New guy with 1950 DeSoto - starting issue

[Wilf DeSoto]

Ok, so the accelerator pump is working fine, now how to get the excess fuel from the system and stopping it from sucking it in... Should I remove and clean the wettish spark plugs and push the car out and put it in the sun, hoping the intake will dry? I was also thinking about decoupling the fuel pump or blocking the line to it but sucking air or a vacuum is probably not a real good thing for the pump..? I want to stop the fuel flow to start with a clean slate, hoping it will just start as usual again...

[casper50]

remove all the plugs and turn it over a few times.  Most of the excess will come out.

[Wilf DeSoto]

I found out it was still completely flooded. I removed the carb and blew with a compressor through the spark plug holes whenever an inlet valve was opened at one of the three banks. I removed scary amounts of fuel this way.

When turning the engine by hand I noticed a whistling sound (like a potato flute) from the four last cylinders. Seems they are still flooded... I've been trying to start this car for 2 months without stepping on the gas (last week I even removed the spring from the pedal so I have WOT all the time) and still nothing has evaporated enough yet. And note the car had been standing still for months as well... So frustrating... Now I'm thinking how to remove excess fuel from the cylinders.

[Wilf DeSoto]

I've been at it for hours. The intake was completely dry. I cleaned and dried the new spark plugs. No damage on them. I have installed the carb back, empty. The intake was dry too. I had it stuck in WOT. Try to start and start and start. Not one puff. I am getting really frustrated here...

[desoto1939]

This might sound like a dumb question. Is the distributer seated all the way down into the block.  I had taken mine out to do a tuneup and then reinstalled the dizzy. It felt as if I had gotten the end of the dizzy shaft into the slot. I then tighten the lockdown bolt. Then tried to start the car but it would not fire up.  So I had a friend stnad but the ca to see if anything looked incorret. We then took the dizzy cap off and then crancked over the car. We noticed the rotor was not spinning it was staying inthe same position and not rotating.

 

I then loosend the lock nut and found out that I was not in to the slot inthe end of the oilpump. Moved the dizzy saft and then locked it down again. Sitll would not fire but the rotor was not spinning. So I knew then That I was 180 degrees out of sequence. pulled the dizzy again and rotated the shaft and got it into the proper positon and then fired up.

 

Check this this might be your problem.  Just a guess from my part.

 

Rich Hartung

Desoto1939@aol.com

[Dave72dt]

That much gas in the cylinders will wash the cyl walls  down and you will have very little compression.  Squirt some oil down each cyl, turn it over a few times, reinstall the plugs and try again.  You should probably change out the oil also. I'd bet on it being well diluted from the gas.  Chances are your float in the carb isn't floating anymore.  If it feels heavy or sloshes when shaken you will either need to repair it or replace it.  You will have to solve the flooding problem before expecting it to run well.

[Wilf DeSoto]

The dizzy turns, I've checked that a few times.

The float is okay. The last couple of tries the intake stayed dry. I thought the carb was flooding today because I put compressed air in to the spark plug hole and unbeknownst to me this blew back the gasoline after the hump on the intake back to the carb hump. After noticing that I removed the carb and emptied it et cetera and blew all three banks empty. When reinstalling the carb there was no more flooding in the intake.

How much oil should I try to put in the cylinders? It's hard to put it in the cylinders themselves of course. I've had it for today, after six hours of working on it. It's 4 PM now and I've got more to do... Maybe tomorrow... Somehow I don't believe the car will start tomorrow too....

[50desotocoupe]

Keep the faith!  We are pulling for you!  Did you by chance check the condensor? 

[Wilf DeSoto]

I replaced it, did not measured it. I will try the oiling tip next time.

[Lumpy]

Really, there should be some popping and banging, or some indication of combustion no matter how far the timing is off, if the ignition is good. I hope you have changed the condensor, as that is the first place I go if something becomes hard to start. Sometimes you will see a weak spark when the plug is out of the engine, but it won't spark under compression...which I completely do not understand but it happens.

 

If there is compression and spark, the engine will fire even without a carb on the engine, by just squirting a bit of gas or starting fluid into the intake. Either you don't have spark (even though you might see a weak spark with the plug out of the engine) or you don't have compression.

 

Verify that you have both good, strong spark, and good compression, and the engine will at least fire, pop or bang. A good coil, condenser, and points will give you good spark. Then verify you have compression, and it will at least fire...then sort out your timing. Again, you either don't have spark, compression, or both.

 

ken

[Darbone85737]

If you take spark plugs out of the head and ground them, when you turn the car over with the starter are they sparking ? 

[Lumpy]

He mentioned that he did see a weak spark...which does not mean they are sparking under compression. If there is compression.

 

k.

[Wilf DeSoto]

Yup, when I just lay the spark plugs on the engine they spark bluish white. Much whiter than before I changed all the distributor parts and plugs. There is compression (measured by thumb and very clear when starting with one spark plug out -> rapid acceleration of engine on that cylinder) but I did not measure it with any gauges. I will put some oil in it tomorrow. Somebody else told me I would best adjust the valve. I read this is a tedious chore so I hope it will start tomorrow another tip I read on the technical forum was checking the TDC on cylinder 6.

Edited May 19, 2014 by Wilf DeSoto

[Lumpy]

So...how much compression is there? Even with a valve stuck open, you might hear some air whooshing out the spark plug hole.

 

Do you have an attachment for your air hose to pressureize the cylinder? If you do, you can get each cylinder to TDC, then pressureize the cylinder, and see how much is leaking out.

 

If you have compression, spark, and fuel, it HAS to fire. Maybe not at the right time, if the timing is off, but it still has to.

 

There isn't a bunch of water in the gas tank is there? Water does not fire very well.

 

ken

[Jeff Balazs]

Wilf;

If you have a decent spark then you might try some spraying some starting fluid (ether) down the carb. If it is at all close that should get it to at least fire a bit. You should probably change the oil before running this engine as it has almost surely been diluted with gasoline.

 

Hope this helps, Jeff

[greg g]

Before you do any thing, double check your plug wires are correct as per the firing order and that number one is at tdc on compression stroke. Also assure that the distributor cap tower that number one spark plug is plugged into is aligned correctly to where the rotor is pointing. I was one off when I did my rebuild, once corrected it started so quickly it startled me.

[_shel_ny]

Have you static timed to confirm that the spark is there when it should be?

[Lumpy]

But, I still think it should pop, bang, or kick back if it has fuel, compression, and spark, no matter how you run the wires, or how the distributor is plugged into the block. My understanding is that the engine is giving no indication of any combustion, at all. ???

 

Yes, starting fluid. Just take the carb off the engine, (so you don't have any more fuel going down the cylinders) and spray a little bit in when cranking. If it does not fire, you really need to know how much compression you have. If you have compression, then it's a matter of why aren't the spark plugs sparking, whether they spark out of the engine or not. !! Again, air whooshing out of the spark plug holes does not mean you have compression, or enough. Not saying that you are saying that...but you did say you haven't done a compression test, but that it does have compression. ?????

 

Just a thought. I think a compression test should be priority #1. If there is no compression, it won't matter how much spark you have, or don't have, or what cylinder fires when. At this point, I don't think it matters if the plug wires are crossed, or if it is timed right, or even anywhere close to right.

 

I wore out an engine once, to the point that it did not have enough compression to start anymore. (unless you push-started it) It acted very much like it had no fuel or spark.

 

ken.

Edited May 20, 2014 by Lumpy

[Wilf DeSoto]

A friend of mine also thinks the compression is too small, the exhaust valves are probably stuck, burned of have too much play. I'll try to gap them correctly first. I have spend a lot of hours removing anti rust muck from the right wheel well. I cannot see it completely but it looks like I have to remove the part below the flat plane where the air inlet resides above. On the right are two bolts and on the rest are about eight screws right up to the end of the wheel well. Is this about right?

[James_Douglas]

Wilf,

 

Take an old spark plug. Cut off the insulator and the ground tip.  Drill out all the insulator.  Then tap and screw in an air chuck or weld an air chuck into it.

 

Then screw it into #1.  Make sure that your are at TDC on #1.  Listen for air out the exhaust and at the oil filler tube.  If your rings are leaking bad it will blow into the oil pan.  If you hear a lot of air in the exhaust then you know the #1 exhaust valve is open.  If you head it loud at the carb your know #1 intake is open.  Follow on down the firing order and check each hole.  If any of the valves are stuck open, this will find it.

 

Just in case the cars electrical system has an issue.  Hot Wire the car.  Run a wire from the battery directly to the coil and try and start it.  Just remember that you have to pull the wire to stop it.  The key will not kill it.

 

Good luck,  James

[Wilf DeSoto]

This weekend I changed the oil and tried to start the engine / clean it by pouring a bit of oil in the cylinders with a pipette and starting it with WOT and choke WO. I boost started it with a Snap-On garage help starter delivering an extra 60 Amps, this did give the starter engine a lot of oomph and speed but there was not the slightest rumble or bang, not even when I did close the choke and throttle again.

 

Furthermore I did a compression test with an old tool I don't know the correctness of. This was how I did the test:

- I removed all the spark plugs, plug wires and the coil wire

- Someone cranked the engine four times per measured cylinder
- I wrote down the following measurements (in chronological order):

Cylinder # - Pressure in pounds:

1 - 60

2 - 57

3 - 45

4 - 52

5 - 53

6 - 46

 

I then took a flexible pipette and poured a small amount of oil into the cylinder that I measured. I decided to measure backwards this time.
 

With oil:

6 - 42

5 - 53

4 - 54

3 - 50

2 - 56

1 - 50

 

The starter engine did lose more and more torque due to the battery not being full according to my battery charger. That's why I also reversed the second measurement to be sure it wasn't lower in the back of the engine due to loss of compression due to slower cranking.

So how should I interpret these values..?
 

(I'll edit in some photos later when my phone likes me enough to share them again)

[Don Coatney]

Your compression is very low.

 

These instructions might or might not help.

 

 

This chart gives an indication of expected compression on healthy engines.

 

[Wilf DeSoto]

Thanks, I really should do the leak test, but how do I go about doing this safely? I have a compressor but that thing makes about 6,5 bar. Wouldn't that be too much? How should I apply pressure in the leak test?

[Don Coatney]

6.5 bar is less than 100#. Healthy engine compression is in excess of 100#.

[Don Coatney]

Did you read posting #45 to this thread?