40 Ply Starting Problem

[30U sedan]

I would check the plugs if I was you. If one of the plugs has a burr on the threads it could cause a backfire. The burr gets so hot that it can cause unburned gas to ignite in the cylinder.

[TodFitch]

Hi Don,

Glad to hear you are up and about after your surgery and that the car is now running well.

I have never had to deal with backfire on shutdown, so I can't help much there. One question though: Is it firing back through the carburetor or out the tail pipe? That might make a difference as to chasing down the cause.

--Tod

[Don St Peter]

A couple of months has now past since I reported starting problems on my 40 Ply P-9. Since I am now recovered from major surgery and the car is now running good, I wanted to report to those wanting to be kept informed. Since I did a number of things including 1) overhaul carburator; 2) tune-up including plugs, I'm not sure of the exact problem but those of you that insisted.... If you have fuel & adaquate spark it WILL fire. Thank you.
A special thanks to Tod Fitch who stayed with this novice thur thick and thin.

The only problem I'm experiencing is on shut down. After turning the key off and just as the engine stops turning, I get a significant back fire. Can someone shed some light on what's happening and what to do to fix it?
Again; thanks so much.
Don

[TodFitch]

This seems like it is easier to show than to describe in writing. . . Unfortunately I don't have the technology to take or post a video.

When I do an ignition system tune up I:

1. Rotate the engine around to TDC. I know it is TDC when:
    A. The rotor is pointing to the wire going to the #1 plug and
    B. The timing mark (in my case on the flywheel) is lined up with the pointer. Your mark is on the fan belt pulley but the result is the same.

2. Remove the distributor from the car. I find it much easier to work on the distributor when it is on the bench.

3. Install new points and condenser. I set the points to 0.020 inches gap. I do this by rotating the distributor shaft until the follower on the points is at a high point on the distributor lobes. It should not matter which high spot you use as they should all be the same height. If they are not then the lobes are worn and the distributor needs to be rebuilt. Setting the point gap sets the dwell. On the 1933 PD the specification is for 0.020 inches/36 degrees. I guess you could check it by getting something to spin the distributor but I have never bothered.

4. Re-install the distributor in the car so that the rotor is pointing the same direction as when I removed it. I set the hold down plate so that the screw is centered in the slot. I loosen the side clamp to allow the distributor to rotate with respect to the hold down plate.

5. I attach a test light or continuity tester to the low tension (6v) connection where the coil will later attach. I rotate the distributor until the test light goes out or the continuity tester just stops beeping. This is the point where the point are just opening. Since I parked the engine at TDC this means that my engine is now statically timed to TDC.

6. Tighten the side clamp that holds the distributor to the hold down plate. Attach the coil wire and the distributor cap. At this point the engine should be able to run.

If you wish to make a minor timing adjustment, you can loosen the screw that is in the slot of the hold down plate and rotate the distributor by a few degrees. On my car there is a scale there but I think that was dropped later.

If you are replacing or checking the spark plug wiring, the firing order is 1-5-3-6-2-4.

[Don St Peter]

Todd:
Thanks for the help. Could you clarify a couple of points you made for me.

You said I want the 0.020 inches of clearance on the point contacts to be at the widest opening. You also mention, once installed the distributor body should not rotate easily. The clamp at the base should hold it firmly in place.

My problem is the point openings depend on clocking of the distributor once reinstalled on engine.The distributor can be rotated clockwise or counter clockwise about the loosened screw that goes through the slotted bracket. The point gap thus changes measureably depending on full clockwise or counter clockwise turning of the distributor body. Can you tell me the position from which I start setting point gap. I can then tighten the screw at this position to keep the distributor from the rotation and set gap. Seems the word " dwell" comes into adjustment lingo somehow. Is this what changes with rotation of distributor body about the screw? Can you tell me about it and effect on engine running right.
Thanks in advance.
Don
.

[TodFitch]

Other than tweaking the idle mixture I haven't touched my carburetor in years and my 1933 uses a bit different version of the Carter than yours so I'll leave the carburetor part of your question to other. Besides, 95% of carburetor problems are electrical. :)

I find it easiest to remove the distributor from the car to install and adjust the points. You want the 0.020 inches of clearance on the point contacts to be at the widest opening. I find that easier to get when I am not fighting engine compression and/or the starter when trying to get the distributor cam in the right place.

The distributor can go in two ways: Correct (#1 at top center) and 180 degrees out (#6 at top center). Just remember where the rotor was facing when you pulled it out and put it back the same way.

Timing: If it ran at all then you will be at TDC when you are on the mark and the rotor is pointing to the terminal for the #1 spark plug.

If you can't find the mark on your pulley, then there is a pipe plug over the #6 piston which can be removed. A stiff wire or rod can probe for the top of the piston and will tell you when the #6 (and thus #1) pistons are at top center. Just don't drop wire into the cylinder or you will be looking at a head removal. :)

If it has not run, then set it up with the pointer on the mark (or rod sticking up out the the plug hole at its highest) and assume you are on TDC. If it does not start (and you have good strong spark and gas) the pop the distributor out and rotate the rotor 180 degrees and reinstall.

Once installed the distributor body should not rotate easily. The clamp at the base should hold it firmly in place.

[Don St Peter]

David Pollock provided good info on timing chain:
In follow-up to his posting regarding checking timing, I'm sure my questions as follows will reveal my shortcomings on basic knowledge, but here goes.
1. The marks on my fan pulley are very faint. I'm having trouble locating "top Dead Center" location. I can barely make out the marks. Where is TDC mark or how can I otherwise assure TDC position?
2. Once I get to TDC and remove the distributor cap, how do I determine if rotor is in either #1 or #6 firing position?
3. I am installing new points, rotor and condenser. Assuming timing chain is OK, do I adjust the point gap to .020 with rotor in this position ( 1 or 6 ), or do I adjust gap with rotor in another position?
4. I have noticed the total distributor rotates easily and rotating it clockwise and tightening the screw changes point gap to something different that if I rotate it counter clockwise and tighten it. What does rotating the cap do and what should be it's position when setting the gap to .020?
5. I am also going to disassemble the Carter carb. and soak in cleaner and reassemble with new gaskets. Are there some cautions other than don't end up with pieces left over?

Told You!
Thanks Don

[Don St Peter]

Thank you all for great info. We can discount any "critter" contribution and blown head gasket in my case. During initial investigation, I found some fuel in the oil and have replaced the fuel pump and plugs. I have points, condenser and rotor on order as well as carburetor kit and will be checking timing issue. I will keep you posted on results.
I still tend to be hung up on the "correct" fuel mixture issue since I found the fuel "puddled" in the engine just below the carb. chamber upon carb removal. In my case, I had good blue spark in all the right places and fuel, PLENTY; thus was the reason for my carb. float valve questions and "how" the fuel is actually "misted" into the pistons for combustion questions posed earlier.
Again thanks!
Don

[Jim Benjaminson]

Don - never thought of the possibility until Dave Pollock mentiioned it.  Is it possible you have a collapsed muffler or one packed full by those little 4 legged critters we don't like to see in our old cars.  If it can't exhaust, it can't run.  When I got my '34 out of a 14 year barn rest, the engine would turn over half a turn - either way -- and then jam.  And the windows wouldn't roll down.  Squirrels had managed to get acorns into the flywheel dust cover.  The ring gear would "run" the acorn to the block where it would jam.  And they had packed the inner doors with so much flax you couldn't roll down the windows.  Last fall my daughters car at college develped a strange sound, like someone had dropped a ball down the window defrosters....mice had carried insulation from a nearby building project into the heater ducts.....so its a possibility if all else fails.

[David Pollock]

I didn't mean to alarm you about the timing problem but it is a very real possibility and an easy one to check.  First, let me explain why it is possible.  If the chain is at the end of its life, it will be stretched to the point where it hangs below the smaller gear when at rest. If the engine was fully hot after a long run, this condition may be sufficient to cause the chain to ride up on the top of the gear teeth and thereby jump a tooth, the next time the engine is started.  A stretched chain makes a peculiar rattling sound at idle but this often goes unnoticed.

To check, bring the timing mark for TDC up under the pointer.  Remove the distributor cap and see if the rotor is in either the #1 or #6 firing position. The points should be open or close to it. If everything is right, then it is not the timing chain and you can cuss me out for being an alarmist.  Just remember though, if it has fuel, air, spark and compression and everything is timed right, it has to run.  The only exception to this is if you have a muffler full of water or antifreeze but this only happens after a blown head gasket and you did not say whether or not the radiator was still full.

I had better quit now before I really spoil your sleep.  Good luck, chances are it is something really simple that is so obvious it has been overlooked.    dp

[Go Fleiter]

see float check procedure:
Greetings! Go

[John Hendricks]

Find a straight piec of wood- say 1/2" square that is long enuff to lay across the top of the carb float chamber.  then with a ruler or micrometer find a second piece of wood 5/64 thick.  It  just so happened that a popsicle stick that i was using for a glue spreader was laying there and it measured 5/64 thick so i cut a small piece off and glued it to the underside of the 1/2" square so that it hung down and touched the top of the float.

After thinking more about your problem and what u have discovered, I would wonder if maybe a piece of crud might have enetered the system and is lodged in one of the jets.

If u have access to one of those old blue Motors Manuals, the section on carbs has some good drawings and will help decypher the intracies of the passages thru the carb. Quite ingenious

[Don St Peter]

The float was floating in the fuel. Please tell me more about the "popcycle" stick measurement. Where did you place the stick and where did you measure to? How does the fuel make it's way from the float chamber to the cylinders as a mist?
Thanks
Don

[John Hendricks]

Was the float "floating"?  I found that a popsicle stick was 5/64 thick so I made my own gauge.  Try putting the float in a pan of boiling water and see if bubbles rise to the surface.  be careful if it has gas inside-u would hate to have a kitchen explosion

[Don St Peter]

Thank you for all the good input. My starting problem I think is fuel related. Too much I suspect. I have removed the carb. and find fuel puddled in the engine just below the carb even though I was careful to not "flood" it in start attempts. The spark plugs are also "soaked" on inspection. I will be soaking the carb. in cleaner for a couple of days before attempting adjustments even though it appears fairly clean and the float needle is clean. The engine has probably 3 operating hours since a new carb kit etc.
My service manual shows a tool C-449 for measuring float distance of 5/64 in. from top of float chamber to float. Does anyone know how to measure or guage float position when one has no "tool". Couldn't float position too "low" cause part of my problem?
I'm concerned about the "timing" comments. How would one check the timing with engine unable to start?
Thanks in advance
Don

[David Pollock]

 If an engine has fuel, compression, spark  and is timed right, it has to start.  Assuming you have fuel compression and a good spark, and the engine ran OK the last time it was used, and now it won't start or makes only a half hearted attempt to .....  chances are, the timing chain has jumped a tooth.  This will retard the spark and valve timing about (don't quote me) 15 degrees of crankshaft rotation which, if you did get it to start, there would be so little power, you could not drive off.

I had this experience with a 55 Plymouth and although it would start, it had NO power. A timing light confirmed my diagnosis. The car had only 70 000 miles but that is about it in a timing chain's life, espescially if a lot of short  cold runs are being made. It takes several horsepower to turn a cold oil pump and that has to be transmitted through the chain.

[John Hendricks]

If u look in the float chamber and need to check the valve, don't drop the little pivot pin and half round spring that holds the valve in place

[John Hendricks]

I f U look down the throat of the carb and work the throttle linkage, do u see a squirt from sides of the transverse metal "bar" about half way down.?   A common problem in my 40 and 49 is a stuck intake valve in the float chamber--that little pointy piece that the float arm pushes on to close off flow when the chamber is full.  Mine sticks in the closed position when the vehicle sits for a while and the gas in the chamber evaporates and will not refill when I run the starter until I take the top off of the carb and free it up.  I don't know why it happens since everuthing is new.  A good starting fluid is WD 40 rather than ether based explosive spray can starting fluids.  Try pouring an ounce of gas down the carb followed by a good squirt of WD 40.  If the engine runs for a bit then stalls, look in the float chamber.

[Jim Benjaminson]

Are you sure its getting fuel?  If you have strong spark, that should be the only other source of problem.....I was thinking perhaps a bare wire inside the distributor but if you have strong spark that would rule that out (voice of experience on that one....)  What happens if you pour a little gas into the spark plug hole?  Does it fire then?

[Don St Peter]

I am beside myself on the starting problem with my 40 Ply P-9. I parked the car 2 weeks ago after a successful 100 mi trip. I have been unable to start it using all the choke, throttle tricks typically used. I have new fuel, good plugs, good looking dist. points and gap, good fuel flow to carb. and a strong ignition spark. I ocassionally get a strong start attempt from the old original engine, but it just won't start. I have ran down and recharged the battery many times now. I am very hesitant to pull or push it to get it started since it is only me and my wife ...... and you know the story there. I have not messed with the carbarator for fear of screwing it up. Could those of you that have been there and done that advise me.
Thank you in advance
Don