Put a new set of heads on my 348, now the valves don't seem to want to adjust properly and I have low compression in the number 4 cylinder. I have 9.5 compression the 921 Showcars Isky 488 lift cam and stock rockers. Put the heads on with new Cometic gaskets along with the other gaskets all new. Set the timing adjusted the valves and as I seasoned the new springs I had clatter. After shutting it off and cool down went back readjusted the valves again. I cranked the engine over a few times checked the pushrods and I could spin almost all of them again. Adjusted again and the same thing. Ran the engine for a bit still had ticking from what sounded like a few rockers on both sides. At this point the engine isn't idling like prior to the head swap its rough and not smoothing out. If I give it a quick hit on the gas it stumbles. The new heads (817's) had what looked like stock replacement springs. This could have be my down fall. This is what I ran initially and the valves wouldnt adjust. I changed out the springs to Showcars 3357 springs (dont know why i didnt do that in the first place). Did everything over and still i adjust the valves probably 4 times running and just turning over the engine and it seems like they loosen up. The pushrods twist so I tighten them down more crank the engine and become loose again. They do seem to be tighter then with the other springs now but a few keep loosening up even with cranking. I marked the rocker nuts and they are not backing off.
So I turn to the compression test. All cylinders appear to be good except number 4. They all have about 135-145 on crank test. Number 4 has 120. Prior to changing out the heads I did a compression test and they were all good. I loosened both rockers on #4 put a little tranny fluid in and got 190 and it held, it also held at 120. Now while i had the heads removed and just prior to installing the new ones I guess I missed the oil rag on the #4 cylinder and it had some very light rust form and I mean really light. A little WD40 and 1500 sand paper i lightly rubbed on it for a few seconds and it was gone so i dont thing that would be the issue.
So did i ruin a cam or lifters with about 10-15 minutes of run time with the unknown springs? Is my rough idle a vacuum/bad seal on a gasket? I thought maybe the #4 cylinder was from killing a cam lobe or lifter, just at a loss right now. Seemed like a pretty simple switch but now looks like I have 2-3 issues going on. I know its a lot but I'm frustrated. Time for a Pabst or 6.
So I turn to the compression test. All cylinders appear to be good except number 4. They all have about 135-145 on crank test. Number 4 has 120. Prior to changing out the heads I did a compression test and they were all good. I loosened both rockers on #4 put a little tranny fluid in and got 190 and it held, it also held at 120. Now while i had the heads removed and just prior to installing the new ones I guess I missed the oil rag on the #4 cylinder and it had some very light rust form and I mean really light. A little WD40 and 1500 sand paper i lightly rubbed on it for a few seconds and it was gone so i dont thing that would be the issue.
So did i ruin a cam or lifters with about 10-15 minutes of run time with the unknown springs? Is my rough idle a vacuum/bad seal on a gasket? I thought maybe the #4 cylinder was from killing a cam lobe or lifter, just at a loss right now. Seemed like a pretty simple switch but now looks like I have 2-3 issues going on. I know its a lot but I'm frustrated. Time for a Pabst or 6.