Topic: Head oil passages

[upperlake04]

Checking over the top end of a 1978 750F3 engine.  I am a little spooked after seeing what affect crud in the oil restrictors will have on moving parts in the head and want to get it right before reassembly.
   
   In the top front of the bottom end case there are two wells which appear to be part of the oil drains from the head,  each have two holes in the bottom that are partially separated by a wall.  No idea where they drain to.  In each well, the hole closest to the centerline of the engine has a small oval metal wafer over it. The wafers (8x10mm)(5/16x3/8) are curved like a shield or pringle potato chip and are sized to stand on end, leaning into a corner  of the rectangular well. One was resting with its bottom in the center of the hole and the other, leaning a bit more, covered the hole. Both concave side up. Seems the oil flow must be different on each drain.

   These look like a designers afterthought. Anybody have  ideas on -
      - why these are here?
      -what is the correct placement?

[750goes]

I'll be game.

I don't think they belong in there... looks like something fell in your motor, if one was up and one was down blocking the hole??

[CB750R]

from first glance they look like the foil on the lid of an oil bottle, but from where they are located it would be dam near impossible with our oil tanks for them to make a journey like that throught the engine!!!  Or at least I think it would!! I don't recall seeing those with my 74 engine, I'll have to go look at my 77 to see if they have em! My guess is not likely though

[6adan]

Not sure about these but some diesel engines I have worked on had a heavy wire in some passages to keep crud from building up. You might parts book before you leave them out .Dannie

[scondon]

Oil should go down both sides of the opening. I can only guess that someone thought that because the inner studs(oil returns) are blocked off on the F3 they should also plug the drain. With the motor assembled there is no way those wafers could "migrate" there. They had to be placed, but I can see no reason.

[jtb]

Upper, I just got the cylinders off of my F2 motor last night.  There is nothing like that in it.

John

[upperlake04]

Dannie - geez man - what a good idea - check with the LHD to see if they are real parts. Looked at the microfiche diagrams for F engines with the service manager this afternoon. Couldn't see anything that looked like these wafers. He had never heard of this before and couldn't think of an explanation either.

Scondan - right- the wafers couldn't migrate from above because the top of the oil passageway is capped with a nut and the drain hole from the front of the head is too small to admit it. Agree with you someone put them there for some reason. Your theory why is the best so far.

jtb - thanks for that. The parts diagram included F2s also so looks like your engine is correct there. Can you tell if it has been opened before?
 
Thanks for your time guys - I'm leaning toward flipping them over my shoulder.

[Sam Green Racing]

Sell them on ebay, they may be rare sandcast thingies 

[Bob Wessner]

Thanks for your time guys - I'm leaning toward flipping them over my shoulder.

Save them for a tailgater.  Oh, that's another thread. 

[jtb]

Upper,  I don't believe anyone has been in it before.

John

[750goes]

Pull em and Chuck em.

Some nasty Honda apprentice many years ago had a bad morning assembling Motors and decided he would give his boss some #$%*, therefore he being famous for his feng shui and oriental positioning, placed some pressed metal off cuts into this engine, just so one day all westerners could be beguiled and marvel at his ENGINUITY..