Carb issues

[Kool48]

I've recently rebuilt my Carter bb carberurator on my 48 Plymouth.   It has to have a vacuume leak somewhere.   I've taken top off.  Double checked float setting 5/64 per instructions. Accelerator pump 3/8 travel.    All good.  Everything is cleaned blown out and free moving.      Car runs like crap.   Have to choke the heck out of it.      Well I was under car today and noticed this.    This is a pic of the bottom side of my intake.    Should there be a plate and gasket there? 

[DrDoctor]

   I believe the original exhaust manifold fits up against the intake manifold there. It appears that you have tube headers in lieu of the exhaust manifold, so in your case—yes, you need to block off that opening.

[55 Fargo]

Just make a metal plate and bolt it onto the bottom of the intake.

This used to be your "heatriser" chamber.

Even if you left it probably wouldn't do anything, but putting a cover may haelp deflect heat under hood in summer....

[55 Fargo]

I would pull the carb again and make 100%sure its clean in every passage, did you soak it and pull it completely apart?It sure sounds like the main jet, is obstructed, possibly.

Check the firing order, your plug wires too.

If you have to choke it to get it to run or smooth out, you are fuel starving....

[Don Coatney]

Being as your intake and exhaust manifold are no longer "married" leaving that cavity open should have no effect on how your engine  runs. Is your intake manifold gasket leaking? Have you taken a vacuum reading on your engine? Is your vacuum advance on the distributor working correctly? If the vacuum advance rubber is shot that may cause a lean mixture.

[Kool48]

12 hours ago, DrDoctor said:

   I believe the original exhaust manifold fits up against the intake manifold there. It appears that you have tube headers in lieu of the exhaust manifold, so in your case—yes, you need to block off that opening.

I'm going to make a cover plate , thanks.  

[Kool48]

11 hours ago, 55 Fargo Spitfire said:

I would pull the carb again and make 100%sure its clean in every passage, did you soak it and pull it completely apart?It sure sounds like the main jet, is obstructed, possibly.

Check the firing order, your plug wires too.

If you have to choke it to get it to run or smooth out, you are fuel starving....

I cleaned the carb very thoroughly,  using small wire to get it to the small areas.    The car ran fairly good before,  but had some hard starts and I just wanted a fresh carb.    Firing order is good , plugs are tan color around electrode.   If I run the idle mixture screw all the way in it does make the engine want to die.    I find it smooths out better about 1 1/4 turn out from seat position.    I did learn last night. Vacum advance dighram is shot.   I tried pulling a vacum on port and you hear the air seeping at he dighram end and the arm does not move in as should when vacuum is applie .   I've read to not worry about the vacum advance.  Just plug it off at carb ?    Not sure if that's correct or not.   Searched last night for new vacuum advance parts.  No luck.     So I'm going to try and find points and condenser today in town and get it fired up again.   Points and condenser were new.  But as I pulled the distributor last nite.  The wire coming out of distributor from points hit my positive post on battery and distributor was still contacting  ground.   So believe I Fried my condenser. And points.        Prior to all this.   Car started and ran descent.  Not great buy descent.  Carb work is where things went really south.       One other issue now is. The car was converted to 12 Volts before I got it.  It still has original 6 volt starter,  which is now making bad noises from being hit with 12 Volts over time.    Do they have a 12 volt starter that'll fit on this 48 ?      Thanks for everything.   Chris 

[Oberstar]

Chris, you have a lot of symptoms flying around in your head right now.  It's times like this where I step away from the vehicle for a handful of hours, think about the various issues, prioritize them, and then come up with a plan of action.  Start back with ignition- grounding, firing order, points- (I'll place a bet on your timing)

While in the military, we had a saying- "Plan your dive, dive your plan"  Don't jump from exhaust to manifold to condenser to points to vacuum advance, etc...

In my experience- If hooked up properly, 12v battery should not overtask a 6v starter, unless your hard starting issues cause you to lay down on the starter too long and causing it to overheat.

[busycoupe]

You said that the advance diaphragm is shot, but you did not say if you tested the manifold vacuum.  I would start with that, then try to plug the leaks until you get 16 to 21 inches of Hg at idle.  Does your car have vacuum wipers? The vacuum hose from the manifold to the wipers is another source of leakage.  

[Kool48]

Ok.  Just got home a bit ago.  Had to replace points and condenser do to my fault.  I shorted the condenser out removing distributor yesterday.  Anyways that's fixed.  Set point gap @ .020. It's all look good and are set @ .025.  I had to loan the bracket on bottom of distributor to be able to get the pointer and TDC Mark on balancer in line with one another.   So now my travel is approximately 6 degrees before or after TDC.  I'm @ TDC.    I also had my vacum guage on the vacum port of carb.    I can only get about 9"s of vacum at idle.   On my old meter. I'm running about 5600rpm and 31 degrees dwell.    Car starts right up fast. Not sure if it's advanced to much or because of 12 Volts hitting the 6 volt starte .  Which is starting to make noise.  I'm gonna have to replace it soon.   As far as vacum wipers. Yes I have them.  But there not hooked up.  I have a line fed out of the rear of intake manifold. But it's plugged off.     I noticed this fuel line someone ran before me.   I just noticed it now.   It's about pinched shut and running right on radiator hose and heater hose.   So I know that's not good.  Could be starving for gas and also vapor locking.  So I'm gonna get new line and reroute it asap.    I did drive the car.  Leaving in 1st pretty good hit 2nd goes very well.  Get up to 3rd gear around 40 MPH and engine starts surging until you get out of the accelerator.  That was all with choke opened all the way.  I never tried to choke it to correct it.   But there a certain area when accelerating you hear this sucking sound from carb.  It's in a range of its own.  I'm wondering if throttle Rod may be my problem with the leak ?   If so can it be repaired ? When listening to engine here in drive.  You don't hear any signs of leakage. Except that sound coming right outta the carb itself.  You can cup your hand over it and it helps a bit.   I've shot either around everything I can think of and no changes.     Here's a couple pics.    Ya I know the fitting in carb isn't correct.   But that's what they had in it.  I'll get the correct vacuum fitting first it.   But it doesn't leak right now I know for sure.    Oh and here's my coil.  It has resistor in it 

[Kool48]

Well it won't let me upload anymore pics right now.  Sorry 

[Don Coatney]

Do you have a service manual?

[Kool48]

45 minutes ago, Don Coatney said:

Do you have a service manual?

Yes I do 

[plymjim]

  You obviously have more than one issue with your car however here's one

thing that will help. Make or purchase (Langdon's Stovebolt) a plate to bolt to the

bottom of the intake manifold where the heat riser used to be. This plate is to be

equipped with fittings to intercept your heater hose. When running headers & no

heat riser your carb will sweat & even frost up without some sort of heat source.

I am running two flatheads with this setup & it does make a difference in the way

the cars run.

 

[55 Fargo]

Have you got your air cleaner on?

That sound is pretty normal, and a certain range, you hear that old B&B carb a drawing air and fuel

9 inches of mercury, at idle, you got a leak somewhere, carb base, intake manifold, or some vacuum line source.

You should be 17-20 inches range at idle.

As mentioned up above, block off that opening the old heat riser chamber, but that is not your issue right now..

 

Edited April 14, 2017 by 55 Fargo Spitfire

[Don Coatney]

Connecting the vacuum gauge to the vacuum advance port at the base of the carburetor will not show true manifold vacuum. Connect the gauge directly to the intake manifold using the port for the vacuum wipers.

On an industrial engine that is designed to run at a governed speed the vacuum advance is not required. However on an automobile engine that runs at different speeds the vacuum advance will make the engine run more efficiently and economically. A vacuum advance causes the timing to advance when there is a load on the engine. Mechanical advance distributors only sense engine RPM, Contact the folks at Terrill Machine as I believe they rebuild vacuum advance units.

Terrill Machine Company
1008 CR 454 phone (254) 893-6006
Deleon, TX 76444

[Kool48]

5 hours ago, Don Coatney said:

Connecting the vacuum gauge to the vacuum advance port at the base of the carburetor will not show true manifold vacuum. Connect the gauge directly to the intake manifold using the port for the vacuum wipers.

On an industrial engine that is designed to run at a governed speed the vacuum advance is not required. However on an automobile engine that runs at different speeds the vacuum advance will make the engine run more efficiently and economically. A vacuum advance causes the timing to advance when there is a load on the engine. Mechanical advance distributors only sense engine RPM, Contact the folks at Terrill Machine as I believe they rebuild vacuum advance units.

Terrill Machine Company
1008 CR 454 phone (254) 893-6006
Deleon, TX 76444

Thank you Don 

[Kool48]

9 hours ago, 55 Fargo Spitfire said:

Have you got your air cleaner on?

That sound is pretty normal, and a certain range, you hear that old B&B carb a drawing air and fuel

9 inches of mercury, at idle, you got a leak somewhere, carb base, intake manifold, or some vacuum line source.

You should be 17-20 inches range at idle.

As mentioned up above, block off that opening the old heat riser chamber, but that is not your issue right now..

 

Yes I have a air cleaner.  But wasn't on engine when I explained the situation 

[Oberstar]

Chris, what are your plans now?  Let us know vacuum numbers at the intake port when you get a chance.  The plate issue is one thing, but the dizzy advance keeps nagging me as the priority issue.  But I'm just thinking out loud, and have almost zero credibility in comparison to a lot of the guys on this board

[Kool48]

Ok here is latest.   I got the  Engine running very good in my opinion.    Let's back up,   I've owned the car since last fall. The car  actually ran good when I got it.   Never had an issue with it     Just before winter set in I noticed the frost plugs were rusting out and leaking.   So I had to pull the distributor to change the frost plugs out.   Every since that repair I had a feeling the distributor didn't get back in as it came out.   Although I never turned the engine over or moved the car in anyway for the engine to rotate.   The car started back up , but never ran the same.   So something had gotten moved.   This is my 1st mopar.  I had took pics before removing anything and were everything was positioned. Cap to rotor distributor relationship to block etc..    When I got it back together it was like it was a tooth off.    I thought I could take a screw driver and turn the  oil pump stem to get rotor were I wanted it.  Like you do on a Chevy  engine.   But I guess you can't.    I couldn't turn the  oil pump.   So I just assumed it couldn't have gotten off a tooth.  The car ran but I had all this issues as mentioned earlier.      So today I went out and set the timing with my vacuum guage.   Connected to vacuum port on rear of intake manifold .And set the idle mixture screw using vacuum guage.  So my end results are at about 550 RPMs at idle it pulls 16/17 inches of vacuum.    Needle only jumps between 16 &17 inches.  Not dead steady but not jumping all over the place either.  Car stays at 165 degrees,    oil pressure @ 40 lbs . Doesn't smell gassy (rich) doesn't smoke.   Starts right up and runs like a top now.  I still am looking to get a replacement vacuum advance canister .  The only thing that's still bugging me is that to get it to run like it is now.  I had to readjust the lock plate on bottom of distributor a lot and also had to readjust my  oil fill tube for clearence do to the vacuum advance canister hitting it not allowing me to get the timing set to max vacuum .    My #1 position on cap is at the 6 o'clock position which I've read it should be around the 7 o'clock position. Then i wouldn't have had clearence issues with vacuum advance canister hitting fill tube.    I even tried rotating the wires to get it positioned right. But then it was to much.    Anyways. It's running great I just I could figure out how to get distributor in the correct position.      Also not that it matters much now , but putting my timing light on it at idle just as it is. The timing mark on the balancer is between 11 and 12   o'clock position looking at it from front of engine.  I know that the outer ring can sometimes slip but I have doubts that this one has but I don't really know for sure.  

Edited April 15, 2017 by Kool48

[55 Fargo]

Fantastic news, very happy for you, and a beautiful car.

16 17 is not bad, don't worry about a slight vacillating needle, mine does that too, maybe valves leaking slightly.

Good luck happy motoring and Happy easter

[Kool48]

23 minutes ago, 55 Fargo Spitfire said:

Fantastic news, very happy for you, and a beautiful car.

16 17 is not bad, don't worry about a slight vacillating needle, mine does that too, maybe valves leaking slightly.

Good luck happy motoring and Happy easter

Thank you,.  Happy Easter to you as well

[Andydodge]

Kool, nice car..........I'd be chasing a vaccum diaphragm or canister.......here in Oz they used to be a standard part that auto electricians carried, dunno if the same applies to the US, maybe try tractor or similar supply places........again, nice car........regards from Oz, andyd  

[DrDoctor]

   It appears as tho’ your problem is resolved. I also agree with the others—very nice car. Happy motoring!

[greg g]

Drive and enjoy.