New guy with 1950 DeSoto - starting issue

[Wilf DeSoto]

Hello guys and gals,

 

I'm Wilfred from The Netherlands, a small country across the ocean. I've had my DeSoto for three years after falling in love with in in Sweden. I drove it home and have driven about 600 miles with it every year. I've always been a Mopar driver; my first car was an M880 (Dodge W200 from the army), I've had a Plymouth Satellite Custom station wagon from 1971 and a Plymouth Valiant V100 2dr post car. I've never been without a Mopar, although I just bought my dream car (not a Mopar I'm afraid to say).

 

I'm thinking of selling my DeSoto because I bought the other car (not sure of selling though; I'd rather not) but anyway, it won't start up right now, so I cannot enjoy driving it too. And when I cannot drive and have fun with it selling is all the more an option, so please help me with my starting issue so I can make the sanest choice

 

So here's the problem:

 

The starter turns, there is spark, there is fuel but not a single ignition. I changed the spark plugs (gapped them first) but to no avail. I've refurbished the carburetor but to no avail. I recently bought a tune up kit from Andy Bernbaum and am now refurbishing the distributor. It is in pieces on my desk as I type. It's the IAT-4004 as found on the later 1950 DeSoto's.

Now for some questions:

The workshop manual says I have to lubricate some parts with medium oil, some with light oil and some with grease. Can I use:

 

- 20W50 classic car oil for the medium one? Single grade oils are hard to come by here, I had a hard time finding 10W for the tranny. 
- sowing machine / air tool oil for the light oil?
- EP2 grease for the grease? As with the single grade, distributor grease is really hard to come by (everything here is modern and pointless *no pun intended*).

Furthermore: I could not find with which lubrication I should lubricate the weights and springs and with which I should lubricate the contacts between the base plate and the breaker plate.

Those are my basic questions for now… I hope my introduction and questions are not too bad, if you want to know more about me just ask.

Thank you!

[desoto1939]

did you change any of the wires for the spaqrkplugs, are they in the correct order. How did you verify spark? Did you take a plug out and have it connected to the wire and then turn over the ngine to see is the plug is sparking.  Are oyu getting fuel into the carb  did you chnage the condensor what is the gap that you are using. If I remember correctly it shoul de 20 but bring it back allitle to 18 might be open too far.

 

If you have spark and fuel it shoudl fire up unles you are out of the correct timing sequence.

 

Rich HArtung

Desoto1939@aol.com

[Ulu]

Wilf,

 

The oils you mention will be fine. Those parts aren't to critical of the lube as long as there is some so things don't rust.

 

But the grease isn't the best choice. New points used to come with a tiny bubble of lube. It's been 20+ years since I bought any points though.

 

I'd check an electronics shop for switch grease. It mainly has to stick where you put it when hot or cold, and it has to prevent corrosion.

 

It's lubrication duties are modest.

 

Anyhow, I'd test that coil, by running it on another car if possible, or swapping a running one onto your Desoto.

Edited May 14, 2014 by Ulu

[Wilf DeSoto]

Hi Rich,

 

thank you for your reaction: The wires are quite new and are still in good condition. They are in the correct order. I verified spark by putting sparks on the engine and turning the engine. I say sparks, they were nice and blue but very thin. The distributor cap had a lot of wear: the connector in the middle is almost completely worn out and the points have black pitting. 

 

I have not changed anything in the distributor yet. I got fuel in the carb allright; after trying to start and start (and pump) the car got flooded. I will gap the new stuff at the right gap (I believe it was 0.20 but I will check in the workshop manual when gapping).

 

It has been running the last three years, I've put it in hibernation last winter, since then it will not start. Last year the car would start worse and worse (especially when hot) and stalled more and more (especially when hot and in traffic jams). I thought this was due to vapor lock but I think it is vapor lock AND bad ignition (why else would it deteriorate).

 

 

 

Hi Ulu,

thanks for your reply. I will search for another grease and use the rest. I could test the coil in my new car (it's a '49 Buick). I have another coil that I got from a running car from someone, that one has 3.77 kOhm on the plus to high voltage. I read it should be more like 8 to 11 kOhm (I found that on a site somewhere, not sure if that is 100% correct).

Great answers, very fast, thanks a lot guys!

Edited May 14, 2014 by Wilf DeSoto

[jeffsunzeri]

After periods of inactivity, these flatheads will experience valves stuck in the open position. This will prevent starting. Check your compression on each cylinder to be sure.

[desoto1939]

Since the cap has a lot of wear I would also replace the cap, points and rotor and condenser also check all the little wires inside the dizzy.  Since you state things are worn out then replace these items should be replaced because they are important in get the spark also.

 

Rich HArtung

[Wilf DeSoto]

That's exactly what I am doing. I got the K-103 tune up kit for a IAT-4004 from Andy Bernbaum. I must say what a fast service and knowledgeable people, I ordered end of last week and got it beginning this one, that's fast for international shipping (sometimes it takes weeks)! And every part looks exactly the same as what was in the distributor. I first ordered parts at Rockauto and not one part was the same as mine, the cap was for an eight cilinder and the shipping was multiple times the cost of the parts...

Anyway, there is one wire that I really need replaced: the wire from the points to the coil. The insulation was broken and it was shortening against the housing. Probably not a good thing since it is insulated from the housing! Problem is that that particular wire is an integral part of the hold down for the contact point spring and is crimped in such a way that replacing the wire or insulation only is impossible. I didn't notice the breakage when the dizzy was in the car because it was fouled and the breakage was hidden from view behind the contact breaker spring and housing.

[Wilf DeSoto]

Jeff, good one to check too! It felt I had ample compression when turning the engine by hand for TDC (I had to help with the starter first to get it primed a bit) but I have noticed in the three years that I got the car that after a long period (a few months) starting took a while and it mostly suddenly would start with a bluish black cloud right after the first start, then run fine. I must say I know the exhaust valves need some attention but the engine runs quite good anyway (when driving for longer periods (say an hour), it will chug a little, randomly with random intervals, when idling).

[Wilf DeSoto]

I thought I'd share a video of the car:

This was last year, when it ran when parked

[50desotocoupe]

That my friend is a great looking Desoto!!!!!!  I think the stance is just about perfect!

 

Matt

[Don Coatney]

A simple compression check can be done by disconnecting the coil wire. Crank the engine with the starter motor and listen for a cranking speed change. Watch this video. About 4 minutes into this video you can hear the sound I am talking about.

 

http://www.youtube.com/watch?v=fWlAVrCPnfE

[Wilf DeSoto]

Thanks, I also learned that clowns stink. Never knew that.

Today I put in all the new distributor components, well gapped (.020") and greased and oiled, some new wires (old ones missed parts of the insulation) and away I went. Guess what: still absolutely nothing. I went and checked cylinder one, removed the spark plug, hand turned the engine, watching the valve and rotor, saw the inlet open when the rotor was at about 4 o clock, closing at about 5 o clock (all estimates), points opening when rotor was at 7 o clock.

I haven't double checked for spark this time yet (due to lack of time) and haven't measured compression (have to lend a gauge). I did notice that someone once painted a white stripe on the main pulley, the points opened later than the stripe. Of course I don't know how correct that stripe is but I changed the timing of the distributor to exactly that white point (being 0 degrees if that stripe is correct). I tried to start again after that but the battery was quite drained by then so there was no juice left by then.

Maybe I should also check the voltage from the battery, maybe the battery is the culprit. Is that possible? Remember: I have no sign of combustion what so ever. It's like cranking without the coil wire attached. And I know I have fuel and spark...

[busycoupe]

It could be the battery. Earlier you said that you had spark but that it was "thin". Can you jump start the engine? You can use a 12v battery to test it if a 6v is not available. .. Also check your battery cable connections.

[Wilf DeSoto]

I'd rather not try with a 12v battery, I find that a bit scary. The connections are good, big cables, the same as modern power welding machines use. The starter engine turns what I think quite normal. The only thing is that the battery seems to lose its power after about 30 minutes of cranking (do not worry; I don't crank more than 10 seconds at the time and I take some breaks for about 1 to 2 minutes to cool everything off - the 30 minutes includes the breaks).

[_shel_ny]

When you borrow a compression gauge, be sure that it does not extend in to far. Some threaded one go in to far, and will be struck by the valve when turning the engine over.

[Wilf DeSoto]

Good point, I already noticed the valve coming very high up, nearly missing the spark plug. The valve looks quite white by the way.

[_shel_ny]

 All the compression, spark, and fuel in the world will not help if they are not all there at the right time.

 

This may be helpful:

The light will tell you.

 

 

http://p15-d24.com/page/p15d24/tech/tech_tips.html#static

[Wilf DeSoto]

Thanks, I don't have any timing indication on my main pulley as I said, only a dab of white paint I think is on the TDC place. I had to rotate the distributor housing completely counterclockwise (as far as the timing screw could go actually) as to open the gap just at the same time as the white dab of paint is on the marker. If I am correct there is still another screw on the back of the housing to advance it even more. More advance may help to get it started, I presume? Better a bit too early than too late in this case. Then I know if it's the timing that's the problem.

[desoto1939]

Ok here is your timeing information: for Desoto's from 1949-53 six

 

Spark plug gap: .035

Breaker gap.020

cam ang;e 35-38

Fire order 1 5 3 6 2 4

Timing mark  Second line BEFORE 0 mark on the vibration dampener or TDC is 0

Plugs AL-AR8

 

On the vibration dampener then will be a flat spot.  Clean off and grease or grime on the flat spot then Take some sand paper to get down to bare metal.

 

Shine a good work light on the flat spot you will see tiny lines cut into the dampener.  You might see a large line in the middle with a zero  and then smaller shorter lines before and after the 0 (TDC)  You can then put a fine white line using a fine paintbrush to indicate 2  degress before TDC.  Now also mark the tip of the pointer on the crankcase cover also in white.

 

Now your timing light will pickup both marks when the light flashes.

 

When you took the dizzy out of the block did you mark the block to indicate the same exact position to put back into the same position.  You might be out by 180 degrees. You should have a slot or keyway at the end of the dizzy shaft. So either you are on mark or could be off mark by 180 degrees.  I think number 1 on the cap and the rotor should be around the 7 oclcok position when the correct firing order is setup.

 

Rich Hartung

Edited May 15, 2014 by desoto1939

[Wilf DeSoto]

I gapped the spark plugs and breakers, I have no dwell angle measure tool. Firing order is the same. The crankshaft pulley has a flat spot but that's not even close to the first firing order, as said before I guess the white paint dab is TDC. There are more white lines on the pulley, I guess 180 degrees on the other side, faulty placed. I made pictures and films before removing stuff so I know for sure everything is in the same place as it was when the car ran.

[_shel_ny]

Should be seeing something like this.

[Wilf DeSoto]

I looked for something like that but couldn't find it. I have turned the engine by hand with a light present multiple times.

[Don Coatney]

Not all dampers were stamped the same.

 

[Wilf DeSoto]

This weekend I tried a few things. There is compression (removed a plug and engine speeded up while cranking), put my thumb on the hole while turning the engine by hand to feel when I got to TDC. The timing is indeed correct with the white paint.

Anyway, today I noticed the intake was wet again… Spark plugs wet… So I think there is something wrong with the carb. I did refurbish it as good as I could (I didn't have any refurbish kit because I couldn't find one). I tried cranking with WOT and idle screw completely closed (it was 1,5 turns open previously) but to no avail… Still flooded. I pumped the excess fuel out of the intake every time.

So what to do now? There is something wrong with the carb, I don't know what. I have cleaned it extensively and put everything back to factory settings, except I read that the modern fuels have more problems with vapour lock so I bended the plunger a bit lower again (it was much lower before refurbishing, so I thought that maybe that was the problem - I guess the previous owners did that on purpose because it was flooding..?).

 

I also noticed there is a substantial amount of fuel squirting when pushing the throttle down fast. Maybe it's normal but it looked like a lot:

Edited May 18, 2014 by Wilf DeSoto

[Niel Hoback]

  Looks good to me.