Help Needed

[STS05lg]

I have a problem. I changed the oil and filter on my 76 ELC and when I started the car it started to knock slightly. After checking the oil level and using a gage to check the idle oil pressure (*/-20), the knock did  not go away and only got worse. Pulled the valve cover and two of the eight rocker arms are only moving slightly. Checked the two push rods for the rockers that are only moving a little bit and they do not appear bent (they turn freely in place). The prime has not been lost off the oil pump, rockers are getting oil.
Question, any idea what has occurred? Motor is in the car. Mileage today: 25236, oil changed every 3000 miles or less sense new. Previous owner started using Synthetic Oil in 1999 when the car only had 13450 miles oil has been changed every year or 3000 miles sense then, same brand and weigh used 10-30.

G’Day Bruce, you are an expert on these 500s, any assistance would really be appreciated.

Thanks,
Lynn

[James Landi]

You may have a couple of stuck valve lifters-- not uncommon after an oil change when hydraulic lifters collapse for lack of oil and one or two get stuck without a cushion of oil.  I suggest that you take your car for a nice run, say ten or so miles and allow nature to take its course.  Don't rev it... just drive it with the radio on, so you don;t hear the noise.   You may wish to mix some Marvel Mystery oil in the crank case, but with the synthetic oil, I'm not sure it would have the desired effect.  Be patience and have faith... the noise will go away.    Happy day,  James

[V63]

I learned to fill the new oil filter with oil...eliminates that issue.

I agree...let the run a while and it should pump up after a few minutes.

[STS05lg]

Thanks for the reply.

[James Landi]

Lynn,
As long as you have decent oil pressure and you're not revving it in an attempt to "cure" the hung lifters, they should work out and slowly "pump" up over time. If the problem persists, and by that I mean several weeks of driving, and the noise is not diminishing, I would urge you to post the problem again to see if anyone else comes up with a remedy.  I hope, with patience, that all works out for you without having to dig into the valve train.   James

[76eldo]

These engines need zinc in the oil to protect the lifter to cam surfaces.
I only use Lucas hot rod oil in my cars because it's made with the ZZDP in the oil composition. I don't use additives. 10/30 synth is probably a bit thin for this engine.  I'd try another oil change with 10/40 Dino oil and a can of Rislone. It will free up stuck lifters.
Then change it again and use the Lucas.

Brian