I have never had luck finding one specifically for the 20R, but when I put my 20R back together, this was a great resource: http://www.bluebassdesign.com/boonin/carb_faq/
There are a few differences between the 22R and the 20R, but it should be close enough for you to get an idea.
The best one i have every seen is "a193 clymer publications"
Follow the link and buy the bookhttp://www.themotorbookstore.com/toyota-pickup.html
You may want to try www.autozone.com they may have the diagram for a truck of that year.
You may want to try www.autozone.com they may have the diagram for a truck of that year.
Go to auto Zone and get a Haynes manual and look in the emissions section for your year.
If it's fuel related it's on the right side of your carburetor held in place by 3 screws & avacuum line.
The Toyota 1978 20R Emission Control Repair Manual, pub 98268 is still available from Toyota parts, is about $12 and covers all versions of 1978 20R engine emission controls and vacuum lines. You have to have your dealer order it by part number.
0.18 or the thickness of a business card
no it will not the pistons are diffrent the 20r has domw pistons and the 22re has flat top pistons
sign up for autozone and use there repair guides or ask the guys on the all auto forums www.the-engine-source.com they will post them promptly hope this helps
Your local library should have Haynes or Chilton's Manuals. If not, you can buy a Haynes manual for your specific truck at your local Kragen's, Checker, Pep Boys, Napa, etc.
It can be: depends on the value of r.