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I found this today. Is this why it appears that the orange paint has been painted over with blue? And are there any suggestions for cleaning the oil/dirt build-up under the engine? Found under the crud.
All C3 engines were painted Corporate Blue from the factory starting in very early '77 production thru '81 cars. '82 cars, I believe, had engines painted black from the factory. All C3 engines were painted orange prior to '77. You will need a good degreaser to remove the oil and grease gunk. My engine was a gunk mess when I bought the car, however, my classic car shop cleaned my engine and undercarriage up very nicely, so I don't know which degreaser they used. I have used various degreasers to clean up a multitude of components on my '79.
Originally Posted by MarkW68
Does this additional hole mean I can install a true dual exhaust? Possible dual exhaust?
Yes, two pipes are designed to pass through the two holes in all crossmembers fitted to C3 cars until one-hole crossmembers were first fitted, I believe, for 1980-1982 cars. Chevrolet went to the cat-back exhaust starting in 1975, but they continued to fit all cars with two-hole crossmembers thru 1979 production.
Car is missing the distributor shielding and air cleaner dual ducting, but it looks like the original L82 valve covers are present. Also, you have an in-line fuel filter that needs to go. Not safe. Hopefully you still have the QJet carb.
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1979 L82 M21 FE7
Classic White / Doeskin
Yes, that's the ticket. The factory setup for fuel delivery to the carb is safe and has always functioned well. Let the built-in QJet filter keep the fuel clean, as designed.
Of course, you would want to replace the fuel filter each time you tune up the engine.
Originally Posted by MarkW68
It does have QJet carb.
Excellent! The original QJet is a great carb.
Check the number on the carb to confirm you have the original QJet. 1979 L82 / THM M4MC should be 17059210 (Rochester). If so, you are golden, and don't ever let that carb out of your possession.
Check the number on the carb to confirm you have the original QJet. 1979 L82 / THM M4MC should be 17059210 (Rochester). If so, you are golden, and don't ever let that carb out of your possession.
This is what I found on the carb #17059228. I looked it up and a site mentioned trucks and corvettes.
This is what I found on the carb #17059228. I looked it up and a site mentioned trucks and corvettes.
I stand corrected. You have the correct original carb. I wasn't looking carefully enough at the NCRS Specifications Guide (1968-1982). I apologize for the oversight.
Evidently, Chevrolet fitted two different QJets on L82 THM cars; one for factory A/C, which you have. And one for cars without factory A/C.
So, according to NCRS...
1979 L82 THM w/A/C should be 17059228.
Therefore, you still have the original carb after four decades. Mine does as well. You and I are blessed.
If your intake manifold is original, it is aluminum from the factory. Saves 24 pounds. Another very good unit.
The inline filter has been replaced by a new pump to carb fuel pipe. It seems the old pipe had been cut to add the inline filter using rubber fuel lines and clamps.
With that filter out of the mix, I am trying to find the replacement that goes inside the fuel inlet. What filter goes inside the carburetor? I find 33052 for a part number, but that is the long filter in the pic. I bought the short one to see if I simply didn't notice something. Of course it doesn't fit either. The manual shows the filter, a spring and a gasket but no part numbers. The filter has to be a skinny little thing.
The inline filter has been replaced by a new pump to carb fuel pipe. It seems the old pipe had been cut to add the inline filter using rubber fuel lines and clamps.
With that filter out of the mix, I am trying to find the replacement that goes inside the fuel inlet. What filter goes inside the carburetor? I find 33052 for a part number, but that is the long filter in the pic. I bought the short one to see if I simply didn't notice something. Of course it doesn't fit either. The manual shows the filter, a spring and a gasket but no part numbers. The filter has to be a skinny little thing.
Virtually all C3 vendors have the proper fuel filter. Corvette Central carries it as part #353058, which is listed as the fuel filter for all '76-'81 C3 cars. I purchased that very filter and replaced mine in my '79. This assumes no one has modified your carb inlet. Hopefully, your QJet is totally unmolested.
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1979 L82 M21 FE7
Classic White / Doeskin
Your intake manifold casting number should be either 458520 ('79 early L82) or 14007378 ('79 late L82). I don't know when the change happened during production. Nevertheless, both manifolds are aluminum.
Mine is 14007378 as my car rolled off the line with only one month left in '79 production. I believe your car was assembled in the first seven or so months, based on the power lock switch location on your interior door panel.
-------------------------- 1979 L82 M21 FE7 Classic White / Doeskin
Virtually all C3 vendors have the proper fuel filter. Corvette Central carries it as part #353058, which is listed as the fuel filter for all '76-'81 C3 cars. I purchased that very filter and replaced mine in my '79. This assumes no one has modified your carb inlet. Hopefully, your QJet is totally unmolested.
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1979 L82 M21 FE7
Classic White / Doeskin
I think it has been modified for some reason. That would explain why I'm so confused about the fuel filter. It looks like there is a threaded fitting inside the inlet. I finally noticed there are threads just inside the inlet that would fit the normal, cup shaped fuel line fitting. Is there an alternative location for a fuel filter? The internal fitting. It looks like a smaller threaded insert has been added. The break is from me not noticing a set screw that had been added to the inlet. Gah! More of a plug shape. The hole is where a set screw went.
Wow, that's creative! The outside threads are wrecked, so someone added an inner thread. Is the "gasket" just that ring of goop? I don't see a sealing surface I'd be comfortable with.
It's probably time for a new carb.
That vacuum port plug is suspicious, too. Your nearest FLAPS will sell you a box of vacuum port caps for $5-. No reason to use vacuum hose and a screw.
Email @lars and ask for his fuel line paper. There is a way to safely add a filter to the steel line between your fuel pump and carb. Send him a link to this thread, too, and be ready for some very honest advice.
I absolutely agree with Bikespace. Lars would know if this carb can be saved and exactly how to proceed. Perhaps he will advise you to send the carb to him for a complete restoration. If so, that is exactly what I would do!
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1979 L82 M21 FE7
Classic White / Doeskin
From: At my Bar drinking and wrenching in Lafayette Colorado
That's a helluva' hack job on the carb. Luckily, it appears they did all the damage outside the pressure boundary of the carb, so the carb can be repaired, less the cosmetic damage they did by breaking the casting with that POS set screw and O-ring repair fitting. (You don't have a good photo of the extent of the broken-out damage area, so I can't say for sure) You're lucky you haven't burned the car to the ground with that repair fitting. You don't need an in-line filter - you need to properly repair your carb and and install a good fuel line before you burn your car and house down. If the carb float bowl casting is broken out all the way down to the gasket sealing surface, you have lost the carb and need to replace it.
From: At my Bar drinking and wrenching in Lafayette Colorado
We're going to do a repair on Mark's carb that I think will work. The tricky part is caused by the loss of a significant arc length of the wall in the threaded area:
On the M4M carbs, the threads are outside of the pressure boundary of the fuel system, so we don't need to have a fuel-tight seal on the threads. But the missing section of the wall will make it a little trickier to to get the tooling to machine the inlet perfectly concentric to the centerline. This will require a temporary epoxy reinforcing wall to be created, with a hard backing, while the inlet is re-machined and threaded. This carb is an 800 cfm L82 carb, so we're going to do everything possible to save it... I'll post up the process and results in a new thread in the C3 Tech section once I receive the carb...
Lars
Last weekend I installed the newly refurbished "Tuned by Lars Corvettes & Musclecars" carburetor, dribbled a little gas into it and turned the key. It popped and fired! Today the car was actually hooked up to a fuel source (gas can) and it started! First time in 25 years that engine has run. It seems to run nicely and it easily restarts. I don't want to let it run long because the gas can setup is less than ideal and it doesn't have much coolant.
Next on the docket is to look closer at the gas tank. I'm thinking to clean and maybe treat it with the gas tank sealer products I've seen. I'll also replace any rubber lines I find. At that point I think the fuel system will be done. You can see the plate Lars added to address my careless mistake. Works well.
Last weekend I installed the newly refurbished "Tuned by Lars Corvettes & Musclecars" carburetor, dribbled a little gas into it and turned the key. It popped and fired! Today the car was actually hooked up to a fuel source (gas can) and it started! First time in 25 years that engine has run. It seems to run nicely and it easily restarts. I don't want to let it run long because the gas can setup is less than ideal and it doesn't have much coolant.
Outstanding! Another original QJet saved by Lars.
Originally Posted by MarkW68
Next on the docket is to look closer at the gas tank. I'm thinking to clean and maybe treat it with the gas tank sealer products I've seen. I'll also replace any rubber lines I find. At that point I think the fuel system will be done.
Yes, replace the "S" hose at the fuel pump.
You are making great progress.
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1979 L82 M21 FE7
Classic White / Doeskin
I am referring to the "S" rubber hose that connects the fuel hard line to the inlet of your engine-mounted fuel pump, which is why it needs to remain flexible. There is one of those.
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1979 L82 M21 FE7
Classic White / Doeskin
I am referring to the "S" rubber hose that connects the fuel hard line to the inlet of your engine-mounted fuel pump, which is why it needs to remain flexible. There is one of those.
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1979 L82 M21 FE7
Classic White / Doeskin
Yes, I have that rubber line. It would be about a foot long if straightened. There is a similarly shaped line that runs next to it. I think it's 1/4 inch and it connects to the return. Maybe it doesn't need the molded shape to work properly? I'm referring to the blurry hose in the background. Drill bits make great plugs. Read that on another post.
Last edited by MarkW68; Mar 12, 2024 at 10:15 PM.
Reason: More details
Hard lines run between the tank and the fuel pump. Rubber hoses are located at the gas tank for feed, return and vapor. Rubber hoses are also located at the fuel pump for feed and return. A hard line connects the pump with the carb, which you replaced when you wisely removed the inline fuel filter. Yes, go ahead and replace both rubber hoses at the fuel pump.
I would also check the fuel pump for proper fuel pressure. My pump went out a couple years ago and that conked out the engine. But that's okay cuz it was forty years old. That's why we love these old cars.
I'm enjoying your bringing this car back to life.
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1979 L82 M21 FE7
Classic White / Doeskin
