Car running not so good.

Just got done with a major brake job and steering. Car ran fine before I started project. Just finished bleeding brakes, took her out for a little spin and under load she pops thru carb and exhaust. I didn't touch anything but brakes and steering, sorry new gasket on carb accelerator pump and carb base gasket.

I only had time to check firing order and plug wires. Will check timing tomorrow and other things. I just don't know what happened. Sounds like timing, but how. The car was just on jack stands for about a month.

Just got done with a major brake job and steering. Car ran fine before I started project. Just finished bleeding brakes, took her out for a little spin and under load she pops thru carb and exhaust. I didn't touch anything but brakes and steering, sorry new gasket on carb accelerator pump and carb base gasket.

I only had time to check firing order and plug wires. Will check timing tomorrow and other things. I just don't know what happened. Sounds like timing, but how. The car was just on jack stands for about a month.

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Can you elaborate on this issue a tad? What do you mean by pops through carb and exhaust?

Backfires, I said pops because it is not like a loud backfire.

Kinda like a "sneeze"? It may be a vacuum leak, did all the hoses get re-installed? Any unused vacuum fittings?

Sounds like maybe you didn't get the accelerator pump installed correctly? and as Jeff said, check all vacuum lines.

What did you do with the steering?

Vacuum lines look correct. After looking closer the accelerator pump gasket does seem to be seeping. I changed the gasket and pump housing. The old housing was warped.

Car starts fine and idles fine, low rpm seems fine, even in park giving it gas no backfire or pop. Go down the road, get on the gas then Bam, backfires and pops.

72HCode-had steering box rebuilt and put on new power steering pump.

Spray starting fluid in short burst around the base gasket of the carb. Sounds like it's leaking vacuum.

Make sure you're getting good squirts, you might have loosened a chunk of gunk that got in the nozzles.

You defiantly have an issue with the accelerator pump

Weeping is bas , but did you change the orange rubber valve, remember to put the spring back in? It should like you are losing your accelerator pump shot when you move the throttle.

Check the linkage also. The accelerator pump should come on when the throttle is touched, no lag.

It sounds like a lean condition. If it has a holley carb, try a stiffer secondary spring.

I had the same issue with my car and this sounds so dumb. I went through firing order, gaskets, timing etc.. It was the PVC line got plugged into the power brake booster port on the carb base. On Hollys they look the same. You can try to swap them or just plug both and drive the car. If it fixes it then find out what port is for the PVC. Usually it is in the front or the back center and the brakes are on the side, but check your model.

I hope this helps.

Took carb off, took off accelerator pump cover put in new gasket, 72HCode no to new orange plunger yes spring back in. Took out pump squirter cleaned and cleaned fuel filter. Rechecked timing 10 degrees, no weeping at accelerator pump. No backfire or pop in carb now, just in exhaust at higher RPM say 4 grand and more. Maybe just me, but sounds just like passenger side exhaust. Not running lean, took out number one plug seemed a little rich.

Plug a little black. Leaned the choke when I had carb off. Like before starts right up, idles fine. Think maybe bad plug on pass side. I changed plugs last year to Autolite platinum AP24. I know should of just stayed with copper. Changed plug wires at same time. This has me going NUTS.:huh:


Oops sorry 72HCode, did adjust accelerator pump and no lag. Comes on with throttle movement right away.

Could check gap on that one plug and see what you have.

Double check exhaust leak.

Could have slight exhaust leak on passenger side.

I got a defective ignition wire once, if you have a spare that fits you could swap it and see if things change.

It sucks when you change a bunch of parts and suddenly have problems then its very hard to track what is causing what.

I personally discovered how critical it is when you set gap on plugs.

Before I just set them loose with the wire gauge to 35 and they would soot up.

This year I took a feeler gauge and I made sure the plug electrode was really sitting parallel when I set gap and I even used a file to get things to sit flat on the feeler. Wasn't expecting much but the car ran better, I pulled plugs after 500 miles and the suckers were clean.

Devil In the details I guess.

Fixed it. Was the plugs, put the old one's back in. They we're hotter than the platinums. Just took it down the road Purred like a Lion. Just for a little more insurance plan on new coil.

Thanks All.