New Corvette Owner
Thread Starter
Pro
Joined: Apr 2010
Posts: 603
Likes: 249
From: Carson Valley
I found the source of the sparkles and the noise.
The #2 intake lifter had lost its wire plunger retainer. I found the retainer in two pieces laying in the lifter valley after I pulled the manifold.
The plunger was sticking up and both the pushrod ball end and pushrod pocket on the rocker were hammered.
The cam end of the lifter and the cam lobe looked good.
I found CQED on the side of these rockers, does anyone recognize that?
Google doesn't bring anything up and I didn't see it listed as a brand at Summit.
If I can't ID the rockers I'll assume they're chinese junk and round file the lot of them.
The #2 intake lifter had lost its wire plunger retainer. I found the retainer in two pieces laying in the lifter valley after I pulled the manifold.
The plunger was sticking up and both the pushrod ball end and pushrod pocket on the rocker were hammered.
The cam end of the lifter and the cam lobe looked good.
I found CQED on the side of these rockers, does anyone recognize that?
Google doesn't bring anything up and I didn't see it listed as a brand at Summit.
If I can't ID the rockers I'll assume they're chinese junk and round file the lot of them.
Thread Starter
Pro
Joined: Apr 2010
Posts: 603
Likes: 249
From: Carson Valley
I finally got the engine running good and I had a good test drive today.
I spent a week tweaking the timing and repairing the distributor. It ran good in the shop but when there was a load on the engine while driving there was popping in the exhaust on throttle tip in, and very poor acceleration.
After finding one of Lars posts explaining how this is caused by a lean condition I decided to reseal the intake manifold and have a look inside the carb.
The carb (a reman Q-jet off a '76 CA Camaro w. 350) was jetted one step lean so I ordered a set of the proper jets.
While waiting for them to come I was given a couple more Q-jets, one was a match to mine so I opened it up, the power piston spring was taller and a bit stiffer so I used it when I reassembled the carb with the proper jets.
Since the manifold was off it was replaced with an Edelbrock 2101, and I installed new stamped steel rockers. I found a crack in one of the other roller rockers.
I couldn't ID them so figured better safe than sorry and replaced them all.
No more stumble, hesitation or lean popping in the exhaust. It runs good enough that I got it on the highway for a couple good blasts.
Now I can here/feel a rumble from the drivetrain. U-joints are next.
I spent a week tweaking the timing and repairing the distributor. It ran good in the shop but when there was a load on the engine while driving there was popping in the exhaust on throttle tip in, and very poor acceleration.
After finding one of Lars posts explaining how this is caused by a lean condition I decided to reseal the intake manifold and have a look inside the carb.
The carb (a reman Q-jet off a '76 CA Camaro w. 350) was jetted one step lean so I ordered a set of the proper jets.
While waiting for them to come I was given a couple more Q-jets, one was a match to mine so I opened it up, the power piston spring was taller and a bit stiffer so I used it when I reassembled the carb with the proper jets.
Since the manifold was off it was replaced with an Edelbrock 2101, and I installed new stamped steel rockers. I found a crack in one of the other roller rockers.
I couldn't ID them so figured better safe than sorry and replaced them all.
No more stumble, hesitation or lean popping in the exhaust. It runs good enough that I got it on the highway for a couple good blasts.
Now I can here/feel a rumble from the drivetrain. U-joints are next.
Melting Slicks
Joined: Aug 2016
Posts: 2,347
Likes: 1,179
From: CLEVELAND STUCK IN OHIO
2024 C3 of the Year Finalist- Modified
Are your new tires on yet?
Motor mounts?
Trans mount?
I had the harmonic balancer come apart on a '75, thought it was drive train noise,,🤷 fortunately found that befor things went really bad,,
Motor mounts?
Trans mount?
I had the harmonic balancer come apart on a '75, thought it was drive train noise,,🤷 fortunately found that befor things went really bad,,
Thread Starter
Pro
Joined: Apr 2010
Posts: 603
Likes: 249
From: Carson Valley
Tires are on, I noticed the vibration with the old tires and had hoped that would be it.
I spent a long time hunting a similar noise in my Dodge pickup, turned out to be the differential bearings. I rebuilt the differential over the winter.
If this one needs rebuilt it will be no big deal but I hope it's something easier and less expensive.
I'll give the mounts a good look, thanks for the suggestion.
The balancer seems good, I can time the engine by it.
I have thought about replacing it when I have the front of the engine apart to install a new timing chain.
I spent a long time hunting a similar noise in my Dodge pickup, turned out to be the differential bearings. I rebuilt the differential over the winter.
If this one needs rebuilt it will be no big deal but I hope it's something easier and less expensive.
I'll give the mounts a good look, thanks for the suggestion.
The balancer seems good, I can time the engine by it.
I have thought about replacing it when I have the front of the engine apart to install a new timing chain.
Thread Starter
Pro
Joined: Apr 2010
Posts: 603
Likes: 249
From: Carson Valley
I've pulled the aftermarket overflow tank that was miss-installed on the left side, I'd like to see what the left side should look like without it there.
Le Mans Master
Joined: Jan 2007
Posts: 8,012
Likes: 3,343
From: Omaha NE
2025 c3 ('74-'82) of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
2022 C3 of the Year Finalist - Unmodified
2020 C3 of the Year Finalist - Unmodified
These are all I have right now...
