UPDATE Page 2 — Question About My ‘26 Dodge’s Carburetor

[DB26]

Hey everyone,

I removed my carburetor from the block today to gain access to my coolant drain for repair. 
 

I noticed there was quite a bit of fuel inside the intake flange where the carb bolts on. It literally spilled out. 
 

I closed the fuel petcock and ran my carb out of fuel just 2 days ago. Is there a reason why so much fuel is built up in this area? Should I be concerned? 
 

 

 

Edited April 18, 2020 by DB26 (see edit history)

[nearchoclatetown]

Are you POSITIVE it's gas? There is no way fuel can go uphill to get there from the carb without engine vacuum. This may be the source of the leak from the coolant drain? 

[DB26]

I touched it and it smelled like gas. I just cleaned the area, so I’ll go back later and check again. 

[TonyAus]

Looking back to a previous post which showed a pool of fuel next to the carburettor I think you may have a flooding problem.  In respect of the first poll, you'll notice a small vent (raised section) under the float chamber cover.  If the needle valve is leaking or the float has sunk the excess fuel will exit there.  Also, the engine will suck up more  fuel that the carburettor can properly  atomize it and condense in the inlet tract.  This can also result from an incorrect mixture adjustment.  Both will result in black smoke from the exhaust.

 

Let the float chamber fill from the vacuum tank then turn off the fuel cock.  Remove the float chamber cover and check the fuel level.  It should be no higher than about 3/8" below the top of the chamber.  If higher, shake the float to see if it has any fuel in it.  Check the condition of the needle and seat - it may be well worn.  

 

 

[DB26]

Thank you. I will do this! 

[stakeside]

I did not understand the starting sequence for my Stewart/Detroit updraft. I had mine rebuilt Meyers so figured all would ok when starting my truck. Well I found out the choke has a different function than I thought. Most importantly you seldom  need to use the choke and if you do on cold mornings you use it to get a first fire of engine. You than push in choke. If you leave it out you will flood the carb.

The truck now starts right up.

I guess I have been educated again,

[TonyAus]

The approach I use for a cold start is to pull the choke out no more than 1/2" and let the engine run for about one minute before pushing it back.  This works for starts down to 5 degrees C.  More might be required for temperatures under that but I don't use the car in those circumstances.

[DB26]

Okay. It’s obvious now I have a carb problem. I’ve been ignoring it for a while, but the signs are getting worse. 
 

A few weeks ago I noticed I was getting white smoke when I would rev the engine up. very painful to the eyes. At first I thought it was residual 3 in 1 oil in my vacuum line. But now I doubt it. I pulled the vacuum line to check this today, the engine revved up with the vacuum leak and my engine blew a ton of white painful smoke and then died. 
 

And then there’s the idle. Most of the time it sounds like this:

 

 

And occasionally will sound great (to me)

 

 

And you can hear it change back and fourth in the exhaust:

 

 

I rebuilt this carb about a year ago. I have a second carb if I need it. I just ordered a new needle seat from Myers, which I did not replace before. 
 

I think first I need to see if I fully understood and currently understand how to properly adjust this carb. I thought I did. But I will re-read. Also, I will do the test that TonyAus mentioned soon. Yes 

Edited April 10, 2020 by DB26 (see edit history)

[TonyAus]

The white smoke sounds strange.  A rich fuel mixture burns black. I noticed in a previous post that you seem to missing the plates that go around the carburettor  intake between the cylinders.  Do you also have the pipe which connects the intake to the exhaust manifold?  If either of these are missing you could be sucking oil out of the valve chest.  In this case, the liquid running out of the block could be oil highly diluted with fuel.  Oil could also upset the mixture at idle, resulting in the variation shown above.

[DB26]

5 hours ago, TonyAus said:

The white smoke sounds strange.  A rich fuel mixture burns black. I noticed in a previous post that you seem to missing the plates that go around the carburettor  intake between the cylinders.  Do you also have the pipe which connects the intake to the exhaust manifold?  If either of these are missing you could be sucking oil out of the valve chest.  In this case, the liquid running out of the block could be oil highly diluted with fuel.  Oil could also upset the mixture at idle, resulting in the variation shown above.

The carb does not have a pipe connecting it. This is what the exhaust manifold looks like

 

 

What should be attached here? I have the 1926 6 Volt 4 Cylinder. 

Edited April 11, 2020 by DB26 (see edit history)

[TonyAus]

Bingo!  There should be a banana-shaped pipe here and two flat plates between the cylinders held together with a long stove bolt.  The holes in the plates hold the end of the pipe and the carburettor intake respectively.  The idea of this pipe is to direct hot air to the carburettor in very cold weather.  Normally, the engine runs on cooler air from holes in the intake which are uncovered by rotating the sleeve thereon.  Again, you could be sucking oil from the valve chamber.

 

Start looking for the missing bits.

[DB26]

I think I know what you’re talking about. WheelMang and JayG here on the forum supplied these pictures in a thread I made a long time ago. 
 

 

 

I thought I could get away without running the pipe. 
 

Anyone have any leads? 

[MikeC5]

I don't know guys.....  I've been running my '25 without that crossover pipe and have never noticed white smoke or adverse effects on the eyes.  I would associate white smoke with a head gasket leak or a crack in head or block (coolant entering the combustion chamber).  That might also explain the liquid you found in the intake.  Have you ever compression tested or leak down tested the cylinders?

[DB26]

11 minutes ago, MikeC5 said:

I don't know guys.....  I've been running my '25 without that crossover pipe and have never noticed white smoke or adverse effects on the eyes.  I would associate white smoke with a head gasket leak or a crack in head or block (coolant entering the combustion chamber).  That might also explain the liquid you found in the intake.  Have you ever compression tested or leak down tested the cylinders?

No I haven’t done that. I can do a compression test, I have the gauge. But have never done a leak done test before. 
 

The white smoke does NOT smell sweet at all. 

Edited April 12, 2020 by DB26 (see edit history)

[DB26]

Also, could a rich fuel mixture or a misfire cause the burning exhaust? 
 

If you watch the rough idle video I posted. Does that sound like a misfire? 

Edited April 12, 2020 by DB26 (see edit history)

[MikeC5]

A compression test would at least tell you if one cylinder or two adjacent cylinders are low compared to the others which would suggest an HG problem.  Do you mix the anti-freeze 50/50 with water?  If less, the smell might not be that obvious.  Since your car was running without the white smoke in the not too distant past, I wouldn't expect it's excessive oil burning from piston ring wear (oil burning smoke usually has a blue tinge also).  If it were rich running, as Tony mentioned, you would expect black exhaust smoke.  

[MikeC5]

I did watch your videos and it does sound like the engine has a loping idle.  Your 'painful to the eyes' comment makes me think poor combustion.  

[DB26]

10 minutes ago, MikeC5 said:

I did watch your videos and it does sound like the engine has a loping idle.  Your 'painful to the eyes' comment makes me think poor combustion.  

It only really smokes when I rev it up.

 

And the funny thing was, it wasn’t acting up too bad that day until I pulled a vacuum line as it was running. It revved up as you would expect from the vacuum leak and when I replaced the vacuum line back on, the engine started to lose rpm, smoke, and then It died. I started it back up and it idled again. 
 

I did recently put some NOS Rentz spark plugs from the 20s. Possible issue? 

[DB26]

And yes, I do a 50/50 mix, more or less.

[MikeC5]

It's hard to imagine that spark plugs would have a 'use by' date.  Which vacuum line did you remove?  

[DB26]

10 minutes ago, MikeC5 said:

It's hard to imagine that spark plugs would have a 'use by' date.  Which vacuum line did you remove?  

The one connecting my wipers. 
 

Now, I have a vacuum turn signal accessory on the car right now, which Tees off the main wiper line. That is currently plugged, as I am relocating it. I don’t believe there are any leaks there.
 

But the reason I pulled the wiper line I mentioned before, is because I was checking to see if there was any residual 3 in 1 oil in the vacuum line. The turn signals I had have been heavily oiled with 3 in 1, which the vacuum draw was sucking up. 

Edited April 12, 2020 by DB26 (see edit history)

[MikeC5]

I really don't think pulling the wiper vacuum line would cause any permanent changes in the system.  And even if you did get a few ounces of 3 in 1 oil sucked into the vacuum tank, it would mix with the gasoline and perhaps cause some oil smoke for a short time.  

[DB26]

Yeah, I was thinking the same thing. Just one of the theories that popped in my head. 

 

 

I’ll do the tests suggested here and report findings.

[Ron Lawson]

Going by the sound of the engine in your video it sounds very retarded Do you advance the spark after starting ?

 

[DB26]

10 hours ago, Ron Lawson said:

Going by the sound of the engine in your video it sounds very retarded Do you advance the spark after starting ?

 

I do. I go by what the book of information says. Slide the spark adjust to the right when starting and to left when running.  

[DB26]

I have a few videos to show off today.
 

To answer the question on how I start and run the engine in regards to the advance and retard. 
 

Here is my advance and retard handle. The video starts at full right “starting” position. And then I move it into running position:

 

 

Here is what the distributor does in respect to the handle movements:

 

And lastly, I took a video of one of the tests recommended to me. I filled the float bowl on the carb and then removed the top. Seems like the needle is working and the float does NOT have any fuel in it:

 

 

I will do a compression test tomorrow. 

 

Edited April 12, 2020 by DB26 (see edit history)

[JFranklin]

The idle sounds ok to me you just have it set too slow. 

[MikeC5]

Perhaps it could be a vacuum tank problem where the vacuum is not shutting off when can is full.  There is a valve that should close when the vacuum tank is full; if it doesn't, the tank will flood and fuel can flow down the vacuum supply line into the intake manifold, flooding the engine.  This hasn't happened to me but it has been mentioned as a problem in several threads over the years.  Perhaps this is where the extra fuel was coming from in your initial picture in this thread.  A way to test if this is what's happening would be to disconnect the line from the vacuum tank and plug the end.  Then run the engine on the fuel left in carb float bowl (and fuel that was in vacuum tank) and test if eye watering smoke goes away.  This would at least rule out or point to a vacuum tank issue.

[nearchoclatetown]

Another way to test it is to feel the vacuum tube while it is running rough. If it is cold it is sucking gas. 

[DB26]

Well, I swapped carbs and almost have it dialed in, but my battery died. So more adjusting tomorrow (and a new battery soon)

 

BUT...

 

I took a video of the exhaust pipe as she was running and I was wrong. It IS indeed black smoke coming from the exhaust. So obviously I’m burning rich somehow. More tests this week to further diagnose the issue, including: further adjustment of carb, compression test, analysis of distributor weights and movement, vacuum tank operation. 
 

Here is a video of the exhaust smoke:

 

 

[JFranklin]

You have the idle set way too low and I didn't see any smoke.

[DB26]

6 minutes ago, JFranklin said:

You have the idle set way too low and I didn't see any smoke.

Thank you, I will bump up the idle. 

 

I couldn’t keep it running long enough to get a good video (engine died when I put the choke in, and the battery wouldn’t turn the engine over after that), but when I give it the throttle at about 5 seconds, a little puff of black smoke comes out. I will get a better one when I have the carb adjusted more. 

Edited April 18, 2020 by DB26 (see edit history)

[DB26]

Well I just couldn’t resist. I went out there to see if the battery charged, it did. 
 

I did bump up the idle. 

 

I didn’t film the exhaust This time, but did film my issues with adjusting the carb.  
 

I followed the procedures for setting a bench adjustment in the Stewart Carb, which includes:

 

Seating the metering valve, just lifting it off its seat, and then adjusting the metering pin 1/16 down toward the gear casing. 
 

I then got the engine hot and tried to put the dash control all the way in. This lowered rpms significantly and almost killed the engine. I tried to adjust the knurled screw but the dash / choke control was no where near being seated. 
 

Here I am trying to push the dash control down to normal position:

 

Am I missing something? 

Edited April 18, 2020 by DB26 (see edit history)

[cahartley]

Yes you are missing something.

The current setup you have is nowhere near correct and now I know why you are getting black smoke.

The thumb screw is not for adjusting the idle speed.

It is for adjusting the idle fuel mixture but not in the normal way because that is not a "normal" carburetor.

The metering pin and rack are not properly "timed".

Now that I SEE what's what take a look at this thread >>> https://forums.aaca.org/topic/319822-1924-dodge-choke-set-up/

When I got my '24 DB I had the same trouble but the smoke wasn't white.......it was running way rich.

 

 

 

 

[DB26]

23 minutes ago, cahartley said:

Yes you are missing something.

The current setup you have is no where near correct and now I know why you are getting black smoke.

The thumb screw is not for adjusting the idle speed.

It is for adjusting the idle fuel mixture but not in the normal way because that is not a "normal" carburetor.

The metering pin and rack are not properly "timed".

Now that I SEE what's what take a look at this thread >>> https://forums.aaca.org/topic/319822-1924-dodge-choke-set-up/

When I got my '24 DB I had the same trouble but the smoke wasn't white.......it was running way rich.

 

 

 

 

I will check out your link:

 

Maybe I chose my words poorly, but I am aware that the knurled screw is not the idle. I bumped up the idle at the butterfly.

 

I started the car after follow these instructions for carb adjustment:

 

 

I had the knurled screw at half travel, I seated the metering valve and lowered metering pin to the 1/16 designation. The video you see is me trying to put the carb choke control back to normal operating position after setting the carb to the printed specs. I was following the “on car (final)” adjustment. 

 

Now, I did find this here on the forums:

 

Where user Steamcar had similar problems. 
 

User TonyAus2 said:

On 6/14/2010 at 9:05 PM, TonyAus2 said:

The 'official' method is described in Dyke's Carburettor Supplement. It prescribes. from memory, a metering pin protrusion of 1/8" into the bottom chamber. Following this instruction to the letter I found the mixture far too lean - the choke had to pulled at least half way out for the motor to run.

Find the choke point where the motor will run fairly well. Next step is to take the mixture lever off the splined shaft and replace it so it abuts the adjusting screw (which should be set halfway down its travel) - making sure that the splined shaft does not move in the process.

From here you should be able to adjust the mixture by ear - lean off until the motor pops and bangs on overrun - then enrichen until a smooth idle is obtained (warm motor of course).

My theory about failure of the 'official' method is that the different volatility of modern fuel requires a richer mixture than prescribed in the past. Does anyone have any other ideas?

Edited April 18, 2020 by DB26 (see edit history)

[DB26]

Bob Scafini also added this in the same thread:

 

with the carb off of the engine, and the upper part of the carb removed, take a hack saw blade and carve a slot in the bell crank shaft so that a screw driver will fit in the slot. slide the needle assembly into its opening, replace the spring and cap, slide the bell crank shaft into it's opening, slide the bell crank over a screwdriver, engage the slot in the shaft with the screw driver, turn the shaft raising the needle until it just lifts the dashpot, slide the bell crank onto the splines of the bell crank shaft using the screwdriver to maintain the location of the shaft such that the adjusting screw makes contact with the surface of the bell crank, tighten the screw securing the bell crank. turn the adjusting screw until the crank no longer lifts the dash pot. the key here is to keep the needle from sticking in the orifice of the dashpot. no further adjustment of the mixture is necessary.

 

[cahartley]

Are you CERTAIN the return spring IS, in fact, pulling the lever back all the way every time?

Something looks fishy.

 

[DB26]

3 minutes ago, cahartley said:

Are you CERTAIN the return spring IS, in fact, pulling the lever back all the way every time?

Something looks fishy.

 

I’m pretty certain it is. All the springs I witnessed seemed strong. 

[cahartley]

The reason I asked is because, at no time, should there be any space between the lever and the adjusting screw at idle.

Also bear in mind the setting is opposite what you likely think it is.

When you turn screw down you are enriching the mixture.

You have to think backward which isn't easy.

Many old Farmall tractor carbs have the same eccentricity as do many old Ensign carbs.......it can drive you nuts....... 

[DB26]

15 minutes ago, cahartley said:

The reason I asked is because, at no time, should there be any space between the lever and the adjusting screw at idle.

Also bear in mind the setting is opposite what you likely think it is.

When you turn screw down you are enriching the mixture.

You have to think backward which isn't easy.

Many old Farmall tractor carbs have the same eccentricity as do many old Ensign carbs.......it can drive you nuts....... 

yes it is certainly driving me nuts. And I know switching carbs was probably not the best thing to do when trying to troubleshoot a smoking exhaust / idle issue. But I wanted to give it a shot. I know these Stewart carbs are supposed to be pretty basic.

 

The only way it would run for me was when the bell crank lever was no where near the knurled adjusting screw. So it seems like car only likes to run on a richer mixture, which is in line with what TonyAus2 said. 
 

Would you advise against turning the adjustment richer like Tony suggests? Should I take the carb apart and reassemble to ensure accuracy? 
 

I will note that I believe the old carb was set according to Tonys procedure. I just remembered, I did this about 1.5 - 2 years ago.

 

Could that have been my original reason for raw fuel in my intake? If so, why would it take me so long to notice? The smoke wasn’t always there. Just recently it showed it. 
 

Could it be something else? Distributor / timing issue like what was previously mentioned? I still need to make an adapter to do a compression test. 

Edited April 18, 2020 by DB26 (see edit history)