I bought a 70 Riviera with the 455 and it had sat for 10 years. The guy had to show me it would run, before I bought it. It has the tap, tap , tap noise. I've ran it and drained the oil a couple of times and put the recommended amount of Sea Foam in and it still does it. I haven't driven it 100 miles yet. I had a 68 impala 327 do the same and it broke loose one day while I was getting on an on ramp and it smoothed out. Do you think this 455 will? Also, I haven't taken the valve cover off. Are the valves set up like the Chevys with the stud and rocker arm on each? Thanks for any comments.
Actually Wayne, the Buick engine family uses rockers mounted on a common shaft rather than the individual stud/ball/rocker arrangement of the small block Chevy. Have you checked the plugs yet? If one is not firing at all, it will be black and wet, smelling of gasoline. How about wires and the rest of the tune-up? If all the parts are good, then it would be time to look into mechanical problems. What are the chances your problem is a stuck lifter? Possible. If it was mine, and I have access to compressed air, I'd see if it is leaking out the intake or the exhaust. A compression test to find a weak cylinder would be next up. Maybe pulling a valve cover on the side with the weak cylinder to see if something is actually stuck open. If so, *lightly* tapping with a hammer on the valve may loosen things enough to get it to snap back closed. You probably don't want it to get stuck any further open that it might already be. Having valves and pistons try to occupy the same space at the same time normally leads to bad stuff happening. :shock: :laugh: I have to ask, why was it parked for so long? Did it start this and somebody decided to let it sit?
Thanks for your reply. The reason it had sat so long was she,the original owner, had it painted ten years ago and then decided not to drive it much. When we still got state safety inspections she said she took into town to get it inspected. So she probably last drove it in 2002, the last year of the inspections and that was on the windshield. The oil was really nasty looking. I hadn't tried looking at it under the valve cover yet. When I have some time I will take a look and see if I can tell what's really going on. I did change the plugs and wires when I got it home. It had a dead miss on the same side due to a plug boot burned in two and the new wires solved that. That one plug looked wet, not oily. I guess it could be the same cylinder. And the engine doesn't smoke. So, I'm hoping for the best.ray: I guess I'll see how the rockers work then. And I appreciate your thoughts.
I had a similar problem one - but it was a collapsed lifter. I had to replace it. The piston was in sideways - there was no way it was going to start working again.
By the way, I'll let you know know what the problem is when I find it. I was just thinking, I wonder if some gunk stopped up a hole in the push rod or somewhere along the line? :idea2:
A broken lifter like that won't be good. I suppose removing the intake and head would be in order if that is what's wrong. Time will tell. Thanks
Here's what I'd try doing. Remove both covers, start her up and let her idle. While idling, give each rocker arm a whack or two with a hammer ON THE END THAT ATTACHES TO THE PUSHROD. If by some chance some goo is jamming the check valve open inside the lifter, this should help dislodge it. Another thing you could try doing is to add 1 qt. of tranny fluid to your oil and drive it around for a while and see if that helps. If she's really rapping though, driving around like that is not the best idea, especially if one of your valves is sticking open. ou:
I took the valve cover off and found the third rocker from the back on the driver side was loose. I tried the tapping with a hammer just to see but when I push down on the push rod and turn it, it feels rough. Tapping on the valve spring side moves the valve. So I'm pretty sure I have a bad lifter for whatever reason it went bad. The others feel snug and smooth when I rotate them with my fingers. So here's my plan. Take the manifold off and replace just that one and a push rod. I don't think the others need anything since that's my only noisy one. Any suggestions or does that sound like a good plan? And does anyone have a good used push rod and lifter for a 70 Riviera 455 I could buy? Thanks. Everyone has been a big help. Wayne
Definitely go with new parts. Installing a used lifter is a real bad idea, it could screw up your cam. I doubt if one new lifter and push rod would cost more than about $15 or so anyway.
Unless you are sure the engine has never been rebuilt you might consider measuring the push rod length. For rebuilds non stock lenghts could have been used.
I found after I made the last post that I can buy a new lifter and push rod rather inexpensively. I should be able to do the job in the week or so. Thanks for the help.
