For some reason, I can't seem to locate the information on the position of the rear camshaft bushing. They have a notch, I assume for oiling, but the old one in my block has the notch facing down. I would think it should be on top so as to catch the oil being splashed around...but I've been wrong before!
Which way is the notch supposed to go?
The notch should be up.
George, the notch goes up on the side of the of the pushrods. I believe the notch allows clearance for the rearmost pushrod.
Well, that would explain why there's a big "chunk" missing on one side. Looks like a new bronze replacement is in order......
Ford service book, page 70 par 256
George, hope the quality of the bushing is better to day vice 15 years ago. The replacement I received was brass...not bronze and did not have the internal oil grove like original. After 5 yrs. running, I replaced the camshaft and found the replacement bushing seized on the camshaft and spinning in the block. No damage.....hunted thru my stash and replaced it with a used original bronze bushing. All has been good for the last 10 years. I also add an oil hole and counter sink the hole on the flywheel side of the block for extra oil.
Thanks everyone.......the existing bushing in my block (1918) is iron and probably a replacement, as it's evident that the engine has been overhauled many years ago. It's pressed into the block with enough clearance left for the lifter and the only "notch" is a broken out chunk on the bottom of the bush.
Despite the slight damage and the missing bit, it's still a good running fit with lots of bearing surface and I'm tempted to leave it. I'll address the issue after all the other work it completed.
Oh, and I finally found the information (thanks Frank). It was located in the engine rebuild section and not in the camshaft bearing section where I thought it would be.
Original rear cam bushings were cast iron.
I do not know what year Ford changed the cam bushing material from Bronze to Cast Iron. Bronze is correct for my 1913 engine.
You can't buy a rear T cam bushing from a vender that will work!
We make our bushings out of old triple gear bushings, that have not spun in the gear.
The O.D. of the bushing is correct.
The length is correct.
The I.D. is about .050 thousandths smaller so you can get the .002-00 fit you have to have, and no less, and no more then .002-25 when you align bore.
You cut in the notch, and oil groove goes the full length of the bushing.
The notch is not for lifter clearance, it is for catching oil for the groove.
The bushing is seated even to the block's bushing hole, as any more the cam won't go all the way home.
Stephan, how are things going? Gen OK?
Thanks for those great pics Herm. The location of the bushing was another question I had, as mine extends into the block a bit. I assume the front and middle bearings actually control the cam's position......is that correct?
The front only, sets the cam position, as it has the thrust.
Hal, the generator is working great. Thanks again for the armature. I'm working on the rear axle for the 25 touring now.
I have never seen a worn out rear cam bushing, Neither cast iron or bronze. Sure they wear but they never wear out. We make ours using SAE660 bearing bronze with the notch and oil grove. We make both standard size and 0.010 under for worn rear cam bearings. Have never had a problem with our bushings.