Triumph Repair: rocker arms frezing to rocker shaft, triumph spitfire mk3, rocker shaft

Question
I have a '69 Triumph Spitfire Mk3. About a week ago I decided to replace the rockers because they were warn. I found that the shaft was warn as well so I decided to rebuild the whole thing. Started it up and she ran great... great for about 10 miles. The fourth rocker froze and threw the push rod. I found that the locating screw didnt quite fit the rocker shaft correctly and I thought this maybe causing a lack of lubrication. I then rebuilt the rocker assembly using new push rods... but the same rocker posts. She drove really good all day then.... Same thing happened, fourth rocker froze and threw the rod. Before I drove it I ran it with the rocker cover off to check and make sure it was getting lube. Quite a bit of oil was seeping out under the last rocker stand, but all of the rockers seemed to be bubbling out a really small amount of oil. I really thought that I had fixed the problem. I have been working on this car for 2 years and have $6000 into it. I am really down and hope you can help.

Answer
Hi Tom,
I would confirm again the lube holes and since it is getting oil, I would hone out that rocker a little as it sounds like it is either too tight and not lubing well or there is a problem in the oil passage. Also, you didn't tell me how much oil pressure you have. I like to see 25 to 35 at idle with hot oil and 45 to 75 at cruise with hot oil.

What weight oil are you using? I like 10w-30 in cold weather and 20w-40 in the summer. Don't count on any manufacture for correct oil clearance anywhere in the engine.

Howard