Weak valve springs sound likely here. Do you have solid "before" tune up specs? Do you "know" what the timing and engine idle speed
are? A spark plug that is not seated properly can also give weak performance, you might double check that, too...
I think you can improve performance before you plan the rebuild. A couple of things that I preach often over the internet is to replace the stock timing gear set, and examine the balancer! Both can cause very hard to diagnose problems...
are? A spark plug that is not seated properly can also give weak performance, you might double check that, too...
I think you can improve performance before you plan the rebuild. A couple of things that I preach often over the internet is to replace the stock timing gear set, and examine the balancer! Both can cause very hard to diagnose problems...