Fluid Drive Stalling

[Fleetwood Meadow]

I have a 1951 Dodge Meadowbrook with the standard 3 speed transmission fluid drive. When it is idling in neutral it runs around 450-500rpm. When I put it in gear and take out the clutch the engine bogs down to around 200-250rpm. I have changed the fluid with the TDH ISO32 like many of the forums here have said to do and it still does it. When I try to take off with the clutch out it either stalls or stumbles for about a second then takes off. When I am rolling down the road it runs and shifts fine with no hesitation. When you have it in gear with the clutch out, lets say in second gear, and you release the brake without pushing the accelerator it pushes the car forward like it would in an automatic transmission. Is the engine supposed to lower rpms when in gear with no clutch and no acceleration? Is something getting hung up and causing it to act like a normal standard transmission?

[plymouthcranbrook]

Try posting to P15/D24 site.  Lots of knowledgeable folks there:

 

http://p15-d24.com/page/index.html

[Rusty_OToole]

Idle may be a little on the high side but not much, I believe it is supposed to be 400RPM. Yes the car is supposed to move forward when it is in gear and the clutch released. Like an auto trans. It should take off smoothly without stalling or stumbling. Maybe the choke is letting off early, maybe the engine is out of tune. Have you done a compression test and tuneup? It sounds like the transmission and Fluid Drive unit  are working correctly but the engine is a little off tune.

[JACK M]

13 hours ago, Rusty_OToole said:

Idle may be a little on the high side but not much, I believe it is supposed to be 400RPM. Yes the car is supposed to move forward when it is in gear and the clutch released. Like an auto trans. It should take off smoothly without stalling or stumbling. Maybe the choke is letting off early, maybe the engine is out of tune. Have you done a compression test and tuneup? It sounds like the transmission and Fluid Drive unit  are working correctly but the engine is a little off tune.

 

My thoughts as well, Maybe an accelerator pump.

[c49er]

The engine probably needs a good compression check and the tune up parts checked over and maybe replaced.

As mentioned it sounds like a accelerator pump leather is weak.Possibly plugged pump jet. Cause of hesitation when accelerating. Step up piston gasket could be missing or damaged too.

Basically some careful yearly maintenance might be in need.

[Rusty_OToole]

One often overlooked part is the automatic choke. The bimetallic spring loses its tension over the years. They do turn up on Ebay from time to time.

 

I would start by doing a compression test. Those engines are so well behaved they will continue to run smoothly with no bangs or knocks in an advanced state of wear. If the compression is above 90 in all cylinders and no more than 10 pounds difference between cylinders it should be possible to make it run like a top.

 

The tuneup is something of a lost art. It is no longer necessary on cars with electronic ignition, which is all cars since the mid seventies, and fuel injection, which is all cars since the mid eighties.

 

A carburetor clean and overhaul used to be part of a tuneup. If you decide to do this get a good name brand carb kit but don't go by the instruction sheet. They are incomplete and filled with errors. Get the original factory manual, either from the car maker or the carburetor maker and go by the specs for your car. Don't go getting ideas of your own. Cook book it together according to the directions.

 

Or, if the throttle shaft is worn and it hasn't been properly rebuilt in decades it might be better to send it away to be rebuilt by the Carb King.

 

Another thing, many times the ignition timing mark on the vibration damper slips and is not in the right place. Chrysler gets around this by putting a pipe plug in the head above #6 piston. You can take out the plug and drop a screwdriver in the hole and measure the piston's distance before TDC. Since #1 and #6 rise and fall together this makes double checking the timing a cinch.

Edited April 17, 2018 by Rusty_OToole (see edit history)

[Fleetwood Meadow]

19 hours ago, Rusty_OToole said:

Idle may be a little on the high side but not much, I believe it is supposed to be 400RPM. 

I posted this on the p15-d24 forum and everyone said that the car sounds like its running perfectly, which it obviously isn't or I wouldn't be complaining about it. They all told me to raise the rpm to 600rpm. The book says it should be 450-500rpm. 

[Fleetwood Meadow]

I rebuilt the carburetor two months ago, including the accelerator pump. I am not very knowledge on carburetors but the book says I should have a Stromberg BXVD-3 or a BXVES-3 on it but it came with a Stromberg BXV which does not have a dashpot to retard the rapid deceleration. But the car stumbles to rev in neutral as much. That is another topic I plan to tackle. If someone can tell me the difference between the carburetors I would love to know if it is worth replacing to the factory stock carburetor. 

 

As for the fluid drive, I was told that when it gear without the clutch the rpm will drop down when stopped but it drops down enough to start discharging the battery and then trying to take off it stumbles and either stalls or it catches enough of the rev to take off. I have watched a couple videos online and their cars don't drop down so much, maybe 100rpm. It is almost like something is grabbing, but I know that nothing touches in the converter, that the fluid creates the pressure to move the turbine. 

 

I did a compression test and it wasn't overly impressive. The shop manual says that with all the plugs out and the throttle wide open the compression should be 120-150. This is how mine read:

1: 85

2: 90

3: 92

4: 92

5: 100

6: 100

 

The compression test was completed twice with the same results.

[Fleetwood Meadow]

7 hours ago, c49er said:

Step up piston gasket could be missing or damaged too.

I'm not overly familiar with the inner workings of the carburetor. What is the step up piston and where would I find it?

[Fleetwood Meadow]

Could a leak in the intake manifold cause the hesitation at initial acceleration? Could it run itself too lean initially and then straighten out?

[Ben Bruce aka First Born]

 I am going to jump in with both feet.  For whatever reason, I think you are starving for gas. 

 

  Ben

[61polara]

I agree, this is a carb problem.   It sounds like a low speed idle circuit problem.  How did you clean the carb body and passageways?

[Fleetwood Meadow]

I cannot remember exactly what I used but it was a degreasing agent that I let the parts soak in then I scrubbed them with a rotating brush that looks like an electric toothbrush. 

[Fleetwood Meadow]

I have corrected the accelerator pump issue that I did not know I was having. The throttle shaft was wiggling where the linkage connects. I secured it. The accelerator pump was not going up enough for it to get a long stream, it stopped about halfway through the throttle opening. I added a couple washers that are the size of the linkage so it won’t bind. Now when idling and the pedal is pressed it revs beautifully. I increased the idle to 700rpm and when I put it in gear and released the clutch it dropped down to 350rpm. I  released the brake, pushed the accelerator, and.... it stalled. So I started it again, put it in gear, released the clutch (dropped to 350rpm again), I pushed the accelerator very very slowly so it started to raise the rpms, released the brake and it took off very slowly. So obviously the issue is that the engine drops too low in gear when stopped. How do I correct that? Even at 700rpm idle it dropped in half. So does that mean I need to put the idle at 800-900 to get 400-450 in gear at stop? I know that can’t make sense to do. 

[Rusty_OToole]

Hate to say it but your problem may be a worn out engine. Compression numbers like yours indicate it is time for an overhaul or rebuild. In the meantime don't set your idle too high. Hold the throttle open slightly with your foot if you have to or baby the throttle and clutch  taking off. The clutch is very small, I don't like to slip the clutch or use it any more than I have to on those models.

[Spinneyhill]

Did you do the compression test after a spoonful of oil in each cylinder (not on top of the valves, but into the cylinder)? This wet test will indicate if you have worn rings or not.

 

Other wise, get a vacuum gauge and look up on the www how to diagnose the engine from the readings.

 

The BXV-3 (?) is probably off an earlier model?

[JACK M]

On ‎4‎/‎17‎/‎2018 at 5:28 PM, 51Meadowbrook said:

Could a leak in the intake manifold cause the hesitation at initial acceleration? Could it run itself too lean initially and then straighten out?

 

I think yes.

[Fleetwood Meadow]

It turns out I did have an intake leak. I fixed that however it didn’t change things. Prior to that I ran my Meadowbrook around for about an hour and a half the other day and it stumbled and did everything I mentioned before. Then about an hour into the ride it stopped dragging at the stops and didn’t stumbled when I took off. I assumed that the fluid finally worked through and everything was great. The next day I took it for a short 15 minute ride and it acted up like before the whole time. Today I took it out for about an hour and it did the same as the longer drive I mentioned, for the first half of the ride it acted up then it started running beautifully. Is this just one of the finicky cars that is angry until the transmission heats up enough and then it runs great? Its such a pleasure to drive when it runs without problem. 

[Spinneyhill]

Automatic choke fitted? If so, is it working properly?

[Fleetwood Meadow]

Before I leave the driveway the car is already up to temp according to the gauge and the choke has been released. 

[tom_in_nh]

Has the Fluid Drive been apart?

After reading this post from start to finish, this would be the next area to focus on.

Good luck,

Tom

[61polara]

I still believe this is a carb issue.  It sounds like you did a great job cleaning the outside of the carb, but the internal passages are still blocked.  Did you blow out the internal passages with compressed air to clear them?  If not, you need to do another carb overhaul.  Contact CarbKing on here and buy a rebuilt carb from him.  I'll bet your problem will go away.  Don't get into the fluid drive until you know you have a good carb.

[c49er]

There's not much in a fluid drive coup[ling to cause your problem.Leave it alone...I've worked on many with seal leak issues.

Don't let anyone cut it open to rebuild it or you will be possibly in a world of hurt..the vanes don't bend and if the bearing was bad you would feel and hear it.

[Fleetwood Meadow]

I am starting to believe that it is not the fluid drive and more of a carburetor issue. That brings me back to the carburetor post I made earlier in this thread. Is the carburetor letting it get too low in the rpms because it doesn’t have the dashpot or is that just a gimmick? I have read many saying they don’t even use it. I had read that the area around the throttle shaft starts to create an air leak over time. Does that make sense? 

[Spinneyhill]

If you can wiggle the throttle butterfly shaft much, it needs to be bushed. It will be sucking air, giving a lean mixture.

[Fleetwood Meadow]

I tried to wiggle it around and it is tight. Does the TDH ISO 32 get thinner or thicker when it warms up? The issues I’ve talked about seem to happen when the car has been running for less than an hour. 

[61polara]

Let's go back to basics.  How did the car run before you overhauled the carb?  Before you get into more involved areas, have the carb professionally overhauled.

[Fleetwood Meadow]

The car ran the same as it does now except the stumble never went away. 

[carbking]

Just a suggestion: before doing anything else, get the identification number from the top of the carburetor (stamped into the metal, NOT a raised number) so we can determine how much of a mis-match the BXV is for the fluid drive.

 

I tend to believe the compression is significantly low, but the wrong carb might be contributing to the overall problem.

 

The BXV, BXVD, and BXVES are types or styles of carburetor. They come in all different sizes and calibrations. Simply stating you have a BXV is about as informative as me calling my doctor and telling him my feet hurt! More information can suggest if the carburetor is part of the problem, or not.

 

If the carb is an O.E. application, then looking straight down on a CLEAN top casting in the area approximately above where the fuel inlet enters the bowl should yield the identification number. If Dodge, it will be in the format 3-nn, or 3-nnl, or 3-nnn or 3-nnnl. The 3 represents Dodge. The small nn or nnn represent an unknown 2 or three digit number. The small l represents a letter (A,B,C, etc.) that states the engineering status of the carburetor. No major revisions, no letter. One major revision, letter A. Two major revisions, letter B, etc. Example 3-97 (3=Dodge, 97=identification number). Second example 3-95B (3=Dodge, 95=identification number, B means 2 major revisions).

 

Jon.

[Fleetwood Meadow]

[Fleetwood Meadow]

So i took the pictures and put them up for comments and nobody has said anything. The top of the carburetor where the dashpot would be if it was the right carburetor says 15-20A. The cast iron part says BXV-3. 

[Spinneyhill]

Patience sir. One must wait for the right person to come along.

[Fleetwood Meadow]

Doing my own research it seems the 15 stands for Plymouth and the 20 means it was the 20th carburetor the manufacturer made and the A was an engineering revision. Was this revision a rebuild by the engineers to fix this particular carburetor or what could the A be for?