Help with F Engine (1 Viewer)

[hairy_apple]

I bought a F engine a few months ago from a member here. I didn't realize that there was an earlier style head for the round early intake and exhaust. Its not going to work for my 55... can I replace the head with the later head so that the later style intake will bolt up? The early motor I have is rebuilt and I don't really want to get rid of it for a newer style, can I use the valves, rockers, ect from the rebuilt one and put all the new parts into the differant style head?

HELP! I'm really depressed I did something so dumb... I was a day away from putting it into my cruiser and now I'm not sure how long it will be before I can get my pig running.

 

[mruff]

When you say early f or you referring to a 1 f ? What year is your motor?

 

[hairy_apple]

Yeah, the 1F. The motor I THINK he said came from a 67. I will take a few pictures tomorrow to help explain my issue.

 

[FJ40Jim]

It is definitely better to use the 12-port head and associated manifolds.
If the FJ55 block has flattop pistons, then 55 head will bolt on the 1967 block and give a reasonable compression ratio. If pulling the head off the 55 reveals domed pistons, then putting the 55 head on the early flattop block will give something in the 6:1 compression range. It will run, but power/efficiency will be noticeably down.

HTH

 

[hairy_apple]

OK, sounds good. I pull the head and see what I find. Hopfully I luck out. Otherwise I guess I'll sell my motor and see if I can't find a newer F for the 55. Thanks.

 

[hairy_apple]

OK, pistons are flat. So my next question is... assuming either of the 12 port heads I have can be saved.. both are pretty rusty... can I use the parts from the older one and just swap them into the 12 port? Or are the parts not going to be interchangeable. The valves I understand will need to be replaced to make sure they are seated to the new head, but what about the rest... a bunch of new parts I hate to got to waste (not to mention I can't really afford all new parts for the new head).

 

[FJ40Jim]

Shouldn't need to buy anything, especially with 2 heads' worth of valves & springs.

If I was doing this on a budget, I would pop all the valves out of both heads, discard any obviously bad ones. Look at both castings to see if any of the exh seats are terribly sunk, discarding head w/ worse seats. Take best head casting and all valves & springs to machine shop, get a valve job & new seals. The new seals will be in the head gasket kit. clean head & valve job<=$150. Head gasket set @ rockauto =$50.

 

[Living in the Past]

When you say early f or you referring to a 1 f ? What year is your motor?

Not sure what a 1f is? There were five versions of F engines in the US but no 1F. The F120 in the early FJ25s. The later FJ25 and FJ40 until the 68 model had a F135. Then the F145 in the 68 thru the 71 models. 72/73 had a F155 with the old oiling system. The 74 had a F155 with a improved oiling system which was also in the 2F. This was still a F engine and not a F1.5. It it did not have the 2F oiling system but instead the 2f had a late F engine oiling system since it was first.

Don't know what year engine is in the 55 now? But if it's from a 74 or newer model the oiling system to the rockers will be different and wouldn't work. 73 and older used a copper tube to feed the rockers after that it was machined into the head.

 

[motovate]

I just ran across this thread and was wondering if you might be able to help identify the type of "F" engine I have. I am pretty sure it is a F not a 2F - well sort of sure! I have found a couple of sites that list engine numbers to ID the engine but nothing to match what I find. I also have a question on how the "F" oil pressure system works since I have read where it is not too good??

I have a new to me 1966 FJ 40 , 3 speed- it is clear the engine has been apart at one time and has been modified. The Block serial # on the pass side is 518254 and on the front of the block on the driver side I find #1141 60032.

The Valve cover is Aluminum and kind of rounded - looks like a 2F cover and I understand this is a common modification, it has an aluminum intake manifold and also looks like a 2F and has been converted to a Holley 2 BBL carb. It also has a screw on oil filter on the pass side of the engine located between the distributor and the fuel pump and I can't tell for sure but I don't believe there is an oil pressure regulator(?). There is a PVC connection coming out of the front side cover on the Pass side which is connected to the intake manifold. It starts right up and idles good and seems to have good power. I've run it around some - 4-5 miles worth a couple of time on the back roads where I live (out in the county - low population dirt roads).

I'm not sure about the oil pressure. With the existing - I believe stock oil pressure sender it shows some oil pressure after a bit on start up then moves up a bit but barely into the normal range. I pulled the sending unit and kind of cleaned it out with brake cleaner and WD40. I also started it up to see if oil would come out of the hole and it puked it out real good! I changed the oil and filter since what came out was real black and ordered a new sending unit from Specter just to be sure and it did not register pressure at all so I put the old one back in and it showed the same as before - low but pressure going up to barely normal then dropping down. then it dropped off completely but kept running good - no rattling noises - seems normal except for showing no pressure. I'm kind of spooked!

So if you can help with IDing the engine via serial number and maybe some info on "F" oiling system/pressure I'd appreciate it. If it helps I can send some photos.

Not sure what a 1f is? There were five versions of F engines in the US but no 1F. The F120 in the early FJ25s. The later FJ25 and FJ40 until the 68 model had a F135. Then the F145 in the 68 thru the 71 models. 72/73 had a F155 with the old oiling system. The 74 had a F155 with a improved oiling system which was also in the 2F. This was still a F engine and not a F1.5. It it did not have the 2F oiling system but instead the 2f had a late F engine oiling system since it was first.

Don't know what year engine is in the 55 now? But if it's from a 74 or newer model the oiling system to the rockers will be different and wouldn't work. 73 and older used a copper tube to feed the rockers after that it was machined into the head.