1946 Chrysler Windsor running issues

[Los_Control]

Something a real mechanic uses and I'm just testing the waters with it is a vacuum gauge. Here is a guide for using one.

 

Surprising what you can find out about your engine by putting a gauge on it.

The other thing is to run a compression check on the cylinders .... These engines have cast iron rings and will stick to the pistons and not seal properly.

The rings need to float and move loosely in the ring landings in order to expand to the cylinder bore and seal .... if stuck to the pistons the rings will not do their job properly.

Soaking them in marvel mystery oil will help loosen the rings and gain better compression.

Currently I have this issue and today I added a quart of ATF into the engine oil to help loosen the rings while the engine runs.

 

If you have vacuum leaks or are sucking air around the intake, carburetor, bad vacuum line leaking .... will cause it to pop through the carburetor.

 

If your timing chain is stretched, it will cause issues and easy to check ... remove distributor cap and rotate engine back and forth from crank pulley and watch how much movement in pulley before distributor rotor moves.

 

I'm sure much of this has been covered already .... compression check and then vacuum readings will help determine condition of engine .... all else are external and repaired without tearing into the engine.

 

[bacelaw]

It's frustrating to chase an issue like this, and easy to get pulled in 10 different directions.  I agree before you pull the cylinder head, a compression test and a leak down test will give you more information.  With good oil pressure, good compression, no leaky valves, you'll have ruled out any major trouble.  

[SeasonedNewbie]

I haven't yet gotten brave enough for a compression test. However, I did try the tests outlined in the vacuum gauge list. It passed the ring test, behaving exactly as outlined. I'm still inclined to believe it's late timing. I will get new plugs to see. I've also been trusting plug wires that came with the car. They look pretty recent but I know they can really turn things to crap.. though my experience has been they tend to work better cold, worse hot. 

[Los_Control]

An extra set of plugs is handy to have around.

I just went through a long process of diagnosing a run issue on my truck .... It is still not drive-able while torn apart for paint.

 

It did run really well then slowly over a year it just ran worse then eventually not at all and the distributor was shorting out.

I always planned to convert to electronic ignition so now was my time ... I collected parts and eventually a few days ago got the truck running on the new conversion. .... It did not run right and it had a terrible idle.

I messed with it for a day or so and then just yesterday I installed a used set of plugs I had, and now she runs like a dream.

A bad set of plugs can really wreck your day.

 

Running a points ignition system, I like to have a good running engine, then do a complete tune up on it and keep all the points, plugs, condenser, rotor, cap .... for known good working spares.

With today's quality control, can get bad non working parts right out of the box from the store. .... The parts you save are tested and you know they are good. .... They are worth their weight in gold when troubleshooting difficult issues.

 

I made a video yesterday after I got it running properly .... changing the plugs made it run better and then was able to set the timing and also adjusted the carburetor while the vacuum gauge was connected. ... It is good enough for me for a used engine  ...... The whole process even with bad plugs, I still had about 15psi vacuum that made me think late timing.

Just saying, bad plugs did not show up on the vacuum gauge.

 

[SeasonedNewbie]

We can rule plugs out. I got new, gapped and installed. It didn't hurt but no significant change. I ran til good and warm, took a drive and it still stumbles and carries on from acceleration. In 3rd it'll start developing a bit of power the way it normally does but then goes totally flat with no more power. Idle is ok, a bit unsteady at times. I suppose next is to test compression and see what's there. Vacuum is starting out at about 15 and slowly finds it's way to about 17 once it's warm. 

 

I did notice the exhaust heater flap sort of blows open on acceleration but closes again at idle. I fixed it open, no change. 

[SeasonedNewbie]

I meant to also add that it always starts right away. Even through all of this, it's still basically a bump from the starter and we're off. Maybe a couple cranks flat cold in 30 degree weather. But typically it's an immediate start. 

[SeasonedNewbie]

I might have this figured out. Here's my theory:

 

I wanted to double check my distributor work, so I pulled it again. Burned points. Brand new, new condenser, new cap, new plugs, new rotor, new coil. The points were set to the .020" recommended. 

 

Remember, this car got switched to 12 volts at some point. And it's charging system was non-operative. The coil it had when I got it was 6 volt and eventually was cooked. Then, I got a 12 volt coil. It ran, but poorly. So I read about coils and that is a confusing topic with lots of disagreement. But, it ran better with the 6 volt coil, so there I went. It ran great, no trouble. 

 

Then ... I fixed the charging system. That was also not too long before there was a problem. I don't know how long, perhaps a couple weeks?  The battery charges and it's now supplying the full voltage to the coil. Before, who knows how much it was actually getting. Is it possible that now with the system charging working that it's overwhelming a coil designed for less voltage? The only flaw here is that it took weeks to ruin the last points, mere minutes to ruin these. 

[Los_Control]

So I went to the beginning and watched the video .... brought out a couple of questions.

Curious about the 12V conversion and if you have 12V going to the points?

Mopar you would use a ballast resistor to drop the voltage to 6v going to the points ....there are other ways.

 

One thing I was thinking about that is pretty rare but a coil going bad.

A coil being run on a positive ground system then later reversed and run on a negative ground has caused weird issues.

Coil gets use to current flowing one way and then when the flow is reversed, it can cause strange ignition issues like you have .... certain rpm it starts to cut out. .... typically found if you grab a old coil off the shelf and run it differently then it was use to being ran. .... You have a new coil ... should not be a issue unless it is faulty and going bad.

Then you said something about the battery being connected backwards? .... or just the amp gauge is backwards?

 

That brings more questions. I'm going to assume you are 12V negative ground, you just never reversed the wires on the amp gauge ..... How many amps is your alternator putting out? .... typical modern alternator puts out more amps then the original gauge can handle. Eventually burning out the gauge.

You can use the gauge but you introduce alternator charging after the amp gauge .... Now gauge is just reading battery amps and not charging volts. .... some wiring needs to be done there when converting to 12V.

[Los_Control]

Dropping the voltage down to 6V saves the points, straight 12V will burn them out early.

Let me add a image of typical mopar system.

There are 2 wires from ignition switch going to the ballast resistor.

One wire from the on position that supplies power to the ignition through the ballast resistor.

A 2nd wire is attached to the start position and connected after the ballast resistor.

 

What happens when you start the car you bypass the resistor and shoot 12V to the points for easy starting.

When you release the key after starting and is on the run position, it is sending 6V to the coil and that is all your points need to run off of.

 

Edited Saturday at 05:22 PM by Los_Control

[SeasonedNewbie]

I didnt do the conversion to 12 volt negative, it was that way when I got it. For one thing and another, flipping it back to positive ground 6 just hasn't been an option yet. 

 

But I've accounted for the reversed polarity each step of everything I've done. I just haven't gotten behind the dash to change the amp meter. It's using its original generator to charge, so I don't think the amp meter is getting hit too badly. 

 

There's nothing between the battery and the coil, so whatever is going in there is going out the other side. 

[Sam Buchanan]

50 minutes ago, Los_Control said:

 

 

That brings more questions. I'm going to assume you are 12V negative ground, you just never reversed the wires on the amp gauge ..... How many amps is your alternator putting out? .... typical modern alternator puts out more amps then the original gauge can handle. Eventually burning out the gauge.

You can use the gauge but you introduce alternator charging after the amp gauge .... Now gauge is just reading battery amps and not charging volts. .... some wiring needs to be done there when converting to 12V.

 

Some clarification may be needed here. An alternator will only output the amps needed for the load connected to it. Yes, an alternator may be capable of outputting 60a, but unless there is a 60a deficit in the vehicle system it won't deliverer 60a. The highest demand would be for a severely depleted battery, maybe one that has been allowed to *completely* discharge. But a battery will not need such a heavy charge just to replace capacity that was used during normal use so the alternator, even though rated for high output, will not deliver anywhere near its rated output. So the amp gauge continues to live a happy life.

 

But it is true the amp gauge can be reconfigured as a load meter instead of the original design. I unintentionally kinda did this when adding headlight relays that feed directly off the battery. Since headlight current is no longer passing through the amp gauge (and original headlight switch and wiring...this is a good thing....) it shows amps being delivered by the alternator that are being absorbed by the headlights in addition to the usual load from the rest of the car. So the gauge is now a hybrid which in real practice is a non-issue (it functions normally when the headlights are off), just a bit different from the original setup. This is why many consider a voltmeter to be more useful (and less stressful on the system) than an ammeter.

Edited Saturday at 05:52 PM by Sam Buchanan

[SeasonedNewbie]

1 hour ago, Los_Control said:

Dropping the voltage down to 6V saves the points, straight 12V will burn them out early.

Let me add a image of typical mopar system.

There are 2 wires from ignition switch going to the ballast resistor.

One wire from the on position that supplies power to the ignition through the ballast resistor.

A 2nd wire is attached to the start position and connected after the ballast resistor.

 

What happens when you start the car you bypass the resistor and shoot 12V to the points for easy starting.

When you release the key after starting and is on the run position, it is sending 6V to the coil and that is all your points need to run off of.

 

 

If there's a ballast resistor between the key and the coil, I haven't seen it. There's 2 wires I believe going into the positive side of the coil (remember it's all backwards) and one wire from the negative headed out to the distributor. Other than that, it's pretty much what it came with. 

Edited Saturday at 06:17 PM by SeasonedNewbie

[Los_Control]

These things are just fresh in my mind because have just gone through it myself and still need to build the wiring harness for my truck .... The ballast resistor way is simple and all I know about ..... is possible the resistor is under the dash .... just not likely.

Again there are other ways .... Ford and GM never used ballast resistors and work fine .... I just do not know what components were used and how they were connected. The ballast resistor is easy.

 

I'm not sure what you mean by using original generator ... do you mean a newer 12V generator was swapped in?

Or possibly they added a 12V voltage regulator and asking the 6V generator to produce more?

I have seen that done on stripped down Hot Rods ... it is possible. .... Not practical.

Something has a funny smell here

 

I'm just thinking that possibly things were not done correctly ... the original points/condenser was of good quality and lasted awhile before they failed and you changed them .... today's quality of replacement parts might last you a couple days or a week? .... Probably need to investigate how the ignition system is wired in and be sure it is correct.

 

Mark me as more confused because the more I learn

First I would figure out what is really going on with the 12V conversion .... wont help the run issue.

Then with that information could address how to wire the ignition system.

Burnt points and such are going to be the norm until the underlying issues are corrected.

 

Or swap to electronic ignition and move on ... it uses straight 12V  

[SeasonedNewbie]

I don't know that much "converting" was actually done. There was a voltage regulator on it of unknown type, one of the little resistors had burned through on the bottom. I replaced it with a 12 volt unit. So it's using the factory generator wired through that. My understanding is that the generator really doesn't care. The battery stays up and I haven't had any issues from that. Except possibly this. 

 

It appears to me that the ignition is wired properly. 

[Sam Buchanan]

Here is a very simple way to address the "ballast resistor" issue, this is the coil on my TR6:

 

[SeasonedNewbie]

16 minutes ago, Sam Buchanan said:

Here is a very simple way to address the "ballast resistor" issue, this is the coil on my TR6:

 

And that comes back to my original thought, a 12 volt battery that was constantly running low not putting out enough to adequately run that. But now, will it work better that it does charge at speed. 

[Los_Control]

1 hour ago, SeasonedNewbie said:

My understanding is that the generator really doesn't care. The battery stays up and I haven't had any issues from that.

My understanding where I saw it was done .... It was frowned on by the mechanic/owner ... same time it was on a model A roadster that had no radio, heater, a single windshield wiper .... was never going to be driven in a daily type of situation .... he thought he could get away with it.

 

Try driving at night with headlights in the rain with wipers and the heater going along with the radio .... I have doubts the 6V generator could keep up ..... nothing I would depend on ..... This is when your existing amp gauge would fail and leave you walking ... wired the way it is .... if your generator could produce enough.

still it is not your run issue I do not think .... just a future @SeasonedNewbie issue.

 

I also want to point out, @Sam Buchanan is way more knowledgeable on electrical then I am .... I trust his word over mine.

If you want to shim a oil pump with a copper penny on a 2 seater cesna airplane I can help 

 

As sam's photo shows ... I used a different coil .... there is a difference.

You say your ignition is wired right .... which coil are you using? .... not all coils are the same and need to specify when you purchase.

 

You have a burnt set of points .... lets figure out why.

[SeasonedNewbie]

Like with so many things, there are numerous opinions on the subject. I don't intend to use the car as a daily driver, so it's ok when it's not in the mood to go. But personally it bugs me. It seems to charge though when I've got the heat and the lights, just not at idle. It's usually hanging right at zero or just below (again, backwards) at speed. 

 

I agree, burnt points are the problem to solve. I definitely don't have the right coil, I'm going to get a 12 volt internally resisted one and yet some more points. I will see if I can trace wires and see if I can verify everyone is wired properly. 

 

Incidentally, I was working on my pilot license til I couldnt get my medical certificate. I admired those little Cessnas, I spent a lot of time in one. 

 

 

 

 

[Los_Control]

Just a heads up, there are still several NOS ignition tune up kits available on ebay .... need your distributor serial number to be sure and order the right parts.

Just a opinion but when ordering new, I try to find "Standard" brand parts ..... made in Mexico but possibly better then China, they do look better. .... The rub block on China points wear quickly, Standard brand looks more robust.

 

I would be curious to see what a multi meter shows your battery is charging at with accessories turned on .... I would hope for 14V .... if it was down around 13 I would predict the battery is not getting fully charged .... whatever, not my problem.

 

I poke fun at sam because he is a pilot, I think he has his own plane ... not sure.

As a carpenter my employer and his buddy was talking about flying down to Mexico for a 2 week hunting trip.

They were discussing who's plane they would take .... they both had early 1960's cesna's.

One was complaining that they could take his, but the oil pressure was low on it. But it would be OK.

 

The other said he did have the same issue, but he took apart the oil pump and shimmed the spring with a Penney so it produces more psi. .... So it was settled, they were taking Jim's plane because he shimmed the pump and had more oil pressure.

 

OMG, can we replace the rod bearings first before I fly with you guys?  🤣🤣🤣

It all worked out fine and the wives fully fumigated them upon return of their 2 week vacation.

[SeasonedNewbie]

I definitely want to solve the problem before I trash a NOS set of points. 

 

It probably isn't an ideal charging rate. I didn't put much trust in it either but putting a battery charger to it, it clicked right to full. I do want to go back to 6 volt positive ground but I really should put all new wiring in. I have yet to find a good set of instructions for how to get the dashboard out. That is my main catch there. 

 

I remember once pulling the dipstick and seeing shiny flakes, they pulled that motor. My CFI was fortunately pretty safe when it came to all that. I did however fly with a guy a few times that no doubt put his change in the motor... I remember going in his WWII bi-plane and really wondering what level of work it had seen. No problems but stalls in an open cockpit was enough for me. 

[Los_Control]

4 minutes ago, SeasonedNewbie said:

I do want to go back to 6 volt positive ground but I really should put all new wiring in. I have yet to find a good set of instructions for how to get the dashboard out. That is my main catch there. 

 

Thats a decision only you can make .... 6V positive ground is fine .... if thats what you want.

Just need to get the correct voltage regulator and connect battery correctly and you will be further ahead then you are now.

 

Only a Desoto owner can help you with pulling the dash .... I doubt it comes out myself.

I assume you have to pull the seat and crawl under it from there.

 

My truck had a seat base that was welded to the floor .... then the seats bolted to the base .... no help in working space removing the seats. imagine the cars are same way.

 

I did grind and cut out the welds on the seat base and now have a flat floor I can lay on.

I modified the seat base and welded in supports for lap seat belts to anchor to and then it is bolted down to the floor with 16 3/8" grade 5 bolts. ... Instead of being welded to the floor .... pita but I can remove it and have easy access under the dash.

Nobody ever said it was easy, nobody ever thought 75 years later we would be talking about how to maintain these cars.

 

[SeasonedNewbie]

A DeSoto guy did share some pictures with me but only after the dash was away. There are a lot of brackets and braces, the vent, the radio support, the wipers. I think some of the hardware hides behind the windshield trim. I believe it does come out though, and I know the instrument cluster will. How, I couldn't tell you. And getting it all back, oof. 

 

Fortunately the Chrysler came with an adjustable front seat and I believe it comes out. I know the floor pan will also unbolt and lift away. I could make a better arrangement for myself in there. 

 

 

[SeasonedNewbie]

So, I couldn't stand it... I got a 12 volt internal resistor coil. I also cleaned up the points to give me a chance to at least start the car. Frankly I was expecting it to be the same as before but I was pleasantly surprised. The idle was nice and smooth, I checked the time by the vacuum gauge. Cold, I was hovering just above 15. And it is very cold outside, so I let it warm a bit and tried a drive. Back to normal, plenty of power, no hesitation. After that I had vacuum closer to 20. Obviously it needs good points in it but now I feel more confident that it's not going to burn up the next set. And it seems to minimize the worry about something internal. 

 

We're about to get an extreme winter storm here but I need to now change the oil since I've had lots of starting and stopping mixed with crappy combustion. For today, I think we have the answer.