All Small Six Reassembly 200 six---2 issues, no oil to rockers, I broke a head bolt

This relates to all small sixes
N

nearGettysburg

Active member
Subscriber
Assembly has gone along pretty well---ring gaps and side clearances OK, con rod side clearances OK. Main and rod bearing clearances OK--by OK, I mean well within the oem specs from the FSM.
I got the cam and lifters in and used the oil pump shaft and a cordless drill to pre-lube. ,I saw over 20 psi on a mechanical gauge installed at the left side of the block near the end.
What I didn't see was any oil coming up the head bolt hole for the rocker shaft. Does it need more pressure to pump up there? Seems to me I should be seeing something.
Also three of the original head bolts seemed a little "soft" as I tightened them to the 2nd round spec of 55 ft lbs---one actually broke before reaching 55 ft lbs.
Are ARP head bolts available, or is there a better way?
 
Oil pressure is fine, it might take a some time for oil to get to rocker shaft, keep going. If after a minute or so you still dont have any oil, you may have sludge in the passage. As to head bolt breakage, thats unusual, check that the bolts are correct, should be grade 8. (6 stripes on the head) Grade 5 (3 stripes) might break at that torque, also check they have not bottomed in the hole, perhaps you should run a tap down each hole to clear out any muck that might get in there. There is nothing wrong with ford factory bolts. BTW Im NOT familular with USA blocks, all our Australian engines had adjustable rockers and were fed by the back bolt hole.
 
Thanks--These head bolts have the 6 marks on the head. I tapped every hole before i began reassembly. I could feel that bolt and 2 others--"stretch" as I tightened them. I will be replacing all of them.
I have run the oil pump with the drill for a total of over 5 minutes and saw no oil coming up the head bolt hole before i installed the head. I "thought" I had run a brush through all the oil passages and blown them out with air. I may have to take another look.
This is the time to do it.
 
If the two holes in the rear cam bearing are not lined up properly it will cause no oil to come out of the oil port by the driver side rear head bolt that oils the rockers buy way of the kidney bean groove in the head over to the bolt hole in the head and then rockers. Make sure that your torque wrench is accurate.
Do not ask how I know this. ;)
 
Those bolts have been stretched beyond use so you are wise to replace them. As drag-200stang said, cam bearing alignment to the oil slots is probably first culprit, also possible on a heavily milled head that the transfer groove is gone or almost gone. You can regroove that with a Dremel if needed.
 
Last edited:
I was afraid that the answer would involve the cam bearings--just a feeling.
I will try blowing compressed air first, but I bet my "assembly" will be turning back into "disassembly" Oh well---THIS is the time to know these things; it is why we do so many checks along the way.
I think the engine will sit for a few days as i work on the underside of the body. I have the rear axle out so its easier to clean the underbody. Once I wire brush the axle and repaint it and the springs and shackles and install be spring bushings, I can re-install the axle and move on with new brake and gas lines. Lots to do.
 
mustang6 said:
Those bolts have been stretched beyond use so you are wise to replace them. As drag-200stang said, cam bearing alignment to the oil slots is probably first culprit, also possible on a heavily milled head that the transfer groove is gone or almost gone. You can regroove that with a Dremel if needed.
Click to expand...
Is there any chance that a long drill bit could be used to open up the cam bearing? ( Obviously AFTER removing the camshaft.)
Or is complete R&R of the cam bearing my only hope?
 
drag-200stang said:
If the two holes in the rear cam bearing are not lined up properly it will cause no oil to come out of the oil port by the driver side rear head bolt that oils the rockers buy way of the kidney bean groove in the head over to the bolt hole in the head and then rockers. Make sure that your torque wrench is accurate.
Do not ask how I know this. ;)
Click to expand...
That's why I really like a beam torque wrench.
You can rough calibrate them any time with just a (relatively) immovable bolt, a weight on a wire, and a measuring tape.
 
Pardon my ignorance, but per this blog, in my 200, there was an oil passage that needed to be plugged, feeding oil to the head and original rockers. I have yella terra rollers, so plugged the passage on the rear of deck. Are there two passages that feed the original rockers?
 
When I primed my 200, I had to put the distributor in w/o the gear to get the oil to the rockers. Otherwise, the oil would bleed out the distributor oiling hole.
 
Hi, the ARP head bolts are really nice. I seem to remember that early Ford head bolts have thick shoulders, and later ones had a thinner shoulder. Back in the 70's, we used to grind three thin flats on the left rear head bolt to give the oil more space between the bolt and the head. I have never heard of these head bolts softening and snapping. Good luck
 
vssman said:
When I primed my 200, I had to put the distributor in w/o the gear to get the oil to the rockers. Otherwise, the oil would bleed out the distributor oiling hole.
Click to expand...
So with the distributor in, how did you turn the oil pump?🤔
Can’t be the starter cus the gear was off
 
DON said:
Pardon my ignorance, but per this blog, in my 200, there was an oil passage that needed to be plugged, feeding oil to the head and original rockers. I have yella terra rollers, so plugged the passage on the rear of deck. Are there two passages that feed the original rockers?
Click to expand...
There is two holes in the rear cam bearing one goes to the main bearing , that is where that cam bearing and around a grove in the the cam journal out the second cam bearing hole to a passage up to the deck by the drivers side bolt that oils eventually the rockers that is the one that gets plugged, only one.
 
I just looked at a block in the dark with a small adjustable beam flashlight and I could see that the cam bearing top hole was lined up in the block. Try that, it is a start, It is possible the one you cannot see is not lined up among other things.
 
Last edited:
Thanks for the responses---it is good not to feel all alone in this.
I am taking a break from the engine for a couple of days. My car needs a lot of work in several areas and I have ADHD, so sometimes it is best to just move to another part of the project. I have removed the rear axle and I am cleaning up the underbody and the axle and springs. I want to install new spring bushings and get the axle back in place so I can install the entirely new ( original) brake system--shoes, hardware, wheel cylinders, flex hoses and steel lines---THEN I can return to the engine and solve that issue--
Thanks, again.
 
Does the crankshaft need to be turning for the oil holes to line up and feed the oil up to the rocker shaft? I am going to manually turn the engine and see if there is a spot when the oil does flow.
 
nearGettysburg said:
Does the crankshaft need to be turning for the oil holes to line up and feed the oil up to the rocker shaft? I am going to manually turn the engine and see if there is a spot when the oil does flow.
Click to expand...
No, it does not. Next time you prime the engine, look closely down the distributor hole and see if you have oil running out of the galley. I had the exact same issue and had to prime with the distributor in place (gear removed) as I noted above. Good luck.
 
vssman said:
No, it does not. Next time you prime the engine, look closely down the distributor hole and see if you have oil running out of the galley. I had the exact same issue and had to prime with the distributor in place (gear removed) as I noted above. Good luck.
Click to expand...
I think this is "the answer". I did see a lot of oil flowing all around the distributor opening. I was confused by what I saw. Now I think I understand--the distributor actually sits in that pressurized main oil galley. That would explain the length of the machined base of the distributor shaft--we all know Ford ( or nobody, actually) would "waste" machining time on a part that did not require it.
Looks like i will be removing the distributor drive gear off the shaft of an extra distributor and try priming the engine that way.
Thanks--You provided an insight that agreed with something I had seen, but failed to include in my initial posting because I didn't understand the significance of what I was seeing. Now it is beginning to make sense.
Are there different camshaft oiling designs for this engine? I "thought" I had read about the rear bearing being cross-drilled, yet the "extra" cam I have is grove and only at the rear bearing.
 
You must log in or register to reply here.
Back
Top