Help! 78 Vette Engine issue
Racer
Joined: Jul 2013
Posts: 257
Likes: 36
I’d cut my losses and have another shop look at it. Do you have a Corvette club in your area? They can recommend a shop, or better yet have one of the guys take a look.
Hard to tell from the video, but if it’s rod knock you’ll need to pull the motor. I also have a 78, l48 and installed an Edebrock top end kit. I hammered it (as derekderek mentioned) and on the third run spun a rod bearing and ended up pulling the motor.
Good luck on resolving this.
Hard to tell from the video, but if it’s rod knock you’ll need to pull the motor. I also have a 78, l48 and installed an Edebrock top end kit. I hammered it (as derekderek mentioned) and on the third run spun a rod bearing and ended up pulling the motor.
Good luck on resolving this.
Last edited by hpxt; Nov 8, 2017 at 11:43 PM.
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
Seeing this a lot of boats. Guy has it treats it pretty gentle 3500 RPM all the time. New guy buys it. Full Throttle 5,000 RPM. Engine Pops in less than a week. Complains that the guy sold him a boat with a bad engine. You want to drive it like a dragster? You need a new crankshaft in it-good bearings with correct clearances anyway. A tired engine with .005 or more will stay alive as a commuter-grocery-getter.
Last edited by derekderek; Nov 9, 2017 at 06:34 AM.
Thread Starter
Instructor
Joined: Jul 2008
Posts: 167
Likes: 0
That could be associated with running the car while lean?
You might have something there.
Burning Brakes
Joined: May 2013
Posts: 789
Likes: 129
From: Los Banos CA
Yeah, after listening to your video, I wouldn't describe that as a 'popping' sound. It does sound more like something worse. To find a reputable shop in the Temecula area, I would start another thread with something to that effect in the title (not everybody here reads every single thread).
Thread Starter
Instructor
Joined: Jul 2008
Posts: 167
Likes: 0
Yeah, after listening to your video, I wouldn't describe that as a 'popping' sound. It does sound more like something worse. To find a reputable shop in the Temecula area, I would start another thread with something to that effect in the title (not everybody here reads every single thread).
The shop overhauled my carburetor, gave me my car back with it running lean. Drove it back to the shop three times and this is what I get.
Thread Starter
Instructor
Joined: Jul 2008
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UPDATE: I had my insurance send over a master technician to surmise what the hell happened. The tech came to my residence, and started looking at everything he could. He noted the carburetor was not adjusted properly (in fact it was running rich). He als noted the service to the carburetor was not complete and there were some linkage and valve issues... he tugged on the carburetor valve and I was leaking fuel (engine was off).
Furthermore, he hear an issue with the lifter on the engine over valve 6 and/or 7. Did a compression test with an old type of machine and found out the engine is failing the compression test. His diagnosis and the discover of blue and black smoke tends to think the engine is dying on its own due to age.
So... I need a new engine! This was the original 350 small block for my 78 vette and it was just its time. I found it all too convenient that it dies right after a visit from the corvette shop... but there you go.
Furthermore, he hear an issue with the lifter on the engine over valve 6 and/or 7. Did a compression test with an old type of machine and found out the engine is failing the compression test. His diagnosis and the discover of blue and black smoke tends to think the engine is dying on its own due to age.
So... I need a new engine! This was the original 350 small block for my 78 vette and it was just its time. I found it all too convenient that it dies right after a visit from the corvette shop... but there you go.
Thread Starter
Instructor
Joined: Jul 2008
Posts: 167
Likes: 0
My insurance sent over a master tech today and he took a look at the engine. He says it is an issue with the engine due to old age and that it fails the compression test.
Thanks
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Thread Starter
Instructor
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I found out why the vehicle is running rich... it disguises the popping. I believe my Holley carb has a power valve issue. Could this popping sound be the result of a power valve blowout?
I reviewed my invoice of what the insurance paid for repairs, and this shop charged over $600 to overhaul my Holley Carb... that is robbery! Anyway... the engine has issues now because of the can running lean... piston rings damaged and oil leaking through valve guides causing me to blow white smoke. Anyone know of a Corvette Shop in Temecula or what steps I can take to get my money back on this carb?
I reviewed my invoice of what the insurance paid for repairs, and this shop charged over $600 to overhaul my Holley Carb... that is robbery! Anyway... the engine has issues now because of the can running lean... piston rings damaged and oil leaking through valve guides causing me to blow white smoke. Anyone know of a Corvette Shop in Temecula or what steps I can take to get my money back on this carb?
