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Static Timing Questions  Rating:  Rating
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 Posted: 01-18-2015 08:54 pm
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mcguan.2
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I moved this topic from the carburetor section because, based on y'all's advice, I've been tackling ground and timing before moving into carburetors. 11609 sat for a month and was driving fine prior, but when I brought the car out of slumber, I had trouble starting it and when I did get her started, the accleration curve was very poor. A lot of spurts and stutters, and the harder I accelerate the harder she struggles, until she's wide open. At that point she responds "normally".

In any case, I've been checking grounds and I'm now able to get it started somewhat easily, though not as easily as I used to be. On your advice, I checked the static timing today and it's at about 29 degrees BTDC! I've been reading here that a 2.0l with Dellortos should be more like 12 degrees. So I'm now wondering two things.

1. I'm pretty sure the PO rotated the distributor to switch from Strombergs to Dellortos. What way should the distributor (or more importantly the knurled nut) be facing? My knurled nut faces almost straight down towards the ground.

2. If I have to make a large degree change in the static timing, like it would appear is the case here, is rotating the knurled nut enough? Or do I need to rotate the whole distributor cap? And is that how this distributor works? It would appear not, since it has the clips on the side. That said, what's my best option for getting from 29 degrees to 12? And any pointers for reaching and turning the knurled nut? It's tight quarters down there and hot, to boot.

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 Posted: 01-19-2015 12:54 am
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mcguan.2
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I found one of Mark Rosenblum's old posts regarding removing the distributor and setting a rough static timing, but there are a couple things I don't understand. He mentioned connecting "a voltmeter or test lamp from the (-) side of the coil to chassis". I don't exactly understand this. Where do I connect the negative probe of the meter? And is the positive probe supposed to go to the chassis?

Also, he mentions loosening the "clamp bolt" so the distributor can rotate. I'm assuming this is the bolt that has a square nut at the bottom and tightens from both ends. This nut was fairly loose when I went to tighten it, which might explain why the timing was so off in the first place, but even when I tighten it all the way I'm still able to rotate the distributor fairly easily by hand. Am I tightening the wrong bolt?

In any case, now I'm unable to get the car started at all, so I don't know where to go from here.

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 Posted: 01-19-2015 01:14 pm
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Brett Gibson JH5 20497
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Sounds like the distributor has pop out of it's drive, there is one nut on a stud from the block that holds the dizzy clamp which holds the dizzy, the clamp around the dizzy has the square nut and when not setting the timing that should be snug enough not to let the dizzy move, from what you have written I would think your timing has moved and that's why you got the 29 degrees.

So put the crank timing mark on TDC and have the cam timing marks line up, (hopefully 110 to 110). pop the #1 spark plug (#1 is the cylinder closest to the radiator) and just make doubly sure the piston is at the top, look on your dizzy cap to see which spark plug wire is going to the #1 cyl. remove the cap and look to see if the rotor is point to that position. Probably isn't, take hold of the rotor and see if you can turn it, you should not be able to if you can the the dizzy has moved to far out and is not seated in it's drive gear, loosen the clamp with the rotor pointing to #1 push and wiggle the dizzy back in so it is seated once again the snug the clamp up a bit to hold it there.

Put it all back together start it up and set the timing around 12 making sure when you loosen the dizzy to turn it you also hold it in, as for the knurled nob that is for strictly fine tuning not course adjustments.

Hope this helps. Brett

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 Posted: 01-21-2015 05:19 pm
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Esprit2
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Does the distributor still have the original breaker points, or has an electronic ignition system (like Pertronix) been installed? Just considering other things that might prevent the engine from starting.

Do the plugs at least spark? There's no point pursuing correct timing if there's no spark. Remove a plug from the engine, replace it's plug wire, and hold the metal body against the engine, or similar good ground. Have a helper crank the engine over while you observe the gap. Does a spark jump? If no, you have more work to do before timing the ignition. If yes, good, let's move on.
mcguan.2 wrote:
(Snip)... I checked the static timing today and it's at about 29 degrees BTDC! I've been reading here that a 2.0l with Dellortos should be more like 12 degrees. So I'm now wondering two things.You report checking the static timing here, yet below you ask how to set the timing. So, how much do you know how to do? If you don't know how to set the timing, should we trust your measurement of the static timing?

29 BTDC is way advanced. Shoot for 12-14 BTDC, which means you need to retard the timing from where it is.

The distributor slips into the back side of the oil pump housing. Inside the housing is a spring that is there to bias the oil pump impeller forward. The side effect is that it's also pushing on the distributor, and will push it out of the housing if the clamp is loosened. Any time you loosen the clamp, first apply inward pressure with one hand while you loosen the clamp with the other hand. Maintain full-time inward pressure until the clamp is firmly tightened again.

If the distributor partially pops out, it can disengage from the drive, and the rotor will not turn with the engine. In that case, the engine will not start.

Remove the distributor cap, grasp the rotor, and try to rotate it. If it's solid and doesn't rotate, then the drive is still engaged. That's good. If the rotor/ shaft does rotate, then the drive has disengaged, and the first task is to properly re-install the distributor. Raise your hand if we need to go there.
mcguan.2 wrote:1. I'm pretty sure the PO rotated the distributor to switch from Strombergs to Dellortos. What way should the distributor (or more importantly the knurled nut) be facing? My knurled nut faces almost straight down towards the ground.Ignore the knurled nut and which way it's facing. The distributor clamp must be loosened, and the entire body rotated to get the timing right.

As you look at the top end of the distributor (where the plug wires attach), retard is Counter-Clockwise (CCW), and advance is Clockwise (CW).
mcguan.2 wrote:2. If I have to make a large degree change in the static timing, like it would appear is the case here, is rotating the knurled nut enough? Or do I need to rotate the whole distributor cap? And is that how this distributor works? It would appear not, since it has the clips on the side. That said, what's my best option for getting from 29 degrees to 12? And any pointers for reaching and turning the knurled nut? It's tight quarters down there and hot, to boot.Forget the knurled knob, for now it doesn't exist.

The entire distributor body must be rotated, and the cap will go along with it. It's impossible to rotate just the cap. There's a tab inside it's rim that fits into a notch in the distributor body. The cap only fits one way, locks into place, and is held on by the spring clips.

Looking at the top of the distributor cap, 29 BTDC means it is now rotated too far clockwise. It must be rotated about 18 degrees counter-clockwise (18 is an arbitrary 'even' number for easy math... stay with me).

All timing events are measured in crankshaft degrees. The distributor rotates at half engine speed, so retarding the timing 18 degrees means rotating the distributor body half that, or 9 degrees counter-clockwise (CCW).

*~*~*
"IF" you have absolute confidence in the 29 BTDC timing you mentioned earlier, you could just rotate the distributor body 9 degrees CCW and be close. My confidence in that is a little shakey.

If you can't eyeball 9 degrees, then look at the auxiliary timing belt pulley (the one that drives the oil pump and distributor). The teeth are 9 degrees apart, which equates to 18 crankshaft degrees.

Eyeball-align some feature on the distributor body with a pulley tooth (or use a ruler/ straight edge), then loosen and rotate the distributor until that feature aligns the same way with the next tooth counter-clockwise. Tighten the distributor clamp.

Re-check the static timing, and it should now be about 11 BTDC (29 - 18 = 11).

*~*~*
A better way would be to follow Mr. Rosenbaum's advice (when you have some time, read all his old posts). This message is getting a little long, so I'll get into that on the next page.

Regards,
Tim Engel

Last edited on 01-26-2015 03:30 am by Esprit2

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 Posted: 01-21-2015 05:28 pm
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Esprit2
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Mark Rosenbaum wrote about using a multi-meter. That will work, but I prefer to use a continuity light. The light only requires peripheral vision, while a meter (to me) demands more attention.

Connect the light between one of the 12v terminals on the coil and a good ground... like the engine block.

The coil gets 12 volts from the ignition switch, then it's ground wire passes through the distributor on it's way to ground. The breaker points or the electronic ignition amp switch the ground wire on and off. On charges the coil, and off causes the magnetic flux field to collapse, firing the spark. What you're looking for is the instant it switches off.

With the points/ amp 'on', the current has another path to ground besides going through the continuity light. Depending upon the Watt rating of the bulb, it may burn dimly, or not at all. When the points/ amp switch 'off', all of the coil's current has no where to go but through the light, so it will either get brighter, or turn on. Both "dim-to-bright" and "off-to-on" tell you the same thing... the points/ amp just switched off (fired the spark).

1) Set the #1 cylinder to TDC. Looking at the front of the engine, rotate the crankshaft in it's normal direction of operation (Clockwise... CW). A 19mm or 3/4" socket on the V-belt pulley bolt head is an easy way to turn it.

Next to the V-belt pulley, at the 10-11 o'clock position, there's a metal tab with timing marks cast into it: 30... 20... 10... 0 (0 = TDC). And there's a notch cut across the outside rim of the pulley, front to back. No matter how many v-grooves the pulley has, the notch goes all the way from front to back. The notch is the moving pointer, so align it with '0' on the number scale. Cylinders 1 & 4 are now at TDC.

Now look at the timing dots on the rims of the cam pulleys. If the dots are adjacent to one another, and on the imaginary centerline between the cam centers, then it's cylinder #1 that's at TDC... what you want.

If the dots are on the centerline, but on far opposite sides of the pulleys, then #4 is at TDC. Rotate the crank through one more CW revolution, and back to TDC. The pulley timing dots should now be next to one another, and #1 is at TDC.

The #1 cylinder is the one at the front of the engine, closest to the radiator. Grab it's spark plug wire, and follow it to the distributor cap, noting to which terminal it's attached. Release the snap clips and remove the distributor cap. Note where the rotor is pointing.

Note: Even when perfectly timed, the rotor won't point directly at a terminal at TDC... on center. The rotor has a wide metal terminal on it's end, and it rotates CCW as you look at the top of the distributor. When timed, the leading edge of the rotor's terminal will be aligned with the cap's terminal, making the rotor look like it's off-center. So imagine the rotor is moving CCW, which cap terminal is it just approaching. That terminal "IS" #1.

Since the distributor isn't timed yet, the rotor may be between terminals, and you have your choice. Since the #1 plug wire is already attached to one terminal, it makes sense to target that one. Since you measured the static timing as way advanced at 29 BTDC, expect to see that the rotor has already passed that #1 plug wire terminal and is moving away from it CCW. Rotate the distributor body as required to put the terminal just CCW from the rotor.

If there were no plug wires attached to the cap, you could choose any terminal as #1, and align it just CCW from the rotor, as above. That would now be #1, so install the #1 spark plug wire there. Then the rest of the wires go clockwise around the cap in 1-3-4-2 order. Replace the cap.

The only reason for setting the engine to TDC was to confirm the #1 cap terminal, and the plug wire installation.

2) Rotate the crankshaft in it's normal CW direction one more revolution, stopping at the desired Static Timing. If you want the static timing to be 14 BTDC, then set the notch on the V-pulley rim next to 14 on the metal timing mark tab. This time it doesn't matter where the cam pulley dots are since the distributor will fire at TDC for both #1 & #4. You can time the distributor using either one.

3) Attach the continuity light's alligator clip attached to one of the coil's small 12-volt terminals. Turn the ignition key to on/ run. Left hand on the distributor cap, apply inward pressure on the distributor (remember the spring?). With your right hand, loosen the distributor clamp enough that the distributor can be rotated in the oil pump housing. With your right hand, pick up the continuity light and press it's ground probe against the engine or other good ground.

4) Rotate the distributor Clockwise (CW) until the light goes brite or on. Reverse and go CCW until the light goes dim or turns off. Go back and forth a few times until you get a feel for the switch point.

5) Rotate the distributor CCW until the light goes dim/off, and a little more to allow for any slop. Reverse, and slowly go CW, watching for the light to on/ brite. Stop the instant it does. If you have any doubts that you stopped at the exact point, then back up and try again. When satisfied, put the light down and tighten the distributor clamp. The static timing is now 14 BTDC... or whatever value to which you set the crank timing.

Turn the ignition switch off right away.

NOTE: When the engine is running, the points/ amp is constantly switching the coil's ground wire on-off. Therefore, the points/ amp don't carry the coil's current full time, and don't get dangerously hot. But if the ignition is switched on while the engine isn't running, it's possible for the points/ amp to be in the 'on' position for an extended time. Be aware that the Pertronix Ignitor (not the Ignitor II), can NOT tolerate full coil current for very long, and will permanently fry in only a few minutes (10... guessing).

So don't dilly-dally. Get your ducks all lined up in a row, tools all laid out, and steps memorized. When you're ready, then switch on, do the job, switch off. Allow no extra "on" time. The Ignitor amp is the worst risk. But if the power is left on long enough, the dumb old breaker points can be burnt as well.

Mark Rosenbaum's procedure with the meter is the same, except you're looking for a change in the reading. With a little adjustment to your thinking, you can use the voltmeter, ammeter, ohmmeter or continuity meter functions. Anything that reacts when the points/ amp switch a 12-volt ground wire on-off.

*~*~*
Now that you're done, that knurled nut/ knob can come into play if you wish. Some distributors have them, some don't. On some distributors, what looks like an adjusting nut is really just the mounting nut for the vacuum capsule. When an adjuster is present, they're just a convenient fine adjustment with a very limited range. Get the timing as close as you can by rotating the distributor body, then use the knurled nut to fine tune to perfection. But when the static timing is 29 BTDC, it's not even within shouting distance of the knob's effective range. Take care of the big changes before worrying about any knob.

Regards,
Tim Engel

Last edited on 01-26-2015 03:29 am by Esprit2

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 Posted: 01-25-2015 12:41 am
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mcguan.2
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Wow. This is exactly the type of step by step instructions I need. I would consider myself a novice mechanic at best. To answer a couple of your questions. I do not know if I have the petronix ignition. How can I tell?

Also, as for determining the static timing, I youtubed some videos and based off the relationship of the four marks on the pulley (as noted in the shop manual) and the grooved V pulley, I determined that at idle they lined up just shy of the fourth notch on the pulley (the one closest to me as I was standing on the passenger side, leaning over that fender), which would have been the 30 degree mark, no?

Of course that was when I was able to get it started. When you described what happens when the dizzy cap is popped off, that probably happened to me. I was having difficulty getting it started after a long layoff and a lot of rain, and someone suggested there might have been water that got into the cap, so I pulled it off to check, not knowing the repercussions.

I plan to take all of your advices and give this a shot on my next day off, and I'll report back how it went. One more question, the coil has wires connected to all of the terminals. When attaching the test light, do I pull something off, or just try to grab one of the nuts that holds the terminal? And do I want to put the clip on the positive side of the terminal and the negative to the frame? That would make sense, but in one of Mark's posts he mentioned hooking up to the negative side. I didn't understand that.

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 Posted: 01-26-2015 03:29 am
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Esprit2
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user=1922]mcguan.2[/user] wrote:I do not know if I have the petronix ignition. How can I tell?.Remove the distributor cap and look inside. If there are breaker points present, then there is no electronic ignition installed. If there is a red plastic cube, or similar, where the points would normally be, that might be a Pertronix Ignitor amplifier. Look for a name on it. If there is neither breaker points, nor a red cube present, but there's some funky looking stuff in there, or several wires going to an external amplifier box... then post a picture. You really need to know what you're tuning before you can tune it.
mcguan.2 wrote:Also, as for determining the static timing, I youtubed some videos and based off the relationship of the four marks on the pulley (as noted in the shop manual) and the grooved V pulley, I determined that at idle they lined up just shy of the fourth notch on the pulley (the one closest to me as I was standing on the passenger side, leaning over that fender), which would have been the 30 degree mark, no???? I'm not sure I'm following all of that. Were you using a strobe light to view the timing mark while the engine ran at idle? If so, then having the notch in the V-belt pulley align with the timing mark closest to you (30 BTDC) would have been about where you say. Is that what you did?
mcguan.2 wrote:Of course that was when I was able to get it started. When you described what happens when the dizzy cap is popped off, that probably happened to me.Nothing happens when the distributor cap is removed. It's when the clamp that holds the distributor into the oil pump housing is loosened that the spring pushes the distributor out, disengaging the drive. You can remove and replace the cap with little risk.
mcguan.2 wrote:I plan to take all of your advices and give this a shot on my next day off, and I'll report back how it went.Do you have a friend or co-worker who is more mechanically skilled who could help you with this. You seem to be lacking a basic understanding, and it would be best if you had someone there with you rather than posting on a forum.
mcguan.2 wrote:One more question, the coil has wires connected to all of the terminals. When attaching the test light, do I pull something off, or just try to grab one of the nuts that holds the terminal? And do I want to put the clip on the positive side of the terminal and the negative to the frame?The test light is connected between any positive voltage on the coil, and a good round like the engine block. Positive voltage is connected to the coil's (+) terminal. Then resistance in the coil drops that to a lower voltage at the (-) terminal. But compared to ground, but the (+) and (-) terminals are still positive... one is just higher voltage than the other. For what you're doing with the test light, either terminal will work.

No need to remove any wires "IF"...
1) the wiring present is stock, as shown in the electrical schematic.

2) the wiring is stock, plus that required to install a Pertronix Ignitor electrronic ignition system.

If someone has added a bunch of other wires for some aftermarket add-on, then I have no idea without knowing what's there.

Presuming your car is stock with breaker points, or with just a Pertronix Ignitor installed, then simply connect the test light to one of the small terminals on the ignition coil. Most purchased test lights have an alligator clip on the end of it's positive wire. Just clip it to one of the terminals.

Good luck,
Tim Engel

Last edited on 01-26-2015 03:35 am by Esprit2

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 Posted: 01-26-2015 04:02 am
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mcguan.2
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Unfortunately, my mechanically-inclined friend (and JH owner) moved to Vancouver a couple years back, so I'm on my own. I think I misspoke when I was talking about removing the distributor cap. I unfastened the long clips that runs the length of the distributor. Those are the ones that would have let the distributor pop out of place?

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 Posted: 02-14-2015 07:52 pm
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mcguan.2
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So upon removing the distributor cap, I see it is petronix, and the rotor inside just freely rotates, so I set about trying to re-seat the distributor. Unfortunately, I was only able to wiggle and twist it in as far as the picture shows, with about a 1/4" gap at the rear end. Is this as far as it should go? No matter how hard I try, I can't cajole it past that point, and the rotor is still freely spinning.

Attachment: Distrib.JPG (Downloaded 82 times)

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 Posted: 02-14-2015 11:14 pm
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mcguan.2
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Figured it out. The clip had closed itself down and was keeping the distributor from being able to push all the way in. I had to pry it open some more with a pair of pliers to get it over the distributor body. Managed to complete your instructions and now static timing is 12 degrees BTDC. Thanks for the help on that one.

Unfortunately, it still struggles and spits at low throttle. When I hammer it, the problem goes away. So, next step would be to check the balance on the carbs??

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