No oil right side of valvetrain

I have a Merlin II block on a fresh rebuild that is getting no oil to the right side top end. I have the correct priming tool with collar and primed it before I put it in the car and thought I was sure I had oil coming out of both sides but now after it has run 2 times around 2-3 minutes each time it has no oil on the even side. At idle cold it had around 65lbs and went down to 48 after getting warm, it has lucas 30wt break in oil. I have tried to re-prime (36 lbs) while turning the crank with no luck so I removed the engine to inspect the gallery plugs and it has the correct restrictor plugs in the back for a merlin block and the front plugs look fine but 2 have very small holes which I read was to help in oiling the timing gear. I do have an anti-cavitation pump which I read can give you a low pressure at idle but mine seems to be OK, I also removed the pushrods and they did have oil on the end so the lifter was getting oil. I also could blow through all of them and some had oil in the pushrod but none got to the top. Any ideas where I can be losing pressure?
thanks

How well does the part of the dist above the gear fit the hole in the block?? does it have o rings around it??? Is the dist body relieved in that area so oil can pass it?? some old time engines have been built so the dist has to be orientated just rite so oil can flow thru a notch in the base( not necessarily chev)

same block you had .same lifters . same cam . same dist . ? check to make sure the oil restrictor that the is not pluged up . if thats ok check to see if the lifters are going past the oil band . under the back cam bearing there two feed holes that feed lifters one could be plug with junk

same block, same distributor, new PBM lifters and new erson cam. I will check for any blockage in the oil restrictors.
thanks guys

Tried new restrictors and no restrictors and still cannot get oil to the right side. I did blow compressed air through right gallery hole and you can see oil bubbling from the air around the lifters and can feel air coming through the rocker from the pushrod so the passage seems clear. could the gallery itself be cracked allowing it to lose pressure?
thanks

a few years ago on a bbc that we did machine work on---customer put every thing together with lifters and pushrods full of assy lube(twick red stuff) and the reduced oil flow from a resrictor on the dist side wouldn't pump out---removed pushrods and cleaned, then oil flow was good

Jerry, thanks for the info. I am going to remove the intake so I can get a better look at what is going on. I will be removing all pushrods and lifters for inspection to make sure all oil passages are clear. I did use assembly lube but did not go crazy with it.

you can possibly save time just by removing the rear lifter and if flow there the front one also--once you have established flow at both ends you don't need to do the middle----

yep if you pull the back lifter and prime it and No oil then its is junk in the feed for that side of the block and that feed hole is under #5 cam bearing like i said :) or if oil is comming out then it the base circle of the cam and the oil band is dropping under the lifter bore .there can be some off set in the casting so it could happen .try taking that restrictor out and just use a pipe plug and see if that work s could be going in to far and shuting down the oil feed .you can see in to that part of the block and that galley should not be taped in that far to the feed but ???? check it

I am of no help, but will be following this thread. I have a 468 that I just built about a year ago. The valvetrain started to get noisy and I assumed it was just a rocker or two that needed adjustment so I drove it till I had a chance to adjust em. Cranked it up with the valve covers off and discovered no oil flow at idle so I am gonna guess my rockers are trashed now and hopefully the pushrods are not galled up.

The plugs behind my timing covers also have small holes in them to oil the thrust bearing (retro roller cam).

Finally got oil up to the right side, I ended up taking the restrictors out and just using plugs. It took about 15 minutes for the oil to show up while priming it then another 5 minutes or so to feed all the rockers. Put the motor back in the car and started it, checked valve covers and I have oil now for sure. I called world products to see if they had and suggestions and the tech guy was appalled I was using restrictors because he said those blocks don't need them but they sell them? When I take it out for the first time I will keep an eye on the pressure to see if it pumps all the oil to the top. Thanks Jerry and Pat for your recommendations

i have had many of them blocks in the shop over the years i never use restrictors if your running 1/4 mile your drain back should be ok .you have time between rounds you valve springs will live alot longer with out them

I only need my valve springs to last a few seconds!!!!!

Is all the snow gone Pat??