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1971BB427 08-19-2014 10:30 AM

A poor ground will show at the spark plugs. If you pull a plug wire and crank the engine, you should see a good hot blue spark. If it's looks weak, or more white, it may be a poor ground.
Having to keep the pedal to the floor to get it to fire still tells me there's a air/fuel problem.

Camaro 69 08-19-2014 12:17 PM

Valve lash adjustment out of whack perhaps.

78 on my plate 08-19-2014 01:05 PM

On my way out now to quadruple check everything. Valve lash was set the correct way originally but I'm checking again. When it ran last week everything sounded great, no rocker noise at all. I realize that's not enough to go by which is why I'm checking again. Going to check TDC from #1 rockers and start from there on the timing this time. Pulling all the ground straps, getting rid of any remaining paint underneath them and reattaching. I'll check the spark like Vall suggested also. I have a chrome fuel filter right after the pump that I'm going to open up and check for any fuel line shavings also. I know fuel is getting to the carb fine but I saw some black stuff in the carb when I took it apart so it can't hurt to check it. Pulling the plugs to clean off and double check gap on them. I read .050-.060" for engines up to 10.5-1 compression. Does this seem excessive to anyone? I set mine right at .050 when I installed them. I thought I was overly thorough with everything when I did it the first time but obviously there's something keeping the Camaro from running and it's high time it got figured out. Crossing fingers, saying prayers, covering yourself in peanut butter and dancing naked - whatever! Please everyone, channel that good juju into my garage today!!!!

1971BB427 08-19-2014 06:18 PM


Originally Posted by Camaro 69 (Post 693951)
Valve lash adjustment out of whack perhaps.

Very good point! Almost forgot about lash adjustment! And too tight will still start, and not make any noise, if they're too tight.

1971BB427 08-19-2014 06:52 PM

Yes, .050" seems pretty wide for plug gap! Even if you had a MSD box, but especially if you're starting the car without the box. I run mine at .035" even with my MSD boxes on both cars. Tried .045", and it didn't run as well.

78 on my plate 08-19-2014 08:56 PM

3 Attachment(s)
OK, ground straps triple checked, valve lash checked and was fine but reset anyway. Got some serious fuel down in the heads, it soaked a piece of paper towel that I set in the #1 plug hole to know when on the compression stroke. Good spark, but plugs were soaking wet with fuel. I have now discovered (didn't do it at first when I reinstalled it) that the choke linkage on both sides of the carb are leaking fuel. Not pouring out of there but coming out nonetheless. I have no idea how to go about trying to seal that up? NOTHING discusses that part of the linkage and it runs through the carb body. Couple pics showing where it's leaking. Coming out of the area where the idle speed screw is, the linkage further back also and on the other side where the choke linkage runs into the actual choke body. That's a problem. Fuel pressure gauge is already filling back up with gas also. Doubt there's any way to stop that from happening? New gauge in order? If I had the money right now I'd just be buying a new carb, but I don't, and this one is pretty much new as it is. Any insight/wisdom about how to remedy the leaking linkage? Whether or not that's the problem keeping it from running, it's got to be fixed immediately, if it is fixable.

78 on my plate 08-19-2014 09:08 PM

Forgot to mention Vall, I did install the ignition box and that's where I got the plug gap info. It says it in the MSD manual that it should be .050-.060 on engines up to 10.5:1 compression. I'm going to take the gap down before reinstalling them anyway though.

1971BB427 08-20-2014 08:13 AM

Yes, MSD recommends wide gaps, but it didn't work for either of my cars. The 464 Chev is around 10:1, and the 355 Chev is 10.25:1 and both run .035" gap.

The leakage around the shaft is from huge amounts of gas drenching the plate and running out the shaft. They don't need a tight seal, IF the carburetor is working properly, and not washing down the engine with fuel! You've still got a carb issue, as there are numerous indications that it's flooding badly. Get a new gauge so you know where the fuel pressure is first. Once you know it's down around 5 psi, then you can see if that's the carb issue, or if the carb itself is the problem.

Sudstoy 08-20-2014 03:03 PM

One thing I would do is keep an eye on your oil. My car was flooding out at the start and I flooded the crankcase with gas. You may already be in need of an oil change.

78 on my plate 08-20-2014 10:24 PM

I did already change the oil, but thank you for the advice Sudstoy. We discussed that a page or so back and I could smell gas in my oil when I removed the valve covers. Didn't even try to start the Camaro today but I put some Mobil 1 5w30 synthetic that I had in the garage yesterday. Not the oil that I would want to use in it but it's gotta be better than 93 octane I'm sure. Have to wait a couple days to get the oil from Summit. Working on the exhaust a little bit, trying to find some good spots for a couple hangers. Need to get the exhaust done and get the fenders/nose put back on there. All that would've been done already if I had gotten this thing to run. Still have to get the bracket made for the passenger seat also, almost forgot about that. Just took a day to do something that hopefully won't end up causing a couple weeks worth of problems and delays.


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