identified.
Add a comment with in-focus photo of timer posted on flickr, or describe all details about the timer for possible help.

240 minute timer could be a cycle timer that repeats timing cycle each 4 hours.

Tork 8000 series cycle timers have 6 minute to 1 hour
http://waterheatertimer.org/Tork-timers-and-manuals.html#8000
Intermatic cycle timers range from 10 minutes to 4 hours
http://www.intermatic.com/products/ec%204%20layer/mechanical%20time%20switches/specialty%20time%20switches/c8800%20short%20range%20cycle%20timers.aspx
Adjustable cycle timers, percentage cycle timers have variable time settings that span 1 to 24 hours.
http://waterheatertimer.org/Paragon-timers-and-manuals.html#JW
http://www.grainger.com/Grainger/wwg/search.shtml?searchQuery=cycle+timer&op=search&Ntt=cycle+timer&N=0&sst=subset

Open following link to identify TM311 timer:
http://www.amazon.com/Intermatic-TN311C-Heavy-Grounded-Timer/dp/B00002N5FO

1) First of all, you would need more turquoise 107TN222 ON and red 107TN221 OFF trippers.

2) BUT big problem is that TN311 time dial is divided into half-hour segments, so minimum on-off is probably 1 hour since it takes 2 trippers for on-off cycle, and width of 2 trippers is same width as 1 hour.

3) Open following link for plug-in timers with 15 minute segments shows Woods 49664 & Stanley 31192 & Sylvania SA110
http://waterheatertimer.org/Woods-timers-and-manuals.html#49664

4) Notice the 49664 dial, that each hour is represented by 4 segments. This says timer on-off period is 15 minutes.

To set this timer, you would pull up all segments around the dial, and then push down 1 segment for each hour that you want timer to turn on for 15 minutes.

5) TN311 has 3 prong grounded outlet, Woods 49664 has 2-prong outlet.

6) Stanley 31192 timer and Sylvania SA110 have 3-prong grounded outlets and 15 minute intervals.

7) You cannot accomplish 15 minutes intervals for 12 periods a day with programmable digital timer.
Most digital timers allow 1 minute program times, but are limited to 6 or 7 programs, and not the 12 separate on-off periods needed for your project.

Add a comment for more free help.
Also take advantage of fixya expert assistance live.
For a price, expert works with you while you work on timer or any do-it-yourself project.
Fixya is always less expensive than a service call.

Identify timer on following page:
http://waterheatertimer.org/Woods-timers-and-manuals.html

Page shows instructions and troubleshooting.

That being said, if your timer has a dial with 2 4 6 8, then following instructions probably apply:

Timer turns on automatically at dusk,
Rotate dial to select when timer will turn off.
In your case, rotate dial to 6, and then timer will turn off 6 hours later.

Make sure to keep timer turned away from lights, or where car lights might reach photo-eye located on front of timer.
If timer is exposed to light, it will turn OFF, and then blink back ON few minutes later.
When timer turns ON again, the 6 hour countdown starts over.

You posted under a photo that looks like Woods 49063 or GE 28441
Link below shows this particular timer with manuals for each:
http://waterheatertimer.org/Woods-timers-and-manuals.html#Oval

If your timer does not show on link above, add a comment with as much description as you have, with button locations and color and purpose of timer.

To program the GE timer:
1) Set current time
Press and hold Time button: and then push hour and MIN button to set current hour and current minute.

2) To program:
Press and hold PROG button for 1 second
Prog 1 ON will display
This is program1 ON
Press hour button and MIN button to set program1 ON hour and minute

Press and hold PROG button for 1 second
Prog 1 OFF will display
This is program1 OFF
Press hour button and MIN to set program1 OFF hour and minute

Press and hold PROG button for 1 second
Prog 2 ON will display
This is program1 ON
Press hour button and MIN to set program1 ON hour and minute

Repeat steps to program up to 6 different ON-OFF programs
When programming is finished, press TIME button to return to current time.

3) Set MODE
Press mode button once and ON displays, this means light is ON
Press mode button again and OFF displays, this means light is OFF
Press mode button once and nothing displays, this means timer programs will run as you set them

Manual:
http://waterheatertimer.org/pdf/Woods-59203.pdf
59203 plug-in timer: your outdoor lights have to plug into side of timer.

If you want a timer to replace outdoor light switch: buy in-wall timer Aube T1032 or Lowes sells Utilitec 0192773.
http://waterheatertimer.org/Programmable.html#Aube
Add a comment for more help with in-wall.

Here are instructions for 59203 plug-in timer:
Plug in the timer until battery is charged.
Unplug timer so you can program easily.
Press R reset button with paper clip to clear.

Set the time of day:
Press and hold clock button
Press hour button until current hour shows
Press minute button until current minute shows
Press day button until current day shows.
Release clock button

Program review:
Write out ON-off schedule showing hours minutes and days
For example: timer turns ON 6:00 pm all days of week.
Timer turns OFF 1:00 am all days of week.
First step: Set program1 ON > hour, minute, and day.
Next step: Set program1 OFF > hour, minute, and day

If needed, go to next step: Set program2 ON > hour, minute, and day
Next: Set program2 OFF > hour, minute, and day

How to program timer for ON at 6:00 pm and OFF at 1:00 am all days of week:
Step 1: Press PROGRAM button until display shows 1 ON (this is program1 ON)
Press hour button until 6 pm shows
Press minute button until :00 shows
Press day button until all days of week show (MO TU WE TH FR SA SU)

Step 2: Press PROGRAM button until display shows 1 OFF (this is program1 OFF)
Press hour button until 1 am shows
Press minute button until :00 shows
Press day button until all days of week show (MO TU WE TH FR SA SU)

If you want to set another program, you will repeat same steps for program2
Press PROGRAM button until display shows 2 ON

If you are done programming, press clock button
Press ON/AUTO/OFF button until AUTO displays

Good day,
The decision as what the time interval of a timer should be is determined by engineers and field tests.
There is more to the timer than interval. Timers are usually listed as 8 hours 21 minutes, 8 hours 30 minutes ect. The minutes is used to designate the time the control stays in defrost.
A general rule is if the interval is longer, the minutes in the defrost cycle is extended to compensate.
Other factors come into play such as the wattage of the defrost heaters and the defrost thermostat temperature.

The trend today, with timers is to extend the interval to make the machine more energy efficient.

There is never an issue to defrost more often then the original, but it will run the heaters more often, and cause increased operating cost and shortened heater life.
The short and long of it is you can use a 6 hour timer in any machine if the timer motor wiring is the same and the duration is long enough, but with the costs listed above.

replace timer

Your defrost timer may be malfunctioning and staying in defrost mode too long. It is mechanical and the timer can be sticking or slipping. I think your timer is behind the kick panel on the front bottom of the freezer/fridge. You can turn the timer till everything cut off and watch to see if it runs. Everything should come back on in approx 20 minutes. You can test it with a ohm meter. See how here> How to check stuff> http://www.acmehowto.com/howto/appliance/refrigerator/refrigerator.php