I'm having a problem with a straight six I just put back together. I'm not used to these fancy cars with ohv engines. I had the top end off of this chevy straight six. I did a major overhaul of the head. Got it all back together. Fired right up. But it's not getting any oil on the top end. I've maybe run it 10-20 seconds. It's got oil pressure on the gauge. I read about the head bolt with the hole in it. I checked all of those. None of them look special. Did I put the freaking head gasket on wrong? I suppose there is a first for everything.... Just wanna see if there is anything else I should check before I tear the head back off? Signed Feeling stupid. Sent from my SM-G900T using The H.A.M.B. mobile app
Is it possible that it takes longer than 10-20 seconds for oil to start coming out of the small holes in the tops of the rocker arms ?
Take the dizzy out and spin the oil pump with a big screwdriver blade in a drill. Don't fire that engine up without some oil up top!!!
Common 235 issue when they have wear. The oil can get as high as the top of head, then just quite can go higher to the rocker shafts. I've watched that happen. on a old beater, you can externally pipe oil to the shafts, but you need to restrict it, so pressure does not drop elsewhere. The new pipe does not just drip, it is plumbed in
I should also mention I have turned it over with the starter a lot. Enough to get oil pressure on the gauge in the dash. Sent from my SM-G900T using The H.A.M.B. mobile app
This is kinda my fear. It's an old engine for sure. The rocker shaft and rockers were hammered. I figured it was just old and worn out. It's got great compression. So did a overhaul of the head and cleaned everything up. I did coat and pour oil all over the them before I fired it up and ran it. And I have turned it over a ton without the ignition hooked up. Not getting any oil flow. Sent from my SM-G900T using The H.A.M.B. mobile app
If rockers were hand oiled, you can run it in shop as long as you want. Many ancient cars were hand oiled. An oil can bracket on firewall I don't recall which part I took off for the visual flow to the rocker shaft. It was something easy. I ran it at higher rpm, and the oil came right up level in the head outlet, but no farther, I had some sort of T handle in-line shutoff, so I could set the lowest flow and still be OK. Then I snugged down the packing nut on T valve, so it stayed there. I pulled the oil from maybe the p***enger side? I think? .
Only certain head/block combinations need the drilled head bolt. It's located in the center hole on the p***enger's side, and the bolt has a slot in the top resembling one for a big common-blade screwdriver. Early-production heads have an oil line feeding the rocker arms, while later ones use a drilled oil p***ageway in the block and a corresponding one in the head. Certain combinations use the drilled bolt to complete the oil circuit to the rocker arms. Jerry (stolen from chevy talk hope it gives some clues)
There are 4 different rocker arms that need to be put back on the shafts in the proper order and the shafts are blocked at one end that has to go on the outer ends. http://chevy.oldcarmanualproject.com/shop/1954truck/54ctsm0611.html
I have a 57 235 that never got oil to the head after rebuilding and I think it had all 57 parts,I ended up grinding a slot through that center head bolt to get oil and eventually fornd a drilled head bolt in a junkyard. I never heard this motor run before I bought it and it needs to come apart so I want to see what went wrong.
A couple of thoughts/questions. When you say you "overhauled" the head, exactly what did you do to the head ? Many guys expect a 235 to spew out oil to the rockers, like a SBC, it just won't happen.
Had similar issue on a 59 motor. After checking the rocker shafts, one was found to be installed with the small flat ground facing up. Both should be facing down. Solved my oiling problem.
Behind the push rod cover is a 1/8" line that moves oil from the rear cam bearing to the top of the block for rocker oiling. It doesn't take much crud to restrict or plug the line. Pull it off, clean it with carb or brake cleaner. Look at the oil p***ages in the upper block where the line connects, and in the head where the connector plugs in - make SURE those p***ages are clean as well. I made a priming tool for $2 - a big screwdriver form Harbor Freight with the handle wacked off, the blade ground to fit the tang on the oil pump. Spin the oil pump until you see oil come out the weep holes on the top of each rocker. It will take a couple minutes, but if everything is clean, you will see the rockers oil. On SOLID lifter engines, I set the valves .003" OVER hot lash specs, puts me within a thou or two. I set 2 valves HOT, then check the same valves stone cold, and adjust the remainder. I mark the distrubutor housing, set each pair of valves at TDC, folowing the firing order. Good Luck, Tim
REMOVE THE ROCKER SHAFT AND BOLTS, REMOVE SPARK , SPIN ENGINE UNTIL YOU SEE THE ENGINE OIL FLOW OUT ONE OF THE ROCKER BOLT HOLES, CAREFULLY INSPECT ROCKER SHAFT BOLTS , ONE IS NARROW SHAFT THAN THE OTHERS. I THINK YOU HAVE THE WRONG BOLT IN THE WRONG HOLE...
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