Seems to be happening alot lately without responses. Us dudes who are usually here quick on the spot have been very busy this summer and not spending as much time online and not even having time to work on our own junk. We need to get better with responses.
Did the vac test help you at all with a diagnosis?
So what was your question Shane? There are tons of things that can cause an engine miss. Even a carb adjustment can cause an engine miss where many guys thinks that's not true. It damn sure can. There is such thing called a Lean Misfire. You get to lean, it can misfire. Bad plug wire, fouled plug, retarded timing, etc are the easy ones. Some reasons are a bit harder to fix and just have to be lived with unless you want to spend the money, like a slightly burnt valve or dirty valve seat.
I totally get the busy part.
I have been too, and only getting on here while I'm at work leaves me not responding to you guys as often or as quickly as I should.
The vac test told me I either have dilluted oil or bad rings, or retarded valve timing. The oil has about 30 minutes on it, but since it is past the break-in, I will go ahead and change it and add zinc again. The engine is low mileage considering it's 33 years old, but the rings could be bad nonetheless. Just doesn't seem right when it ran fine before I pulled the engine to reseal it.
The vac gauge held steady at 15 on idle, but the rpm's were very low. I adjusted the idle up a little and the gauge rose to a steady 16. With the vac gauge holding steady it tells me the carb is adjusted well enough to run it.
The ticking sound has me worried so I didn't run it for more than a couple minutes. The sound appears to be coming from the from right front rockers. The exhaust bolts are all tight so it's not the exhaust leaking. It has a "tinny metal sound" to it anyhow, not an "air passing through a small hole" sound. To me, that means one of the rockers went south already. I suspected a spring broke or went bad, but the heads have about 100 hours on them if that, and the vac gauge didn't indicate weak springs.
So now I am going to pull the spark plugs and check them against the recent pics I have of them. Then pull the valve covers, check the rockers, pushrods, springs, and studs to see if maybe a stud pulled out of the head, and redo the valve adjustment. When I replaced the rockers before, the rotor pointed between #1 and #8 on the cap when #1tdc was on the 0 mark on the timing tab. So I put it back that way after I replaced the cam and timing set. Thing is, there was a ton of slack in the old chain, and this new chain is tight. I will also pull the distributor and get the rotor pointing at #1 instead of tooth off on the cam gear. Very frustrated right now, but will...
