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FrozenCaveman

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Bah! I thought I had a quick and easy job to replace the control valve on my /6 distributor today. I made the mistake of not marking the rotor, figuring if I was careful, no problem inserting it back in the same place. Dumb.

I'm not real familiar with finding TDC, but I'm fairly certain I have the rotor in the correct spot now after pulling plug #1 and turning the motor by hand to the timing mark (twice). I stuck a piece of vacuum hose in the plug hole and figured out that the second time around I must have been on the exhaust cycle because the hose went in way further than my first visit to the timing mark. So with the rotor pointing at #1 with the 0 degree mark matching up with the notch on the pulley and with my relative certainty at being at TDC, I tightened down the distributor.

The first time through this, I forgot to adjust the magnetic pickup on my Pertronix Ignitor, so after making sure the gap was about .030 again, the engine won't fire.

I thought maybe I flooded the stock carb, so I used the pen in the butterfly trick, but still nothing. Except when I occasionally flood the carb, I never have problems starting this car. It could sit for a year and it always fires up on the first crank.

What's my next step? I'm pretty frustrated with a job that I thought would take less than an hour.

Thanks...

-JP
 
old trick, put a small ball of paper towel in the #1 spark plug hole disconnect coil bump over starter until you hear paper towel pop out. Check and see where your at on timing marks set at 10 degrees or 8 BTDC start your firing order at # 1 pointing at rotor
 
The depth of the piston has nothing to do with compression stroke or 1 turn (of the crank) "off" The piston is up at the TDC mark whether it's the no1 firing stroke or not.

There are two ways to find out, other than guessing

One was posted above, on V8's you can "stick your finger in" and feel for compression. You could also use a compression gauge

The second way "if you happen to have" the valve cover off, is bring the marks to TDC and see if both no1 valves are closed. If not, turn the crank 1 turn

Slants are more complicated because there is very little dist. movement, and the gear moves a bit as you drop it in. I guess you know there is a second bolt up under the dist.
 
67Dart273 said:
The depth of the piston has nothing to do with compression stroke or 1 turn (of the crank) "off" The piston is up at the TDC mark whether it's the no1 firing stroke or not.

There are two ways to find out, other than guessing

One was posted above, on V8's you can "stick your finger in" and feel for compression. You could also use a compression gauge

The second way "if you happen to have" the valve cover off, is bring the marks to TDC and see if both no1 valves are closed. If not, turn the crank 1 turn

Slants are more complicated because there is very little dist. movement, and the gear moves a bit as you drop it in. I guess you know there is a second bolt up under the dist.
Click to expand...

OK, sounds like I need to double check TDC again. The paper towel trick might work better if I had a helper - isn't there a decent chance I'll just crank it past the compression stroke and end up somewhere in the exhaust stroke?

Regarding the 2nd bolt on the underside of the dizzy, what's that for? I haven't adjusted it at all since I've had the car. Does that give me additional rotation beyond just loosening the bolt on the block?

I don't have the valve cover off atm, but with the oil fill hole, I might be able to shine a light in there to see the 2 valves up front. Otherwise I should probably get a compression gauge - will hand cranking the motor slowly be enough to register on a gauge? With the fan on there, I'm only getting maybe 1/8th turn with a breaker bar.

Thanks, guys... I needed a sounding board and someone to set me straight.
 
I went out there with a light and checked on the valves - one was pretty clearly compressed. I bumped it over until I got the timing mark close to zero and checked again on the position of the front valves. Looks like both are at the same height, neither appearing to be compressed - is that what I want for TDC? If so, I'm 180 degrees off, can pull the dizzy, and point it to #1 again.

-JP
 
FrozenCaveman said:
I went out there with a light and checked on the valves - one was pretty clearly compressed. I bumped it over until I got the timing mark close to zero and checked again on the position of the front valves. Looks like both are at the same height, neither appearing to be compressed - is that what I want for TDC? If so, I'm 180 degrees off, can pull the dizzy, and point it to #1 again.

-JP
Click to expand...
Yes, you want both valves to be closed, no pressure from the rockers on the valves
This is top dead center of the compression stroke

You are indeed 180 degrees off...and you might be surprised to see how often this occurs
 
Once I get the approximate timing corrected, I saw another post that mentioned getting the timing dialed in close to zero degrees by turning the key to the run position and twisting the dizzy until I hear a pop from the spark. I've also heard that I can burn out points that way. Is that a safe practice with a pertronix kit? I'd hate to fry my components and be back to square one.

Thanks...
 
Definitely sounds like you were 180* off. I turn my slanty using the fan to get it dead on. No reason to mess with the second adjustment on the underside of the dizzy unless you want to get more advanced with your tune. (Nice pun there) Main thing is to get it running. If you don't have a timing light, check with your local big auto parts store and see if they'll rent you one for free. Most people will say set the timing at 7-10 degrees for a start.

I've never used Pertronix, is that .030 gap correct?
 
KosmicKuda said:
Definitely sounds like you were 180* off. I turn my slanty using the fan to get it dead on. No reason to mess with the second adjustment on the underside of the dizzy unless you want to get more advanced with your tune. (Nice pun there) Main thing is to get it running. If you don't have a timing light, check with your local big auto parts store and see if they'll rent you one for free. Most people will say set the timing at 7-10 degrees for a start.

I've never used Pertronix, is that .030 gap correct?
Click to expand...


That makes sense about the 2nd adjustment... I remember being mystified why I couldn't advance the dizzy more than around 14 degrees. The Pertronix is .030, yes.

After doing a 180 with the dizzy, it's very close to firing - sounds like it wants to. I rotated the dizzy a little bit and not much improvement if any. Could it be off by one tooth? I'll try going one tooth in either direction and see...
 
I had better luck moving it one direction than the other. Got it to fire, but it would immediately die. Tried rotating the dizzy a bit as well in that configuration, but no luck. I'm going to hook up a trickle charger for the time being. Battery can't last all that much longer...
 
There are three players in this game;
The TDC being on the compression stroke, and the magnetic pickup alignment, and the rotor to tower alignment.
#1)So after you have correctly found TDC-compression, relocate the balancer index slot, from TDC to 8 degrees advanced.
#2)Then align the pick up polepiece with a reluctor tooth. Then, pop the coilwire out of the cap and near-ground it.Move the cap out of the way. Turn the key to run being carful NOT to bump the starter. Then grab that " control valve" (which I call the Vcan, short for vacuum advance canister), and back it up about 5 degrees, turning it in the direction that the arm on the control valve is pointing,retard. Then pull it back the way you came. Just before or as the pick-up and reluctor tooth align, a spark should jump from the coilwire to ground. If it doesn't then perhaps you need a bit more speed. If you cannot get a spark, something is wrong. But,once you have the spark, Try to figure out exactly when it sparks in relation to the polepiece to tooth alignment. Set it there and snug the bolt down a bit, just so it stays there, and turn the ignition off.
#3) then put the rotor on, and mark the D-house,on the outside, exactly where the rotor tip points to. Next set the cap on the D-house and index it so its on correctly. Now go look at the mark you made;it should be directly under a tower, and hopefully the tower that sends the spark to the #1 cylinder.Now if that is the way it is, it will start. So secure the cap.
But if the tower wire goes to a different cylinder, you have two choices; namely A) rewire the cap, or B) start over with the rotor reindexed to the correct tower. The engine doesn't care which you do. If you choose to rewire the cap, just put the #1 wire into the marked tower, and move each wire over in sequence, following the firing order, 1-5-3-6-2-4. And I think on a slanty, this is CCW.Check it twice, so you don't have to thru the hassle of finding TDC compression again. After it fires up, you can reset the timing with a light.

But on the off-chance that the mark you made on the D-house, indicating the rotor-tip,does not end up directly under a tower; it doesn't have to. It can be almost up to 1/2 tower space either way off center, and it will still idle. But as you might think, the closer to right under the better. But if it is off, then it is better for it to be one way than the other. Which way? Grab the rotor and twist it. If it moves CCW then the rotor tip could be CW of the tower
 
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Wow, thanks for the details you provided, AJ! I will be able to work on it tomorrow again, so I'll try to follow your instructions - they make sense as I read them.

-JP
 
Success! Got it running, dialed in the timing at around 10 degrees advance with a timing light (vacuum pod and carb plugged). Part of the problem I was having was that the rotor was damaged enough to retard the timing. Timing on the tooth I put the dizzy was about 25 degrees max advance, and that's about 10-11 degrees more than I was able to advance it previously (that's without vacuum advance), so this was a long term issue. I think I've just been overcoming the bad rotor with twisting the dizzy to advance timing. I thought it looked funny, but it didn't click for me that it was bent - for some reason I thought that's the way it came from the factory until I bought a replacement today on the off chance it was part of the problem. Dumb rookie. You learn more from your mistakes, I guess, than successes.

While I had the vacuum line off for timing, I figured I might as well test the vacuum from the (stock) carb - it was only reading 6 Hg at idle, but very steady. Is that enough?

Thanks for all your advice and procedures. They helped immensely - now I've got the timing where it should be, and fixed a separate issue (the rotor) while I was at it.

-JP
 
If your slanty idles at 6",something is wrong. Maybe the gauge is boofed...or maybe it's plumbed wrong.
If the gauge is accurate,in all likelyhood the timing is off, no matter what the marks say.
But of course, you want to verify the marks first......then hunt for a vacuum leak ....And then make sure the valve lash is correct.....And then we check the cam-timing.......
So, common sense first;
Does it start right up, both cold and hot? If yes this would tend to rule out the valve lash. and the cam-timing.
Does it idle nice at 650 rpm, and how about when you put it into gear? If yes, this would tend to rule out cam timing and compression issues as well;and additionally a vacuum leak.
And how well does it take a load, meaning can you drive away briskly without bucking farting or stalling? This would tend to rule out all issues, except bad timing marks.

Ok so, the easy test then would be to start her up and advance the timing some,with the vacuum gauge installed ,plumbed to MANIFOLD VACUUM, not the sparkport. If the rpm goes up, then that's a good thing, continue advancing the timing;forget what the marks say,continue this way until either;A) it stops idling faster, or B)the vacuum rises closer to 18/20, or C)you run out of ability to advance it any further. Now take it for a gentle spin, listening for detonation, while exercising the gas pedal. How is the power level? Better? Then great.How about Detonation? None? Great. How about at 2000rpm and floored? Still no detonation? Supergreat! Go back to the garage.
OK, with no detonation and increased power with the additional timing, we are on the right track. How's it start now? Click,vroom? Or Rrrrrrrurrrurruirrrrr; that's bad. Or starter kick-back;also bad. If you get either of those starting issues or experienced detonation under acceleration, then you are gonna have to put the timing back, and prove the balancer mark is accurate.
And if it is; then you are on the hunt for a vacuum leak.

But,heehee,
if you measured 6* at the sparkport where the "pod" hooks up, well, then, you can ignore everything above in this post,lol.
That port should be dead, zero, no vacuum at all. The fact that you are measuring 6* speaks to the throttle being waaaay too far open, and that speaks to the timing being waaay retarded, or the engine being waaaay lazy. What do you have the idle speed set at?
 
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AJ/FormS said:
If your slanty idle at 6",something is wrong. Maybe the gauge is boofed...
If the gauge is accurate,in all likelyhood the timing is off, no matter what the marks say.
Click to expand...
can the slanty balances slip like the V8 versions?
 
By the way, Where the rotor is pointing has nothing to do with timing unless the spark would jump to the wrong tower,lol. Triggering the coil is controlled by the magnetic pick-up only. Timing that spark is controlled by when the trigger event happens; and that is the job of the advance mechanisms. At the moment the spark is generated, it doesn't care where the rotor is pointing, it just runs up to the tip, and whatever tower is closest gets the Zap!. It's your job to wire the cap so that the correct tower is there at the correct time,lol. And it usually works best if the rotor tip is properly aligned, on the rotor body..
 
The sticker on the fender says to set idle at 750 in neutral. It was running a little fast, at 840, so I turned out the idle screw by about half a turn and it settled around 750. Do you recommend advancing the timing some more until it pings? It has pretty good pick up already, but I could try advancing it some more. I have another 15 degrees of advance before I need to shift more than just the rotation of the dizzy. I based the timing on the mark on the balancer - engine was rebuild about 30-40k miles ago, if that is any indicator that it hasn't shifted too much in that time.

-JP
 
Well before I get myself into trouble, Exactly where did you measure the 6 inches of vacuum? and if it wasn't directly measuring manifold vacuum then I would ask; "what is the manifold vacuum.

But I think you let the cat out of the bag when you said, that it has pretty good pick-up already. So then my answer would be NO. 10* idle-timing is plenty.
So then, since you have a light, check the timing without the Vcan, at 3000 rpm, and again at 3600. It should be between 30 and 36 degrees. You will need a dial-back lite to see this. Or a timing tape. Or search "hillbilly timing tape".
 
LOL re: hillbilly timing tape. My timing light is a dial-back type, so I can check that this evening. But why would my advance be at 30-36 degrees without the vcan? Shouldn't it only advance with the vcan to give me total advance in that range? I guess I'm not understanding its purpose.

The 6 inches of vacuum was tested at idle on the vacuum port from the carb to the distributor (I plugged my gauge into the line to the distributor). Assuming I have an adapter, I'll try to get a reading from the manifold directly...
 
Your vacuum feed to the vcan MAY be the wrong one. There should be 0 vacuum on the timed vacuum port at idle for older engines and carbs.

BUT... some of this depends on year; the later emissions did some odd things with the vacuum timing, and using 'vacuum amplifiers' rather than a direct timed vacuum feed to the vcan. What year car/engine do you have? It is a Dodge Dart Lite or Plymouth Feather Duster? Does it have a hockey puck looking thing up on the valve cover with vacuum lines in and out? And was the engine fully warmed up?
 
It's a 71 Plymouth Scamp with 225 and the double-hockey puck sized thing on the top of the valve cover towards the back. I'd have to admit that the engine was not fully warmed up when I checked the vacuum reading. I ran the engine only long enough to set the timing and check the vacuum.

I think it's manifold vacuum to the distributor, but I'd have to look at it again. There's another blocked off line on the carb that I'm assuming is ported vacuum (higher up on the carb?), but it's the original carb. My mom bought the car new, so I'm fairly in tune (pun intended) with its history.
 
If the puck is about 3" thick with just one vacuum line to it, then it is likely a vacuum canister for the air system, not a vacuum amplifier that was part of the later emissions. I don't think the '71' had the vacuum amplifier. Confirm if there is just one line to this puck thing.....

If you are measuring the manifold vacuum, then 6" HG is not normal at all. Confirm that you gauge is reading INCHES of mercury not something else. If it really is manifold vacuum, and really is 6" at idle, then you have a massive vacuum leak somewhere under the carb or in the intake or in the hoses.

The warmed up or not just has to do with the temp switched vacuum on the later engines.

The ported vacuum (blocked off in your case) is what would go to the vcan on the older engines. It ought to have 0" vacuum at idle. Other car mfrs in that era used manifold vacuum for the vcan; my 70' Ford did IIRC (vacuum retard at idle).

Oh yeah... I see you are in CA.... I get totally lost on the emissions mods for CA.
 
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