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1933 plymouth vacuum test - head removal


Crazyred

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Soooo, I performed my first successful vacuum test, ever.  I read and watched videos to research what I should do and have not seen the results that I had. 

 

First, let me tell you what I have done to the car so far.  It's a 1933 plymouth pd with a 1934 PE or PF engine.  The engine serial number clearly looks like it's PF but looking closer, it looks like it could be PE.  Either way I believe they should be close to the same engine in specs?!?

20210310_201330.jpg.4c8649d8d1bf46bda0c168fb7429bee9.jpg

 

I have changed the plugs, points, rotor cap, and set the dwell to 36.2 degrees (which is another first).  After watching @keithb7 video (thanks keith for the video!!) and seeing that the accelerator pump should give an extra squirt of fuel from idle when accelerating, I rebuilt the carburetor.  This resolved the carb stumble from a dead stop to accelerating.  Also, found other issues within the carb as well and corrected.  I have not been able to check / set the timing and I am sure that is needed.  I looked at the flywheel for timing marks but found none.  I checked the crank pulley for the same but only found a white dot when it's at tdc for the #1, verified by rotor pointing to #1 plug.  If there are no timing marks to be found, what other ways can I verify the timing?  This is one reason I performed the vacuum test but as you can see in the video, there may be other issues within the engine. 

 

When I performed the test, I had the engine up to temp and the hose connected to the intake manifold below the carb.  As you can see in the video, I adjusted the air / fuel mixture screw with no changes to the engine performance.  I did while the engine was running, unscrew it all the way out and the engine died (not shown in video).

 

With the erratic readings shown in the video (sorry for the poor camera shots) I am not sure what to do next and what it means. 

 

Any and all feedback is appreciated!

 

 

 

 

 

  

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You don't necessarily need to know the exact initial advance for the timing, adjust(advance) until you have the best vacuum on your gauge, back it off if you can hear knocking. If you do want to know the advance in degrees, get yourself a dial-back timing light.

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On the 1933 PC, PD and, I think, the 1934 PF models there is a cover on the flywheel housing near the starter. Loosen the bottom (?) screw and rotate the cover to expose a pointer. Timing marks are on the flywheel. A real pain to see them to get the engine rotated to TDC to set the static timing. And impossible to see them if the automatic clutch is installed. I find it easiest to remove the spark plugs so you don’t have to fight the engine compression then use the hand crank to rotate the engine to TDC. I have the distributor cap off when doing this so I can see I am on the correct plug for TDC instead of being 180° off. Though thinking about it, it might not matter.

 

I think on the PE models (equipped with the automatic clutch) the timing mark was on the impulse neutralizer (crank shaft pulley).

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Looks like your idle mixture adjustment isn’t doing anything. Might be because your idle RPM is too high.

 

Looks like your car’s body is Bahama Green but with black fenders. Not a color combination that came from the factory for the PD. I am probably the only person that would notice that. :)

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Just now, TodFitch said:

Looks like your idle mixture adjustment isn’t doing anything. Might be because your idle RPM is too high.

Yes RPM are too high and and mixture screw not responsive due to vacuum leak. Valves are not closing properly revealed by fluctuating needle. Notice how engine noise correspond with gauge readings.

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You can set the timing mechanically.  The service manual has the procedure.

 

Alternatively, if you are sure that dot is indeed at TDC for #1 you can use a dial back timing light to set the timing, assuming they will work with 6vv positive ground systems.

 

Also, there are timing tapes you can use, but I have had no success with them staying on for long.

 

https://www.onallcylinders.com/2020/07/10/how-to-use-a-dial-back-timing-light-2/

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5 hours ago, Sniper said:

. . . Alternatively, if you are sure that dot is indeed at TDC for #1 you can use a dial back timing light to set the timing, assuming they will work with 6vv positive ground systems. . .

I power my timing light from a 12v source and simply clip the spark plug lead on the 6v+ car. Works fine.

 

The issue with 1933 and, I think, 1934 is that the timing marks are on the flywheel and can be hard to see. Again, as I noted above, the PE might have the marks on the pulley but I am not sure about that.

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Just now, TodFitch said:

I power my timing light from a 12v source and simply clip the spark plug lead on the 6v+ car. Works fine.

 

The issue with 1933 and, I think, 1934 is that the timing marks are on the flywheel and can be hard to see. Again, as I noted above, the PE might have the marks on the pulley but I am not sure about that.

Works fine. Used to that until got hold of a battery operated timing light. These are for sale cheap on eBay.

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Good work there @Crazyred, digging in and getting it done. 

 

I went through some similar issues with my '38. I'll share some of my thoughts to give you some ideas to check.  Here's how my tiny brain grasps the sujecct matter:

 

When you rebuilt the carb did you soak it somehow, in a cleaner with all the plugs, balls and screws out? At the base of the carb is there an adaptor? There are vacuum  passages in there. Mounting gaskets, spacer plates, adaptors, heat shields, etc, have recesses cut away and must be lined up to prevent blocking of the vacuum passages. This passage allows vacuum to sort of get up and around the main throttle valve when it is closed. Via an internal tunnel bored into the carb body. A tiny hole or two, can be seen in the carb wall, right near where the throttle valve contacts the carb wall. Right below the throttle valve, when it is fully closed.  This little port, allows fuel to enter into the intake manifold below the throttle valve. This happens at idle when the throttle valve is fully closed. 

 

I think you physically adjust how much fuel/air enters into the intake when the main throttle valve is fully closed, by opening and closing the air/fuel mixture screw. This adjustment only tweaks A/F mixture at idle, and just a tad, a hair off idle. As you slowly open up the main throttle valve, the low pressure point (vacuum) travels farther up past this tiny fuel inlet port. The engine really starts sucking in air now. It wants more and will take all you will allow it, until it blows up. Yet we maintain control of air and fuel intake via the carburetor. An engine won't run on air alone of course. So we mix fuel in with it. As precisely as we can. Within the limitations of a carburetor.

 

 As the main throttle valve opens, the fuel now enters the carb higher up the throttle body. Possibly 2 different inlets now. Larger openings called jets, allow way more fuel in, compared to the tiny port at idle. These jets are precision drilled holes that allow a specific amount of fuel in. As you open the throttle, linkage connected to the accelerator pump gives it a good squirt of raw fuel. It may have its own inlet, or may force the raw fuel out through the main fuel intake. You may see this happening up high in the intake, further down below the choke. The carb intake necks-down just below the area, speeding up the air flow. Creating more vacuum up in this area. Also atomizing the raw liquid fuel. The top of the fuel bowl is vented to atmospheric pressure. The carb venturi is well below atmospheric pressure. This phenomena causes fuel to flow in the carb through the main jet now. 

 

All the parts of the carb, from the intake down, have to be sealed up air tight. All the sandwiched layers, plates, adaptors, etc must have proper gaskets so air cannot enter the carb via any other way, except through the controlled ports.  If air enters via some other opening, we then loose control of the incoming air. This takes away vacuum pressure from the ports where we need it. At the idle air mixture screw for example. You twist and turn the idle A/F mixture screw and nothing happens, until you close it all the way and the engine may stumble. That's a good sign of a vacuum leak elsewhere.

 

When you tweak the other screw on your carb, the idle speed screw, you are locking open the main throttle valve. Just moving it slightly and holding it there. As you open that valve, vacuum travels further up into the carb and starts drawing fuel in from the main jet. Some carbs may have an intermediate jet. Its main use is to deliver fuel in the zone between idle and the main jet delivery. If the car runs at higher idle as you turn up the idle speed screw, yet won't at low idle,  that is another sign you have an issue with the jetting or internal passages drilled in the carb. Something may be plugged up with foreign material, or you may have a vacuum leak.

 

The stumble showing in your vacuum gauge. I agree with what others have said. I think you have valve sealing issues. Intake valve sealing issues. The intake valve is supposed to be 100% closed and sealed when combustion occurs. This little controlled explosion, will push exhaust gasses out of the cylinder any where it can. An unsealed intake valve would allow gasses to travel back into the intake manifold. Forcing your needle to move in the the opposite direction. This happens quickly of course, with each cylinder that may have a valve leak. The vacuum gauge needle flutters as shown.

 

Have you completed a compression test yet? Both wet and dry? What are the results?

 

Here's an example of a vacuum leak I found at the carb base mounting area. You can also see two vacuum ports, drilled holes, at the right side of this adaptor plate.

 

IMG_8968.jpg

Edited by keithb7
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Wow, I appreciate all the feedback on this!!! ?

 

I was hoping it might be something other than possibly having to tear in to the engine but that may be the end result.  After reviewing the above links and info, looks like it points to these areas: possible bad head gasket, valves and/or valves guides, or vacuum leaks.

 

I will start simple and check for vacuum leaks and timing issues first.  For the vacuum, I have three sources / areas for possible leaks, the distributor advance is vacuum (autolite distributor igs-4003-1 from later plymouth engine), intake / carb area and intake manifold gaskets at the block.  Does this sounds correct?

 

I'll check the flywheel for timing marks again.  When I open the cover plate, it has a timing pointer plate as well with the pointer on one end.  The plate can be installed in either direction and that would make the pointer at the top or the bottom of the hole.  Which end should it be closer to?  I will also check the crank pulley closer and clean off some rust to identify any markings.  Hopefully I can find markings on one of these areas.  If not, I will have a new adventure with a back dial timing light.

 

What should the idle rpm speed be for these engines?  After setting the idle adjustment, I will readjust the mixture screw since it has no impact currently.

 

Keith, thanks for the thorough write up.  When I cleaned the carb I was able to soak it in a 1 gallon carb solution for over an hour.  I had it completely disassembled and soaked all items and blew out all areas and tubes, etc with canned carb spray until it was clear.  The carb was dirty and had several areas clogged but now is cleaned.  I bought a rebuild kit from Hal Houghton which had all new gaskets as well.  I removed the carb after installing to check the alignment of the intake/carb gasket.  The gasket aligns with the single hole on the base of the carb so I think it's good in that area.  I have not completed a compression check but adding that to my to do list.

 

After the above steps are complete and I have the same vacuum result, I will move on to the valves.  I would assume I would need to check the valve clearances and adjust as needed (another first for me).  How would I be able to tell if the valve guides are worn out?

 

As always, the advice is greatly appreciated and always impressed with the knowledge from everyone in this forum!!!

 

 

 

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On 6/15/2021 at 11:25 PM, TodFitch said:

Looks like your car’s body is Bahama Green but with black fenders. Not a color combination that came from the factory for the PD. I am probably the only person that would notice that. :)

 

Todfitch, I always wondered about the original color of the car.  I have a request in to Chrysler Historical for the build card but they are out due to covid but hopefully returning this summer.  It's so interesting to see what has been done to these cars over the years to keep them running!

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2 hours ago, Crazyred said:

. . . the distributor advance is vacuum (autolite distributor igs-4003-1 from later plymouth engine . . .

I think the static timing will depend on the distributor installed, so you should look up the specifications for that particular unit.

 

Also, the 1933/34 carburetors don’t have the vacuum port for a vacuum advance line to the distributor (mechanical advance only for those years). Do you have a later carburetor too? If so that model carburetor’s adjustments and settings should be followed. If using an original 1933/34 carburetor, where is the vacuum for the distributor coming from? (In your video I did not get a good look at the top of the float bowl to see the characteristic differences between the 1933/34 carburetors and the later ones.)

 

2 hours ago, Crazyred said:

. . . I'll check the flywheel for timing marks again.  When I open the cover plate, it has a timing pointer plate as well with the pointer on one end.  The plate can be installed in either direction and that would make the pointer at the top or the bottom of the hole.  Which end should it be closer to? . . .

I am attaching a photo from the 1934 factory service manual (shows two pointers) and a photo from my '33 (only one pointer).

 

2 hours ago, Crazyred said:

. . . What should the idle rpm speed be for these engines?  After setting the idle adjustment, I will readjust the mixture screw since it has no impact currently. . .

 

Original owner’s manual isn’t much help here. It says nothing about what the idle speed should be. Actually, I can’t find any pre-WW2 specification for that. My guess is that inexpensive tachometers were not available in that era and mechanics just did it by feel and experience. The 1946-54 factory service manual says 450 to 500 RPM for idle which is what I set mine too.

 

Also, in your video you seem to be cranking down pretty hard on the idle mixture screw. Neither the brass screw nor the die cast carburetor body are very hard metals and by cranking down on the adjustment you are likely to be damaging either the seat or the screw tip or both. Be gentle there!

 

IMG_1497.JPG

IMG_1496.JPG

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Interesting. Just noticed I have a bolt (officially a “hexagonal head cap screw”) holding my timing cover on while the 1934 service manual shows what look like round headed screws.

 

Just looked at both the 1928-1933 and 1934 parts books and both show the fastener should be part number 120854 which is a hex head cap screw. I wonder why the illustration in the 1934 book shows a round headed screw.

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20 hours ago, Crazyred said:

 

 For the vacuum, I have three sources / areas for possible leaks, the distributor advance is vacuum (autolite distributor igs-4003-1 from later plymouth engine), intake / carb area and intake manifold gaskets at the block.  Does this sounds correct? 

 

From the top of the piston compression rings, when at BDC (bottom dead center) all the way to the top of the carb air intake, all points in between, has potential for a vacuum leak. Some areas are obviously not going to have a vacuum leak. Like a cylinder wall. Yet a cracked block here in theory could coolant entry and you'll burn it. It could also blow bubbles the other way, into the coolant. Anything that plugs into, threads into, bolts to or clamps to, items related to this air intake path, has potential for a vacuum leak.

 

Examples may include: an intake manifold vacuum test port plug. Threads stripped? Missing? Incorrect piece of something or other jammed in there? All gaskets between all parts. Vacuum wiper hose and related parts. Vacuum advance lines, connections, fittings,  hole thru advance diaphragm at distributor? Yes intake manifold gaskets. Leaking/incorrect idle air fuel mixture screw. Loose manifold fasteners? Do you have a vacuum booster pump? Potential for leaks at connections and hoses there too. Loose spark plugs? Cracked intake manifold? Missing carb parts. Worn sloppy carb throttle valve linkage?...Some examples.

 

I have not completed a compression check but adding that to my to do list.

Best to do it early. A compression test can tell you really good info that will direct you down the proper path for a repair...The first time.

 

 I would assume I would need to check the valve clearances and adjust as needed (another first for me).  How would I be able to tell if the valve guides are worn out?

 

The cylinder head comes off. Valve covers come off. Valve spring retainers and springs are removed. Valve sits freely in the guide. A dial gauge is mounted near the valve edge and set at zero. You wiggle the valve sideways, toward the dial indicator pin. Movement is recorded.  My Motors Manual states the following for valve/guide clearance for a mid-30's Plymouth: Intake 0.001 - 0.003" Exhaust 0.003" - 0.005". Why more for exhaust? The exhaust valves get very hot and hot metal expands. So more clearance is required. I have measured a brand new intake and exhaust valve stem. The exhaust valve stem is  0.001"  smaller diameter than the intake.

 

Both the valve guide and the valve stem can wear. So does the end of the valve stem where it contacts the tappet. The valve may eventually start to skew/yaw in its guide, causing valve seal-ability issues up at the top end. We're talking thousands of an inch here. You won't see it with the naked eye. Imagine a long drinking straw in a tall tapered glass of soda. It leans on an angle toward once side of the glass. This is is an exaggerated example of a worn valve stem, leaning in a worn guide. 

You can see the results in the valve surface-to-seat wear pattern area. It all adds up to slop. Which leads to poor valve sealing. Leading to low engine compression numbers. Leading to a bouncing vacuum gauge needle! I'm not saying this is your problem, just adding some context to the topic.

 

Why valve guides? Why not just machine a hole it the block and let the valve run through it? Because valve train parts wear. As mentioned, a sloppy valve, worn out of spec, may ride the guide. It sure is nice to pop those worn guides out and replace them. The block is now able to be refurbished to new specs. Versus tossing out the spent block. I can't say for sure, but I'd wager early engines may not have had valve guides. Then someone came up with the idea and improved it. I make it sound easy to remove/install new guides. It's not a breeze. Yes it can be done at home. Due to an interference fit, a lot of force is needed to install new guides. Freezing them to -50 or so helps.

 

When installing brand new valves into guides of unknown service life, it can get annoying. Imagine descending a long hill in low gear. The carb throttle closed. The engine  is dynamic braking, hold you back. Blue smoke (oil) starts billowing out the tail pipe. You get to the bottom, rev up the engine. Clean it out. Then the blue smoke is gone.  These days many folks don't take kindly to smoking old vintage cars. It's a poor image for the old car culture. 

 

Quote

 

 

 

 

 

Edited by keithb7
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  • 2 weeks later...

Well finally had some extra time and was able to work on the car again.  Received a useful father's day gift and wanted to give it a try but first I completed my first dry compression test for the car and myself.  I performed the test twice to make sure that I did it correctly and received the same results for both tests.

 

The results:

#1 - 95

#2 - 92

#3 - 100

#4 - 91

#5 - 90

#6 - 93

 

I would assume that these numbers are acceptable?  Also, cleaned and gapped the plugs while they were out.

 

Now to play with my gift, a new vacuum gauge!!

 

 

As you can see the readings are different with this gauge.  I have not changed anything other than gapping plugs and lowering the idle by ear since the last test, so maybe the other gauge caused some fluctuations?  The car has a miss in it, so I checked the timing.  First, I opened the window on the flywheel once I had it TDC and found no markings.  @TodFitch my window is similar to yours but the timings specs are different on the pointer plate, which should be expected since it's a  1934 engine.

 

20210625_130045.jpg.c454a76357b80cf56e3f4883342b32d4.jpg

 

 

I moved on to the crank pulley to look for markings.  I figured I would remove the alternator (no generator on this car) to make it easier to hunt for markings.  After some scrubbing and sanding, I was able to see markings by the existing white dot.

 

20210625_132915.jpg.01e48662528adcfc7d40e7f4ff03c61f.jpg

 

 

So to help my old eyes, I added my own markings at every 5 degrees and a line at TDC and 3 degrees after TDC which is the settings for this engine.

 

20210625_150317.jpg.27809485cf83dfda77fe3b86ffa200b0.jpg

 

After reassembly of everything, I placed the engine on the 3 degree mark, checked the points setting at .020.  Started the engine again and the miss is still there.  Adjusted the dwell to 36 again and no change.  Loosened the distributor and rotated and no major improvements.  Rechecked all vacuum connections and no obvious leaks.  I went so far as to take the carb off again and check the internals to verify that I reassembled it correctly the last time.  Found no issues and after reinstalling the carb, still had the miss.  Frustrated by this point, I decided to remove the distributor after setting it to TDC.  Once removed, I checked the vacuum advance diaphragm and could not pull a vacuum on it.  So there would be one source of a vacuum leak @keithb7and @chrysler1941.  Just to mention, I replaced the tubing for the vacuum advance a couple of weeks ago as the other one had some pin holes in it.  Also, this engine has a Carter BBR-1 carb with a vacuum port, not original for this year.

 

VideoCapture_20210627-165849.jpg.d96c41e81f607fced49b2e3e46ec0bab.jpg

 

So, I will try to find a new vacuum advance or have this one rebuilt.  I went through the distributor and cleaned, greased, added new condenser and gave it a new coat of paint.  While this is out of the car, what's needed in order to set the dwell on the bench?

 

20210627_163536.jpg.0b90bb9722d985574d60778f9e5de67e.jpg

 

 

Once I have things back together with a new vacuum advance, I'm hoping this corrects the miss!?!  What else should I be looking at?

 

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Feeler gauges will set the initial dwell on the bench.

 

A miss is when for some reason a cylinder doesn't fire.  A number of things can contribute to it.  Bad plug, plug wire, distributor cap, etc.  If it where fuel related it's generally worse than just a miss.  Sometimes a miss can be as simple as running the plug wires to close together.

 

Easier way to find a miss is to hook your timing light up to each plug wire one at a time, let the light flash and see if no flash happens when you hear the miss, that'll be the cylinder that's acting up.  An old school engine scope would see it on the trace.

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One step at the time. Forget timing for now. You have a more serious issue.

As mentioned before, your miss correspond with vacuum gauge and rpm. One or more valves are not closing properly. Watch needle in beginning of video. 

Plug distributor vacuum port and set at TDC. Find cylinder with leak down test. Fix it and then mess with timing and advance curves.

 

 

vacumm-reading-1-768x1045.png

Edited by chrysler1941
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You can also isolate a cylinder misfire using insulated pliers to pull one spark plug wire off the plugs one at a time.  A properly firing cylinder will cause the engine to run worse with the lead removed. If you pull a wire and the condition doesn't change that indicates that cylinder is one of the misfires. Unplug, asses the miss, and reattach the leads till you find the one or more culprits.  A compression check of suspect cylinders can then indicate if the miss is mechanical like a stuck valve, or electrical.

Edited by greg g
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One other place to remember for a vacuum leak is the windshield wipers, if it still has the vacuum wipers on it.

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  • 3 weeks later...

 

Latest update.

 

Received new vacuum advanced for distributor.  Used my mityvac hand pump and set the curve which actually turned out to be the same amount of spacers as in the original.  Set the points and oiled and greased the necessary areas.  Reinstalled the distributor, rotor and cap. New plug wires are in the mail and will be installed soon.

 

Using the steps quoted below, I set the timing on the engine:

 

On 5/21/2011 at 12:15 PM, Bradley S. said:

I don't remember where I got this information. Probably off the net partialy and partially from one of the great minds here on the forum. This is how I timed my truck engine with vacuum. Remember to set the points dwell first, then time.

Brad

Timing Engine Using Manifold Vacuum

Older engines can't always be tuned or adjusted per their original guidelines. Timing chains can slip over the years, harmonic balancers can move, and the bottom line is you are no longer able to verify where top dead center is using the old methods. Plus, with today's fuels, it's more difficult to reach the point where your old engine performs both efficiently and reliably without sacrificing performance. Following the steps below, you will be able to minimize pinging, have reliable starting under all conditions, and easily get maximum performance from your engine using today's fuels.

1. Connect a vacuum gauge to a vacuum source directly on the intake manifold. Do not attach gauge to ports being used by any other device. Plug any vacuum lines you remove from manifold to make this connection.

2. Loosen the bolt securing the distributor so you can turn the distributor to adjust the timing.

3. Start the motor, let it warm up to normal operating temperature, and stabilize at normal hot idle. Using the idle speed adjustment at the carburetor, set the idle speed as low as possible without stalling the motor. Disconnect the distributor vacuum advance and plug the line.

4. Keep in mind when adjusting the timing, you have to turn the distributor clockwise to advance and counter-clockwise to retard.

5. While watching the vacuum gauge, slowly turn the distributor clockwise (advance timing) and look for a maximum reading on the gauge. For instance, if the reading on your gauge peaks at 18 inches of vacuum, that is the maximum for your engine. (The normal range could be from a high of 20 inches to a low of 15 inches, depending on the internal condition of your motor). The reading will drop off if you advance too far, so turn the distributor counter-clockwise (retard timing) to go back to the peak reading on your gauge.

6. Once you have established the peak reading, retard the timing (turn distributor counter-clockwise) to reduce the reading by about 1 inch to reduce ping. You may need to reduce the reading by 1.5-2 inches total, or even more, depending on the fuel available in your local area. Let your engine's performance guide you. If you had the same 100 octane fuel in your tank that was available when these cars were new, you would most likely leave the timing at the peak vacuum reading, but even when these cars were new, there were issues with fuel. Old Technical Service Bulletins (TSBs) exist that recommend retarding timing due to engine ping, so this was a concern even back when the cars were relatively new. 

7. Stop the motor and tighten the distributor hold-down bolt. While you still have your vacuum gauge hooked up, it is a good time to set the idle mixture needles on the carburetor. The adjustment is normally made with the two screws at the front base of the carburetor, depending on model. Turning the screws in will cause a richer mixture, turning the screws out will cause a leaner mixture.

8. Start by turning the two screws in fully then backing them out about 1 1/2 to 2 turns. Start the motor and check the vacuum gauge. What you want to see is a maximum steady vacuum reading. At the beginning stick to adjusting just one screw at a time to achieve maximum vacuum. As you turn the screw in you will see a reduction of vacuum on the gauge. When you turn the screw out you will see an increase in vacuum but only to a point. If you get the mixture too lean the vacuum gauge needle will start bouncing around. Your goal is to have maximum steady readings. Then repeat the process for the other screw. To fine tune, adjust both screws slightly while watching the gauge.

9. Once you have achieved a satisfactory idle mixture, set the idle speed to specification, then remove the vacuum gauge and reconnect any vacuum lines you removed. Don't forget to reconnect the distributor vacuum advance.

Test drive your car and listen for any ping under light acceleration as well as under heavy acceleration. Additional retarding of the timing may be necessary if excessive pinging occurs. You should hear a very slight ping under light acceleration, and none under heavy acceleration. Your engine is now optimally timed to run on today's lower octane, no lead fuels.

 

 

After following these steps I was able to get the following vacuum gauge results.

 

 

Since I have had the car, this is the best that it has run.  The engine is responsive and has power without any sluggishness.  Also a plus, no more black soot spitting out of the exhaust anymore.  I always had an area on the garage floor with black soot spots under the exhaust tailpipe.  Assuming this meant it was running too rich.

 

I still have an occasional slight drop in the vacuum gauge, as @chrysler1941 has previously pointed out.  I was able to get a leak down tester, so I will attempt to figure this out over the next few days.

 

Making progress, learning and having fun!  Thanks again for all the feedback!

 

 

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I notice in your latest video that you have a hose directly from the return tap for a heater on the lower radiator hose to the bypass on the top of the thermostat housing. Sort of bypassing the thermostat bypass. Not sure if that is a problem but if you don’t have a heater I’d cap that off and remove that short hose.

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  • Crazyred changed the title to 1933 plymouth vacuum test - head removal

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