What engine is this?

Joined
May 19, 2005
Messages
7
I am working on a friends FJ40. He doesn't know anything about engines, etc., so I am trying to figure this out. It is a 1972 fj40 but he was told when he bought it that the engine was from a 1974 fj40. Long story short, the head cracked and needs to be replaced. After some long searching here I still can't figure out if this is an F head or a 2F head. It has the F valve cover, a one piece rocker arm assembly, and did not have any copper tube running up to the head. The block also does not have any tube coming out by the #3 cylinder either. Is this a transition engine that I have seen some posts about? I don't have the head right now because it is at the shop. I can run and get it if I must get codes. Does anyone else have some pictures I could see so I could compare to what I have. Hope that is enough info. I don't know very much about these trucks.
Thanks,
Dan
 
Joined
Jan 22, 2003
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Kansastitty
If the oil filter is mounted to the block on the pass side it may very well be a '74 "F and a half" transition motor. I think you can use an early 2F head, but it will lower the compression a little. You can also look between the starter and the dipstick for a flat milled area which would have the engine# on it. That will confirm. http://www.sor.com/fengine.html

GL

Ed
 
Joined
May 19, 2005
Messages
7
Engine stamp

Ed,
Thanks for the help. The stamping is F 511306. According to that site you sent me it should have been built somewhere between Sept of 73 and May of 74, which would make it an F, correct? The oil filter is on the passenger side and mounted vertically. There is no tube coming up from the lifter valley for oil. So do I have an F? Just want to know what head I should be looking for. Thanks again to anyone who can help.
Dan

Degnol said:
If the oil filter is mounted to the block on the pass side it may very well be a '74 "F and a half" transition motor. I think you can use an early 2F head, but it will lower the compression a little. You can also look between the starter and the dipstick for a flat milled area which would have the engine# on it. That will confirm. http://www.sor.com/fengine.html

GL

Ed
 
Joined
Jan 22, 2003
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8,118
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Kansastitty
Yes you have an "F", but a strange one. You can't use the older F head, because it oils differently, but if you use a head from a 2F, you will lower compression, by how much and does it make a "feelable" difference, I don't know. I've heard of some owners using the head off a motor like yours and putting it on a 2F to raise compression.

I have the same motor, so I'm not knocking it. I think that head was made just that one production year and nothing else will fit without changing something. Actually, you could use a 2F head and shave it .040 and probably be good with it.

GL

Ed
 

CruisinGA

 
 
Joined
Mar 27, 2003
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Georgia Tech
Ed is spot on, Dan.


Another oddball 3F/2 owner here. :D You shouldn't have much trouble finding a '74 head, unless you are in a hurry.
 
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