1972 FJ40 belt drive

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Feb 23, 2015
I have a 1972 FJ40 and I am having a little trouble with the belt setup on it. My alternator is on the passenger side of the motor and I believe that there used to be a air pump located on the drivers side of the block. Right now I am having to run a belt straight from my crank pulley to the water pump. What I'd like to know is there a idler pulley setup that I can run to get proper tension on my belt going from the crank to the water pump? The alternator belt is fine because the factory bracket has adjustment in it.
Welcome to MUD Jake!

You only need one belt for Alternator X Crank X Water Pump and use the Alt pulley to adjust the belt.
I would do that but the pulleys do not line up. My crank pulley has two grooves in it and the water pump pulley only has one groove. The alternator runs off of the outer groove on the crank pulley and the water pump runs off of the inner groove.
how about getting a 2 groove water pump pulley?
maybe a pic would help.
The simple fix is to change the water pump pulley so all the pulleys are properly aligned. The water pump pulley should have two grooves.
I made a home built idler for mine when I had that problem, you might do a search, I'm sure someone made on at one time to replace the air pump pully. I believe FJ40 jim used to make a kit for them, best, Larry
Where would I get a two groove water pump pulley that would line up?
Take a pic of your setup please.

The 72 had the Alternator on the Drivers side. No smog pump on a 72.
I will Take a picture of it when I get home. I believe that cvf has a pulley that will work but any input would be greatly appreciated.
Well, depending on how the alternator was moved, no "stock" pulley will line up properly..

Later factory brackets can easily be used to relocate the alternator, which is probably what happened to your setup.
My crank pulley has two grooves in it and the water pump pulley only has one. The outer groove of the crank pulley lines up with the alternator perfectly. If the water pump pulley had two grooves in it I could run the it off of the same belt as the alternator correct? I believe that cvf has this pulley. There is some type of Mount down on the right side of the motor and I'm not sure what's supposed to go there. But I ordered the alternator in the pictures from advanced auto and it will not go on the mount on the right side. And I believe that what is the factory pigtail for the alternator is located on the passenger side of the motor.
That sure looks liek the stock Alt mount to me.. It's easy to relocate tho..
Maybe I am jumping in late here but is this an F or 2F? I did not think the 2F Motors came out until 74 or 75. The F the Alt is on the drivers side, the 2F is the passenger side. I had engine issues on my 12/72 and picked up a 2F as a replacement. It looks almost like you are mixing parts between these two engines to me. I added some pics for your viewing pleasure. The First is my F with the carb etc... installed. The second is the Donor 2F before I began rebuilding it. Notice the Alternator is on the passenger side for the 2F. Hope this helps.

Carb installed-2.jpg

Donor Engine Before re-build (7).JPG
the "Carb installed-2" pic is a F155.

the Donor Engine before Rebuild looks to be a 2F from a 60 series.

Neither one appears to be the motor that is in the pics you have posted already..

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