Profile Picture

Tinny Popping Noise During Tuning

Posted By customline3859 Last Month
You don't have permission to rate!
Author
Message
customline3859
Problem Posted Last Month
View Quick Profile
Supercharged

Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)

Group: Forum Members
Last Active: Last Month
Posts: 37, Visits: 677
Good morning everyone. I hope you guys had a better weekend than I did. I've gotten my rebuilt 304 ci. Y to fire up and run for a brief time. On the initial start up, it ran fairly smoothly, but when it warmed up a bit, the valves began to get a little noisy. We adjusted the valves and in the process of the tuning phase, the engine began to make this loud tinny, popping noise. It won't stay running. I have a pertronix ignitor and flamethrower coil. I started looking through their troubleshooting information, but it basically states that the pertronix is either going to work completely or not at all. They attribute running issues to low voltage. When it began having issues, the battery voltage was low, so I purchased a maintainer/charger to make sure the battery was not an issue. I found 12.45 volts at the coil with the ignition switch off and about 10.5 volts with the key on. I assumed the ignition switch was just drawing the battery down too far, so I replaced the switch. I'm still having the same voltage drop, so I'm assuming that the switch just requires that much voltage. Is that correct? I'm just not sure where to go at this point. I've reached out to the gentleman who put together my 3x2 setup for baseline carb settings. I can't really set the timing until I can keep this thing from popping and carrying on. Any advice or information would be greatly appreciated. I have about a month until we move and I really have to have this thing moving under it's own power. Thanks in advance.

David
Gene Purser
Posted Last Month
View Quick Profile
Supercharged

Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)

Group: Forum Members
Last Active: 15 hours ago
Posts: 204, Visits: 4.9K
That voltage drop is not normal. Check to be sure you have 12v at the ignition terminal on the switch. Then disconnect the coil wire at the coil and check voltage at the disconnected end. If still low, you have a loose connection or faulty wire from the switch to the coil, or maybe a resistance wire has been installed. You can try running a jumper wire from the positive post on the battery to the coil to see if it improves the running. If it does, a new wire is in order. 
customline3859
Posted Last Month
View Quick Profile
Supercharged

Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)

Group: Forum Members
Last Active: Last Month
Posts: 37, Visits: 677
How could I go about finding this resistance wire? It was suggested on another site that there was a ballast wire added that is not needed with the pertronix and coil. 
Gene Purser
Posted Last Month
View Quick Profile
Supercharged

Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)

Group: Forum Members
Last Active: 15 hours ago
Posts: 204, Visits: 4.9K
Check my post for edit. If you have low voltage with the wire disconnected from the coil, replace it. 
Gene Purser
Posted Last Month
View Quick Profile
Supercharged

Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)Supercharged (460 reputation)

Group: Forum Members
Last Active: 15 hours ago
Posts: 204, Visits: 4.9K
I just re-read your post.... 12v volts at the coil with the ignition switch OFF is NOT normal. You might have other problems. Try disconnecting the ignition coil wire and run a separate wire from the battery to the coil. Which Pertronix are you running?
Ted
Posted Last Month
View Quick Profile
Co-Administrator

Co-Administrator (10.0K reputation)Co-Administrator (10.0K reputation)Co-Administrator (10.0K reputation)Co-Administrator (10.0K reputation)Co-Administrator (10.0K reputation)Co-Administrator (10.0K reputation)Co-Administrator (10.0K reputation)Co-Administrator (10.0K reputation)Co-Administrator (10.0K reputation)

Group: Administrators
Last Active: 2 days ago
Posts: 6.3K, Visits: 151.7K
I’ll suggest revisiting the tappet adjustment.  This sounds like a tight intake valve or two.

Lorena, Texas (South of Waco)


customline3859
Posted Last Month
View Quick Profile
Supercharged

Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)

Group: Forum Members
Last Active: Last Month
Posts: 37, Visits: 677
I'm going to start there and work my way out. I've watched The YBlockGuy's adjustment video about 5 times now. 
customline3859
Posted Last Month
View Quick Profile
Supercharged

Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)

Group: Forum Members
Last Active: Last Month
Posts: 37, Visits: 677

So here's what I found when I removed the valve covers. Two broken rockers and 3 bent pushrods. Valves do not seem to be stuck. Rockers were on new shafts with plenty of oil getting to them. Is it possible that the arms just failed from years and years of use?
Florida_Phil
Posted Last Month
View Quick Profile
Supercharged

Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)Supercharged (2.1K reputation)

Group: Forum Members
Last Active: 13 hours ago
Posts: 868, Visits: 194.9K
Yikes!   That's not a tiny popping noise.  You most likely have bent valves and maybe a bad piston or two.  I doubt the rockers broke due to fatigue. Look for the guy with the size 20 shoe...   Crying


http://forums.y-blocksforever.com/uploads/images/82ad85c1-6def-4eb4-a085-3dd2.jpg

customline3859
Posted Last Month
View Quick Profile
Supercharged

Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)Supercharged (103 reputation)

Group: Forum Members
Last Active: Last Month
Posts: 37, Visits: 677
I said it was tinny, not tiny. It's been suggested that due to the vehicle not running for approximately 6 months now that it's possible the aging fuel caused a temporary valve sticking issue, which bent the pushrods. With the pushrods being a hardened chrome moly, could have caused the rocker arm breakage. 


Reading This Topic


Site Meter