have a listen

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Sounds like an ignition problem to me. I would be inspecting cap and rotor. Might also be a phase problem, where the rotor is between two cap terminals. Has the wiring for the distributor pick-up coil been modified? Is it an HEI module conversion?

How do your cap and rotor look? Is it a stock distributor?

Its a petronix dist. cap and rotor look brand new.

Looks like the cap and rotor are ok at this point.
 
I let it run for a bit then hit the throttle a few times. It came back, but more subtle.

I have my money on something toasted in the valve train. Take the valve cover off. Maybe you'll get lucky and it's a burned up pushrod end or rocker adjuster. Whatever it is, it's getting worse. Inspect everything VERY closely. If you don't find anything, fire the engine up and take note of how much each rocker moves. If you see one that doesn't move like the others, there's your wiped camshaft lobe.....which is what I think now it may be.
 
I have my money on something toasted in the valve train. Take the valve cover off. Maybe you'll get lucky and it's a burned up pushrod end or rocker adjuster. Whatever it is, it's getting worse. Inspect everything VERY closely. If you don't find anything, fire the engine up and take note of how much each rocker moves. If you see one that doesn't move like the others, there's your wiped camshaft lobe.....which is what I think now it may be.

there isn't alot i can think of that would wear that fast... if it was a lobe i would think it would just go... not clear up with a lash and then come back...

(To OP, re-lash and see if one is now loose, dead give away)

were any of the adjusters really easy to turn? maybe it just backed loose...
 
there isn't alot i can think of that would wear that fast... if it was a lobe i would think it would just go... not clear up with a lash and then come back...

(To OP, re-lash and see if one is now loose, dead give away)

were any of the adjusters really easy to turn? maybe it just backed loose...

When a cam lobe goes, it GOES. I have adjusted a rocker, had a tick go away and come back literally in 10 seconds. The cam lobe was being ground down.
 
When a cam lobe goes, it GOES. I have adjusted a rocker, had a tick go away and come back literally in 10 seconds. The cam lobe was being ground down.

due to the edge of the lifter or just because its no longer smooth? in just curious... check your FB BTW
 
due to the edge of the lifter or just because its no longer smooth? in just curious... check your FB BTW

When the wear pattern on lobes and lifters goes away, wear is VERY quick.
 
Maybe the vacuum advance is hooked up to a full vacuum port. Or a bad distributor vacuum advance diaphragm or the little rod that move's the advance. Also at night run it and see if a header tube gets hotter than the others. that would be the cylinder to look at. Just a thought. :)
 
sounds like a fouled plug , { Holley on a slant six syndrome }

umm what? i need to get a new vid here in a little bit... sounds scary at 850rpm...

[ame="http://www.youtube.com/watch?v=cTr5qVwpUzA&feature=plcp"]Burnout 9/11 - YouTube[/ame]
 
there isn't alot i can think of that would wear that fast... if it was a lobe i would think it would just go... not clear up with a lash and then come back...

(To OP, re-lash and see if one is now loose, dead give away)

were any of the adjusters really easy to turn? maybe it just backed loose...
Their was maybe one that was easy to turn. The rest were pretty hard to adjust. I assume the cut in the palm from the 3/8 wrench is a norm for adjusting valve lash.:D

sounds like a fouled plug , { Holley on a slant six syndrome }
New plugs were put in yesterday. The ones I took out looked fine.

Maybe the vacuum advance is hooked up to a full vacuum port. Or a bad distributor vacuum advance diaphragm or the little rod that move's the advance. Also at night run it and see if a header tube gets hotter than the others. that would be the cylinder to look at. Just a thought. :)
I have two vac lines. one from dist to carb. the other from rear of carb to valve cover. Thats it. Idle rises and falls a little too. Like vac keeps shifting.
 
If you have a dial indicator set it on each rocker on set your dial at the highest point (zero) and then slowly hand turn the engine and record each cylinder. ( disconnect the battery)
That will see if you have worn out lobe... If all good then check your valve gap, timing. get a good timing light so you can set your gun to the timing you need.
You don't know the history of the engine you mitt have a burnt, bent valve, I've also seen the cam button come out of the cam and bend several valves.
Check these few things and if not good/ then I would pull the timing chain cover and check all details, chain, gears, loose cam bolt, ect. If that's OK then being that far into it I would pull the head to visual spec all.
Just a rule of thought,,,,,,,,,,,,popping in exhaust is timing,,,,, popping in carb is valves..............trying to help :D
 
Ok. I advanced the timing more. The valve popping stopped. But it still will not stay running in any gear. As soon as I drop it in reverse. Blahhh. Dies..
 
New video. Listen how the motor surges. Note the timing tab. The white mark is how much advanced I am.
[ame="http://www.youtube.com/watch?v=BXVS9yGVthM&feature=g-upl"]Valiant idle 2. - YouTube[/ame]
 
I'm wondering if your float levels are correct. And another possibility is your vacuum is low enough the power valve is opening some at idle, which would only get worse when you put it in gear. Not sure what carb you have? 390, 450, 600. Possibly could have a 10.5" valve? Were you able to read your vacuum with a gauge yet? Some will discount that the PV should not affect the idle circuit, but i have personally seen it be a issue.
 
Its a 390 I'm pretty sure.I havent been able to read my vac yet. Been gone most of the day. You thinking float is too low?
 
Its a 390 I'm pretty sure.I havent been able to read my vac yet. Been gone most of the day. You thinking float is too low?

Yes i am thinking low, mainly because your plugs you removed were clean. That kinda flies in the face of the power valve issue, which would be a rich idle, but i'm just trying to think of things to check without throwing parts at it. Looked in your video that the timing mark was fairly steady so your timing chain shouldn't be too sloppy.
Also, when you rev the engine does it seen to perform ok.
 
Yes i am thinking low, mainly because your plugs you removed were clean. That kinda flies in the face of the power valve issue, which would be a rich idle, but i'm just trying to think of things to check without throwing parts at it. Looked in your video that the timing mark was fairly steady so your timing chain shouldn't be too sloppy.
Also, when you rev the engine does it seen to perform ok.

Yeah. It revs nice and smooth, and comes down and settles the same way.
 
Yeah. It revs nice and smooth, and comes down and settles the same way.
Well, i think i would try to verify the floats are correct first. Pretty easy to do, but if there high by chance, you'll spill a little fuel right over top of your exhaust:smile:.
 
Ok. Raised the front float. Idles much better. But still wont stay running in once put in gear. Turn up timing more?
 
Ok. Raised the front float. Idles much better. But still wont stay running in once put in gear. Turn up timing more?

That's a good idea. I know your off your timing tab now, but you can kinda eyeball another 5 degrees or so and try it. If that really helps try a little bit more. This is just for test purposes but if it keeps getting better there's a possibility your timing ring has spun on the balancer and you've been getting false readings all along?
 
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