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Discussion Starter #1
Hello. I'm at the end of a 4-month rebuild process and it's go time. I'm as nervous as I am excited. I primed the oil yesterday with my priming shaft and a hand drill but I wasn't satisfied with the results. I didn't get oil up to the rockers so I kept priming until the drill started smoking, maybe 10 min. At that point I saw a slight seep at some of the rockers.
After sleeping on it I decided that since I saw the slight seeping I should go ahead and start it to see if the running it would get oil up the rockers. It started right up and sounded great. No lifter noises and no engine knock noises. It ran smooth with 65 psi oil pressure. While keeping the RPM up to break in my new cam, I pulled the valve cover and saw I still had no oil at the rockers. It ran for maybe a little more than 1 minute.
Any advice on how to proceed? I'd rather be cautious now than sorry later.
The oil is 30W. Could the thicker oil just take more time to get to the rockers? How long can I go without seeing oil up top?
Please comment.

Thanks,
Evan
 

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What are the details of your build? Which lifters? etc... Did you do the work yourself? Any chance that the infamous "hidden" oil gallery plug got left out?

Bear
 

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The rear oil gallery plug has been assembled and painstakingly verified. The rear oil gallery plug has been drilled 0.030" as commonly practiced. I did not thread the front gallery plugs but I staked the standard plugs and used Aviator sealant.
The build was a junk yard 455 from a 73 Grandville. Bored .030" over. I had the machine shop clean, bore, polish the crank and install new cam bearings. I visually inspected the cam bearings to insure the oil holes had been aligned.
The heads were #96 from a 71 Grand Prix. I had the machine shop clean and disassemble the heads. I took them home for a bench-top port job before returning them for assembly with all new parts. Valves, guides, springs, roller rockers, pushrods, retainers and seals.
I did the engine assembly here using new forged pistons and rods. I used a Comp Cams XE268/lifter kit with a new Melling timing chain. The oil pump is a new standard Melling pump. I took apart the oil filter housing check valve, cleaned and re-installed it.
 

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You should have oil right away. 30W should be OK, I don't see why not. This is a hard call not knowing anything about your engine build, but you can check a few things. x2 with BearGFR if the oil plug has been left out at the rear of the block. It's hidden within the freeze plug at the back of the block.

Possibly the wrong lifters. Many times you are given Chevy lifters which are not correct even though some of the parts books will say they work. The oil groove is not correct and the oil may not be flowing as it should. Check this comparison out: http://www.jbp-pontiac.com/techDoc/PontLifters.pdf

Is it one side not getting oil or both? There are 2 oil galley plugs in the front of the block near the timing gear. If inserted to deep, they can cut off oil supply. Typically when these are replaced, they get tapped, threaded, and screw-in plugs inserted - but not too deep.

If the rocker arms are too tight this can cut oil supply off to the rockers. The lifters spin on the cam lobe and you should typically see the pushrod spinning as well when the engine is running. Although this is for poly locks and not the stock Pontiac rocker arm nuts which get torqued down, you can adjust them as instructed by spinning them with your fingers. This will get you where you should be without torquing the rocker arm nuts down. Then, see how much more is needed to torque the nuts. If you are right on the money, the pushrods should still spin as you torque the nut, then you are good. If you have to tighten them up beyond that, then it may be too much and the pushrod will not spin and you could be cutting off the oil supply in the lifter. Read this: Pontiac Rocker Arm Adjustment

Seeing you have 65 lbs of oil pressure, it may be the wrong lifters. I would not think you would have good oil pressure if the oil galley plug were left out near the distributor - but never had that experience so cannot say for sure.

In any case, you want to address this sooner than later or risk damage to your engine.
 

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Discussion Starter #6
Bear, The lifters are hydraulic.

Pontiac Jim, Both sides are the same. I did get a tiny bit of oil seeping at a few of the rockers when I primed. At one point when priming I got one small squirt at the very last pushrod (cyl 8) which would probably mean the gallery had pressure.
Maybe I should try backing off the rockers 1/2 turn and try priming again. It does have poly-locks. When I assembled, I tightened them until the pushrods started resisting the spin then 1/2 turn more. Maybe my interpretation of spinning resistance isn't accurate and I over-tightened.
If no change I may need to pull the lifters to check them. I bought them from Butler Performance as a kit so I kinda doubt they sent me Chevy lifters. I think I remember checking them against the same info you posted.
I probably need to check the front oil plugs since they aren't threaded. If I understand correctly, if they were in too deep and restricting flow it would only affect the passenger side. I wonder if I could check the front plugs without pulling the timing cover. I think if I pull the harmomic balancer I would see oil pouring down near the seal if the front plugs loosened.
Thanks for the suggestions.
 

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I would think your lifters are OK if you got them from Butler, so rules that out. If both side are the same, little oil, then your front plugs are probably OK.

You mentioned you do have the poly locks. 1/2 turn may be too much. I have always gone 1/4 turn after the lifter clicking stops to "zero lash" the lifters with the engine running rather than adjust them when the engine is at rest. If you compress the valve in the lifter too much, it will cut oil supply. I would back the poly locks off the 1/2 turn to begin with and then use the drill to see if you can get oil flowing. You really need a 1/2 drill motor as a smaller 3/8" drill motor is a bit light to spin the oil pump/oil. But, if its all you have, then give it another try just to see if the rockers get oil. Remember that the drill motor has to be in reverse as the Pontiac distributor runs counter clockwise.

Just for fun, you might want to put an oil pressure gauge at the top of the engine next to the distributor. There is an oil galley plug there that can be removed (if you can get it out easily) and the oil pressure gauge installed in its place. This will give you a reading at the main oil supply that goes to the lifters. If you have 65 PSI or slightly less, then you know it is not the oil supply going to the lifters. If you do this, just make sure you have the correct fittings to tap in the oil pressure gauge at this oil feed.
 

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Discussion Starter #8
I like your idea of setting the valve lash with the engine running but I need to keep the RPM up to 2500 for cam break-in. Can I adjust the rockers at RPM?
I found some time today and tried a few things. I loosened the #8 exh rocker (last in line) about 1/2 turn and still didn't get flow when priming.
I tried the #5 exh and got the same result. I pulled the pushrod out and ran the drill again. With my reading glasses, flashlight and sun just right I could see the top of the lifter. I ran the drill and could see a slight flow of oil at the top of the lifter. It didn't look like enough to pressurize the pushrod.
I pulled the fuel pump for access to the inside of the timing cover. I inserted a metal rod across the front of the block and ran the primer. There was no trace of oil at all on the inserted rod. This rules out the front plugs.
I crawled in the engine compartment and looked down the dist hole while priming and saw a stream of oil from the drilled hidden plug towards the dist gear. I know there is at least some pressure at the end of the oil to the end of the oil gallery.
I know this is a common practice to use the drilled hidden plug but what if it's reducing the pressure enough that it doesn't reach the rockers as quickly as I expect? Or takes longer to build pressure?
I had forgotten about the top plug you mentioned. It would definitely be good to get an actual PSI reading there since that's what the lifters would see.
I'll probably loose a little sleep again tonight.
 

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For roller lifters, that rule about "2500 rpm cam break-in" is not critical like it is for a flat tappet cam so don't worry about that too much. It's more important at this point to get your oiling problem sorted out. What size hole did you drill into that hidden plug?

Bear
 

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Discussion Starter #10
Actually, it is a flat tappet cam so break-in does apply here.
The hole in the hidden plug is 0.030" diameter. I bought it that way from Butler. It's the same size as my book recommends.
I have an extra guage here so I think my next step is to check pressure at the top plug as PontiacJim suggested. That is the beginning of the lifter gallery. If I have full pressure there I will have it narrowed down to lifters or maybe adjustment if I'm lucky. If not, I must be loosing pressure somewhere else.
 

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Discussion Starter #11
OK. I have plenty of oil pressure at the top plug (oil gallery start). And, since I have oil coming out the hidden plug (oil gallery end) I can be pretty sure there is pressure to all the lifters.
I pulled the top plug near the distributor to hook up the pressure guage. I went ahead and took the pressure guage off and got a 30W shower when I tried to prime it again. Oh it pumps all right! I recommend putting the plug back in first.
I guess it's time to pull the valley cover and see what's up with the lifters. It's gonna have to wait cause my son's Ford's transmission took a dump. I'll keep posting when I get back on it.
 

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Discussion Starter #12
As it turns out, I just didn't wait long enough to get oil to the top. I had to wait for 2-3 minutes before the oil started showing up. I'm not sure why it took so long. One theory is that I put assembly lube on both ends of my pushrods when I installed them, maybe slowing the oil. I probably should have only applied it to the top of the pushrods. It sure seemed like a long time but it finally came out so I could finish the cam break in. Thanks to everybody for helping.
 
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