Carburetor Circuits

[Captain Neon]

Maybe I'm looking in the wrong place?  I don't see anything like that on Langdon's website.

[Sniper]

22 minutes ago, Captain Neon said:

So where does one pick up a phenolic spacer for a 23" L6?

 

 I made one for a unique application.

 

http://www.yourolddad.com/tbi-adapters

[greg g]

Call them.

[keithb7]

Still chasing the miss. Better with coil wire addressed. Still not done. 
 

A couple more things found.

 

What do you folks make of this?

Oil film inside my distributor cap. The cap does have a vent hole. On the side. Right under where the cap retainer clip sits. The oil film seems to concentrate near this vent hole. Somehow sucking in oil mist near my crankcase vent tube? Is this even possible? The rest if the distributor seems good. Breaker plate and points, wires etc appear clean and oil free. 

 

 

[keithb7]

Regarding the Distributor driveshaft tang. I’m feeling excessive shaft rotational play when I turn the rotor, when mounted in place in the engine. 
 

Looking at the tang where it sits into the oil pump. I don’t like what I see. Wear. Comparing it to a spare distributor shaft, my ‘38 is thinner. I think I’ll need to address this. Its not great. I better go shopping. 
 

Comparison and measurements shown. I wonder what the oil pump female end looks like. Hmmm. 
 

 

[Sniper]

Don't forget that the rotor is not solidly connected to the distributor drive shaft.  The advance mechanisms will move the rotor.

 

That oil is problematic though.

[keithb7]

1 step at a time. Controlled adjustments and tweaks. Reassembly and testing after each step. This allowed me to feel the improvements, or not.

 

The engine miss has finally been alleviated. I took the distributor out again today. Took the breaker plate out removed and cleaned everything up. Must have taken .010” or more off the points to get them closer to closing square. I set the gap at .018”, I  rechecked every connection on the breaker plate. Inspected every little thing. Cleaned up the light oil under the distributor cap. Not sure what that’s all about.  Will keep an eye on it.  
 

Test drove it and experienced excellent results. Tonight is the best its ran since I took ownership. Between the carb air leak, incorrect float level, incorrect fuel pump, internal carb issues addressed, fuel regulator removed, timing set again and again trying different settings, air fuel mixture screw adjusted, dwell tweaked, distributor parts & under cap cleaned, coil wire replaced, she’s feeling really good. 
 

I still plan to perform a valve set on this coming Sat morning. I’ll keep burning MMO indefinitely and monitor cylinder #2 psi.
 

Finally, maybe I’ll sleep past 5AM in the morning. Lol. 

 

New points are on order. Have been for some time. I'm on the e-bay never-ever waiting plan.

Edited June 17, 2021 by keithb7

[Sniper]

10 minutes ago, keithb7 said:

Finally, maybe I’ll sleep past 5AM in the morning

I know that feeling.

[keithb7]

On 5/30/2021 at 5:31 PM, harmony said:

Re: green arrow.  Quite right, no spring there.  The ball should be 3/16" dia.  Sounds like whoever was into that carb wasn't sure about things so you might want to check the dia. of the ball at the bottom of the accelerator pump chamber under that clip.  That one should be 5/32" dia.  They might have switched them by mistake.

Looky here what I found today! I went back into carb carb today. The two balls are the same size.  You nailed it @harmony. This won’t do. I have two correct sized balls in the carb kit I recently purchased. They are going in now.

 Thank you harmony. It looks good on you!

Edited June 26, 2021 by keithb7

[Los_Control]

OOOh bad memories ... While learning some things I rebuilt my carb .... I messed up and mixed the 2 different sized balls.

Catching my mistake, I actually had to use a map gas torch to heat up the carb body to get the small ball to release from the big hole.

 

Just saying, when I mixed the 2 different sized balls up. I needed heat to expand the carb body to release the little ball.

Then chase it across the floor when it did release. Then re-install in correct hole.

 

Just saying if your carb is working, it may not be the actual bearings that drop in and fit the hole. I suspect the carb would not work at all if the balls are swapped.

Just what I found.

[keithb7]

I got the balls out. I used compressed air and a round magnet. The smaller one down under the circlip was very stubborn. Compressed air with a rubber nozzle tip, pointed down the inlet port, at the bottom of the main bowl, shot it up. The round magnet was down the accelerator pump barrel, waiting for its launch. 

 

I was not happy with the raw fuel stream from the accelerator pump. I replaced it with a new one. I spent extra time with aerosol carb cleaner spraying orifices everywhere. Little red straw did very well directing it exactly into every little port. Carb cleaner came out every one. Followed by compressed air. Looking great in there and the raw fuel shot from the accel pump looks perfect. Re-checked float. Bang on 5/64 . Anxious to drive it again. Will soon as the temps drop below 90. Maybe this evening.

Edited June 26, 2021 by keithb7

[harmony]

4 hours ago, keithb7 said:

Looky here what I found today! I went back into carb carb today. The two balls are the same size.  You nailed it @harmony. This won’t do. I have two correct sized balls in the carb kit I recently purchased. They are going in now.

 Thank you harmony. It looks good on you!

I'm glad you discovered the same size balls after I mentioned that it was a possibility.  It feels good to pass on advise that can catch an error.  You, along with many of the Mopar enthusiasts here have helped me immensely over the last couple years since I bought my 48 Chrysler.  I don't know if this was a pay back, or a pay forward.  I just like that I could contribute constructively to an issue you were having.  It feels good to give after all the receiving that I have been getting.

[DonaldSmith]

All this talk about balls can get the little boys giggling.  There must be a double meaning in there somewhere. 

Also, when talking about my trailer hitch, and I tell the guys that I have two balls, and one is bigger than the other, they look at me funny.   And I ask the electrician if he has wire nuts?  What's with this language?  Andy Dodge, move over.  My turn to sit in the corner.  And I just came from church.

[Plymouthy Adams]

your bang on 5/64 float could end up with you banging your head as to percolation later especially if you are going to use pump fuel of ethanol blend.....suggest lowering the float level a tad.

[keithb7]

1 hour ago, Plymouthy Adams said:

your bang on 5/64 float could end up with you banging your head as to percolation later especially if you are going to use pump fuel of ethanol blend.....suggest lowering the float level a tad.

 

Ok thanks Plymouthy I will consider that.I am running 94 octance, non-ethanol fuel only. Adding a little Marvel Mystery Oil too. In an attempt to free up a stuck ring.

 

I got up with the birds this morning. Before sunrise, I headed out for a test drive. It was nice and cool. No traffic. The car ran the best ever today. No surging. No hesitation. Smooth, even power delivery. Yet I heard & felt just a slight mis-fire. I got to thinking it over. I'd addressed almost all I could with the ignition and fuel system. I grabbed the multi-tool I keep in the glove box. It folds out make to a set of pliers. I re-tensioned all the fastener clips on the end of each spark plug wire. They were progressively getting  looser from all the removal and installation times over the past 2 months. That did it. I will buy new wires I think, just to be "fer-sure, fer-sure".

 

I think based on seat of the pants feel and experience, I am close to having everything dialed in just right. I have no scope tune up machine, nor fancy sniffer equipment but it feels great. Its been a heck of a fun, educational experience over the past 2 months getting this all sorted.

Edited June 27, 2021 by keithb7

[TodFitch]

9 minutes ago, keithb7 said:

. . . I am running 94 octance, non-ethanol fuel only. . .

I understand the non-ethanol  but I don’t understand the 94 octane. . . Have you modified the engine’s compression ratio enough to need that? Or is non-ethanol not available in 87 (or lower) octane in your area.

[keithb7]

Just now, TodFitch said:

I understand the non-ethanol  but I don’t understand the 94 octane. . . Have you modified the engine’s compression ratio enough to need that? Or is non-ethanol not available in 87 (or lower) octane in your area.

94 here in Canada is the only non-ethanol fuel we can buy. There is no other option if you want non-ethanol.

 

[Plymouthy Adams]

as for the non-ethanol...yeah I would prefer it but my cars are also built to run on ethanol..it is still a better blend that what was at the pump in 1952..the only time I spare the change for non-ethanol is my small engines, chainsaws, weedeater and blower etc.  My mower rarely will set as if I am not mowing grass, in winter I am mulching leaves....never has time to go stale.

[chrysler1941]

At least you can buy non ethanol. We don't have that option.

We have option of E5 or E10 meaning 5 or 10% bioethanol

E5 Ethanol is only available as 100 octane. So timing has to adjusted. 

Edited June 27, 2021 by chrysler1941

[sidevalvepete]

A really good thread Keith. Will be very helpful to all with the largely standard fuel system in these old Mopars. Glad you have got to the finish line on this one. No doubt the next race is about to start somewhere soon and I look forward to that journey too. Thanks for sharing all of this ?

[keithb7]

Thanks @sidevalvepete.

 

Earlier in this thread I did mention the task of performing a valve set. I did complete that work last Saturday. There were no tight valves. Most all were 0.002 to 0.0035 wider than spec. Could be the previous owner set them wider for a long hi-way trip. I re-set them all cold, hot spec plus 0.002". The valve set seemed to offer a some torque improvement. Glad I did it. 

 

I also forgot to mention that I yanked out the earlier 35, 36 & early '38 style breaker plate and points. The points were hard to find. I have a pair now. But it took a month to get them. I went with the later '38 and up style of points and breaker plate. I have several spare sets of these later style points. This did indeed offer up improved engine performance too.  The old style points had been over tightened at some point. The lock down nut threads were stripped.I found the dwell would not hold where I set it at, 38 degrees. Digging in further I found the bad points.

 

I found quite a few things to get this car dialed in. I gained some great experience along the way.

In summary:

 

-Bad coil wire at internal rear of coil. Exposed wire strands possibly going to ground intermittently.

-A non-stock spring inserted above check ball, under set screw for accelerator pump circuit

-Bad points anchor bolt. Stripped threads. Would not lock down and hold the set gap. 

-Incorrect sized BB's in the carb valves for intake and outlet of accelerator pump. Found both BB's same size.

-Valve lash wider than spec

-Oil mist inside distributor cap

-Air leak at carb base adaptor place. Gasket shriveled up and shrunk. 

-Accelerator pump leather cup hard and stiff. Could not maintain steady flow of raw fuel stream

-Adjusted float level to spec

-Re-tensioned spark plug wire caps that anchor to spark plug.  Getting loose.

- Added carb base plate heat shield

-Added heat shield at front bottom of exh manifold to assist keeping fuel pump cool

-Removed incorrect fuel pump and pressure regulator

-Installed stock type mechanical fuel pump, without built-in air pump

 

Every step that was addressed seem to add some improvement. I will continue to add Marvel Mystery Oil to my fuel tank. In an attempt to free up possible stuck ring on piston #2. Will measure compression in a few months to learn if it's up.

 

 

 

 

Edited June 27, 2021 by keithb7

[harmony]

4 hours ago, keithb7 said:

Thanks @sidevalvepete.

 

Earlier in this thread I did mention the task of performing a valve set. I did complete that work last Saturday. There were no tight valves. Most all were 0.002 to 0.0035 wider than spec. Could be the previous owner set them wider for a long hi-way trip. I re-set them all cold, hot spec plus 0.002". The valve set seemed to offer a some torque improvement. Glad I did it. 

 

I also forgot to mention that I yanked out the earlier 35, 36 & early '38 style breaker plate and points. The points were hard to find. I have a pair now. But it took a month to get them. I went with the later '38 and up style of points and breaker plate. I have several spare sets of these later style points. This did indeed offer up improved engine performance too.  The old style points had been over tightened at some point. The lock down nut threads were stripped.I found the dwell would not hold where I set it at, 38 degrees. Digging in further I found the bad points.

 

I found quite a few things to get this car dialed in. I gained some great experience along the way.

In summary:

 

-Bad coil wire at internal rear of coil. Exposed wire strands possibly going to ground intermittently.

-A non-stock spring inserted above check ball, under set screw for accelerator pump circuit

-Bad points anchor bolt. Stripped threads. Would not lock down and hold the set gap. 

-Incorrect sized BB's in the carb valves for intake and outlet of accelerator pump. Found both BB's same size.

-Valve lash wider than spec

-Oil mist inside distributor cap

-Air leak at carb base adaptor place. Gasket shriveled up and shrunk. 

-Accelerator pump leather cup hard and stiff. Could not maintain steady flow of raw fuel stream

-Adjusted float level to spec

-Re-tensioned spark plug wire caps that anchor to spark plug.  Getting loose.

- Added carb base plate heat shield

-Added heat shield at front bottom of exh manifold to assist keeping fuel pump cool

-Removed incorrect fuel pump and pressure regulator

-Installed stock type mechanical fuel pump, without built-in air pump

 

Every step that was addressed seem to add some improvement. I will continue to add Marvel Mystery Oil to my fuel tank. In an attempt to free up possible stuck ring on piston #2. Will measure compression in a few months to learn if it's up.

 

 

 

 

Just to reiterate what you've said here and on your you tube channel.  The fun is discovering issues and solving them.  I've kept a pretty accurate log of my old girl "Harmony" since I got her.  The list of things I've done to her to either improve her, or to undo someone's blunder in years gone by is humongous.  It's so rewarding so solve even the smallest hiccup.

[Sam Buchanan]

21 hours ago, Plymouthy Adams said:

as for the non-ethanol...yeah I would prefer it but my cars are also built to run on ethanol..it is still a better blend that what was at the pump in 1952..the only time I spare the change for non-ethanol is my small engines, chainsaws, weedeater and blower etc.  My mower rarely will set as if I am not mowing grass, in winter I am mulching leaves....never has time to go stale.

 

Same here. My P15 is very happy with whatever that stuff is that comes out of the pump when you press the '87' button. I don't use any additives, either.

[dwest999]

Great stuff on this thread.  Like Keith, I am trying to get a P10 back up and on the road after sitting a long time.  I, like many others, have benefited from the forum and Keith's YouTube (which is a must watch for anyone who owns an old mopar).  I rebuilt my carb this past weekend and found both the accelerator pump and step up binding and not moving up and down as it should.  I'm hoping that helps.  I also have the distributor out getting rebuilt as there appears to be something going on in the internals (as I've changed the points and condenser and other parts) already.  Hoping to get the car running soon.

[desoto1939]

On the Autolite Dizzy cap I thought there should be a small rubber plug that comes with the cap and that this hole should closed with the plug.  I will have to find one of my Autolite caps for my 39 Desoto and see if they have the smallpiece of paper with the instructions regarding the plug.

 

SInce you brought up the fact regarding the two small ball bearings being in the wrong holes.  This is why I always suugest that you get a couple of cardboard egg cartoon and number is slot. So that when you dissasemble the carb you put each individual part into a numbered slot.  This way nothing gets out of order. And when you reassemble you just start with the last slot and go backwards.  This will eleminate the confusion and not put the wrong ball into the wrong location.  You can also use a daily pill container from your dollar store or Pharmacy.

 

Rich Hartung