f.5 ENGINE (1 Viewer)

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Keene, Ca.
I was given a spare engine (F.5) to replace the low compression F that's in my FJ40. I pulled the oil pan off yesterday to replace the front and aft seals and found some damage. The first thing I noticed were the cam lobes...

000_0513.jpg


I really don't know the history of the engine other than it was pulled about 10 years ago for a V8 conversion, and that it ran fine before that. Last night I pulled the pistons and 1,2 and 5 had broken top rings. The rest looked ok other than the dark color.

000_0511.jpg


The connecting rod bearings looked like they've over-temped or over-sped (lack of oil?) and the cylinder walls have some damage.

000_0515.jpg


000_0509.jpg


That groove at the 2:00 position is deep enough to catch your fingernail in. The engine was bored .30 over at some time (I think) so I'm trying to determine if this thing is worth rebuilding. I know these are supposed to be good engines but the engine in the '40 has low compression (#5 exhaust valve) and was coming out anyways.
So, here's my dilemma. Valve job on the F engine or rebuild the F.5? The spare came without a carb so I'd have to run the Weber 32/36.

100_2157.jpg


Pics on windshield are for inspiration only. I'm getting a better understanding on why these are called F engines. This thing is really F'd up!

Pat
 
Last edited:
Given; so you are not out any money.


Good.


Figure out what the engine block has been cut to, and if you can bore it out and clean up that groove…..

-OR-

Find a running 2F or install a V8 and do not look back.





BTW, that camshaft is not something I would use, and those rod bearings do not really look that bad, and would likely run a long time with proper lubrication.


:beer:
 
A proper rebuild on the old .5 my 2c, big dollar though. Oversized pistons can be found for the punch out. Better to rebuild the .5 than throw money at the f (keep in mind, rebuilding the head will put more pressure on the rings). The .5 has better oiling higher compression and more torque than hp. The head is unique to that engine, can't be used on motors prior to it. Bonus, the 32/36 will still work.
 
I have a f.5 can part out to you. The short block as been rebuilt, but the long block is a 100K something engine. Ran when pulled too. The only thing I want to keep is the valve springs. It would be easy enough to ship the parts you need instead of the entire engine. Let me know (I could even ship the top end as a unit ifneed be. It would make a quick and cheap rebuild option for you.

Mark of Mark's off-road wanted it, but he hasn't contacted me about it. So unless he chimes in, you can take what ever parts you need at a very good price.
 
I have a f.5 can part out to you. The short block as been rebuilt, but the long block is a 100K something engine. Ran when pulled too. The only thing I want to keep is the valve springs. It would be easy enough to ship the parts you need instead of the entire engine. Let me know (I could even ship the top end as a unit ifneed be. It would make a quick and cheap rebuild option for you.

Mark of Mark's off-road wanted it, but he hasn't contacted me about it. So unless he chimes in, you can take what ever parts you need at a very good price.

Slickrock,
I'm in the Tehachapi area, so a pickup would be easy. I'll send you a PM.

Pat
 

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