78 L82 Idle Issue
Thread Starter
Racer
Joined: May 2005
Posts: 335
Likes: 110
From: Canton GA
After making my plug and removing the old hard line (cut in sections since it was trash anyway), I was ready to install then new hard line. There was no room to get it through, so I removed the lower AC condenser support bracket and still seemingly not enough room. I thought I was going to need to drain the coolant and remove the lower coolant line. But after trying some more angles, I got it in. Only to find the line was nowhere close to lining up with the ports. I hand tightened the connection to the carburetor and the lower end was off by an inch and at a wrong angle. Not sure if it was bent wrong or if it got distorted in shipping. After trying to massage it into place, I made it worse.
I'll sort that out with Zip Corvettes. But in the meantime, I have some 6AN lines and fittings on the way. But also picked up some 5/8-18 inverted flare to 3/8 tube fittings and 3/8 fuel line locally. That way I can at least get to getting the carburetor tuned and checking/setting timing.
I'll sort that out with Zip Corvettes. But in the meantime, I have some 6AN lines and fittings on the way. But also picked up some 5/8-18 inverted flare to 3/8 tube fittings and 3/8 fuel line locally. That way I can at least get to getting the carburetor tuned and checking/setting timing.
Thread Starter
Racer
Joined: May 2005
Posts: 335
Likes: 110
From: Canton GA
That is on the plans too.
After browsing the service manual, is the access through the same hatch as the filler port? And from a quick look, it appears so. That is pretty cool to be able to access it so easily. Except for caution needed for the paint.
After browsing the service manual, is the access through the same hatch as the filler port? And from a quick look, it appears so. That is pretty cool to be able to access it so easily. Except for caution needed for the paint.
Racer
Joined: Oct 2018
Posts: 459
Likes: 134
From: England
After making my plug and removing the old hard line (cut in sections since it was trash anyway), I was ready to install then new hard line. There was no room to get it through, so I removed the lower AC condenser support bracket and still seemingly not enough room. I thought I was going to need to drain the coolant and remove the lower coolant line. But after trying some more angles, I got it in. Only to find the line was nowhere close to lining up with the ports. I hand tightened the connection to the carburetor and the lower end was off by an inch and at a wrong angle. Not sure if it was bent wrong or if it got distorted in shipping. After trying to massage it into place, I made it worse.
Thread Starter
Racer
Joined: May 2005
Posts: 335
Likes: 110
From: Canton GA
From what I've heard it's not uncommon to have to bend the pipe to fit. I certainly had to, which meant taking it on and off several times to get it line up properly. You want to make sure you can do up the nut on both ends by hand before tightening them, to get a leak free seal.
Thread Starter
Racer
Joined: May 2005
Posts: 335
Likes: 110
From: Canton GA
Got the rubber line in and secured. Braided AN6 line or the hard line will come next. But was able to continue work. After a bit of cranking, she finally fired up but could not idle below 1600. There was no way to get it to 800 RPM with vacuum advance pulled and capped. However, I would watch the timing marks as the engine died and was able to see that it appeared to be about 7 degrees base timing. I took a gamble and slightly rotated the distributor, hoping for 2 - 3 degrees. With a few more idle screw speed and mixture adjustments, I was able to get it to sit at about 750 RPM fine with vacuum advance pulled and capped. I checked the new base timing and was sitting at 10 degrees. Lucky me.
So now it starts fine cold or warm and will idle at about 800 - 900 RPM just fine. There is a slight hesitation at throttle tip-in. Will work on that later. I am sure there are other adjustments needed. But my first attempt at tuning carburetor/distributor went about as well as could have hoped for.
Now on to the power steering, then the HVAC and then the stereo. Followed by new carpet, steering wheel, etc. Then it will be a good driver, not that I didn't enjoy it this afternoon putting about 50 miles on it on back roads.
So now it starts fine cold or warm and will idle at about 800 - 900 RPM just fine. There is a slight hesitation at throttle tip-in. Will work on that later. I am sure there are other adjustments needed. But my first attempt at tuning carburetor/distributor went about as well as could have hoped for.
Now on to the power steering, then the HVAC and then the stereo. Followed by new carpet, steering wheel, etc. Then it will be a good driver, not that I didn't enjoy it this afternoon putting about 50 miles on it on back roads.
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