Popping Carb update

[foothilltom 33]

Hey gents, I'm about 2 hours from leaving for vacation, but I couldn't resist putting in a few minutes on the Stang. Here is an update, as unsatisfying as it might be in understanding the root cause. This will be my last post for 9 days or so.

 

After the compression test over the weekend, I decided to replace all the 20 year old plugs since they were already out. Gapped and did that...was extra careful on the plug wires though the firing order was always good.

 

* Plugged the hole I discovered near my PCV with a golf tee

* Fired up the car - popping as before

* Rechecked the Dwell - confirmed 29 degrees - still popping and noted some smoke out the left side exhaust (from the rear, nothing from the right)

* Rechecked the timing - noted a wacky ATC reading and realized the distributor was very loose and had moved at some point from yesterday

* Set the timing to 8B (screw 6B)

* Turned off the car, tightened the distributor

* Restarted the car

 

Now this is where it gets interesting. I revved the throttle to kick it down to an idle (it was idling really fast) and I *swear* I heard a "clank" of some kind. Not super loud, but definitely heard something. And then...the popping stopped completely. I was dubious of course. I let it run for a minute or two at various RPMs...starting it a few times...the popping seems to be gone!

 

I wish I could better describe the sound I heard, but it was a sound and it signaled the end of the popping -- hell it could have been one last pop for all I know but it was more of a clank.

 

Anywho, the engine is now running MUCH better, no popping, but there are definitely some "lifter" like noises going on. A tick-tick-tick sound keeping time with the RPMs. I can live with that for now, but am definitely going to investigate that more fully when I get back as well as adjusting the carb.

 

But the good news: it runs under its own power! Huzzah. I have more work ahead of me, but I think this annoying chapter is now behind me (fingers crossed).

 

Thanks all for the help and thanks in advance for any other suggestions about the "lifter" noises or what may explain all this.

 

Tom

[Pakrat 1,043]

Well at least you can enjoy your vacation now, go have some fun. The tick tick tick could easily be an exhaust leak. Take it for a spin and see if it goes away when you are smoothly cruising and reappears when you give it some gas.

[Fordrevhead 29]

weird... I''ll venture a guess:

A bent push rod (from a previously stuck valve) was causing the popping. It freed up, now the popping is gone, but now you hear a "lifter" noise.

 

But really, I think it all had something to do with a lifter/push rod/rocker/valve somewhere.

[SlimeGold 69 15]

weird... I''ll venture a guess:

A bent push rod (from a previously stuck valve) was causing the popping. It freed up, now the popping is gone, but now you hear a "lifter" noise.

 

But really, I think it all had something to do with a lifter/push rod/rocker/valve somewhere.

 

 

+1. I would be pulling the valve covers off for a look see. Something is up with one of the exaust valves/rockers IMO.

Edited September 29, 2009 by SlimeGold 69

[NJ_Bob 10]

Well at least you can enjoy your vacation now, go have some fun. The tick tick tick could easily be an exhaust leak. Take it for a spin and see if it goes away when you are smoothly cruising and reappears when you give it some gas.

 

I agree with Pak, I'd check the exhaust first...

[Pakrat 1,043]

I think odds are that FRH and Slime are probably right, I just always like to eliminate the easy/obvious stuff first before I go tearing into or replacing things.

[Fordrevhead 29]

hmmm, awaiting a report back on this one.