Jump to content

Gas leaking from carburetor intake tube


GaryP65

Recommended Posts

Still having trouble getting it to start but noticed that after cranking (I confess, sometimes too much cranking), gas is pouring from the tube that leads to the block.

Is this just from too much cranking or is there another cause?

Patient is a 1925 12v positive ground Sedan.

Link to comment
Share on other sites

Sorry to hear the patient is still not responding :blink:.  At least you have a working starter now.  The tube through the block is your air intake and yes, you have been cranking too much and flooded the carb.  I suggest you leave it to evaporate but check out the ignition system and timing before trying again.

 

Ray. 

Link to comment
Share on other sites

Yeah. Nice to have a working starter. I think my switch is going thou. I adjusted the timing and it started last week for a couple of seconds. I get good spark too. What I don't get is... I get good spark, I'm getting fuel (aforementioned flooding) and it cranks. So why won't it start?

Edited by GaryP65 (see edit history)
Link to comment
Share on other sites

You say the switch is faulty.  Are you referring to the ignition switch?  They are often a cause of trouble or the starter/generator switch which you mentioned before?

 

The firing order is 1342. With a magneto you should have 0.012" or with distributor 0.20".  Plug gap 0.20" magneto or 0.30" distributor.  Plugs may be oiled up. Do they smell of petrol?  If they are wet it could be oil or (hopefully not) - water.

 

You might want to change the condenser and coil for good measure.  How old is the fuel? Stale fuel is no good.  Ethanol in fuel produces a lot of water.

 

Check compressions - they should all be around 50psi.  Check your carb float is not punctured.  Make sure the metering valve in the carb is not sticking and that the rack and pinion mechanism is working as it should.  Check that you don't have a gasket leak between the manifold and the block.  With the choke closed (be sure the cable is pulling efficiently) and the ignition fully retarded if there is a good spark the engine should fire.  

 

Best of luck 

 

Ray.

Link to comment
Share on other sites

My guess would be timing. Once you get it running, you can tell by manipulating the advance lever if the timing is advanced or retarded, but getting it close enough to start in the first place can be challenging. 

 

You may well be right but Gary has said that he has "adjusted the timing".  I assume the static timing has been set correctly in accordance with the manual.

 

Ray. 

Link to comment
Share on other sites

The Stewart Warner carb is a remarkably simple but effective device which seldom gives trouble.  Sometimes, however, a tooth can break off the pinion making a rich (cold start)  mixture unobtainable.  It is sometimes possible to effect a repair which restores enough of the rack and pinion action to lift the metering valve.  Under normal working the metering valve is lifted off it's seat by the suction action of the engine and therefore needs to move freely.

 

If you have not already done so, I would recommend getting hold of a Mechanics Instruction manual and/or a Dodge Brothers "book of information" for your year model.

 

Ray.            

Edited by R.White (see edit history)
Link to comment
Share on other sites

Still having trouble getting it to start but noticed that after cranking (I confess, sometimes too much cranking), gas is pouring from the tube that leads to the block.

Is this just from too much cranking or is there another cause?

Patient is a 1925 12v positive ground Sedan.

Gary, The fuel leaking from the tube going through the cylinders is likely NOT a carb. problem but rather a vacuum tank problem in the vacc port not completely shutting off so it fills not only the inner tank but both tanks  and eventually drawing raw fuel down the vacc line past the carb thus flooding the engine. Good Luck.

  • Like 1
Link to comment
Share on other sites

Gary, The fuel leaking from the tube going through the cylinders is likely NOT a carb. problem but rather a vacuum tank problem in the vacc port not completely shutting off so it fills not only the inner tank but both tanks  and eventually drawing raw fuel down the vacc line past the carb thus flooding the engine. Good Luck.

 

I had this problem but it didn't prevent the engine.from firing.  Just made it run too rich with explosions in the tail pipe.  

 

Maybe Gary's patient is more sick than we realise! :o

Link to comment
Share on other sites

Here's the run down...

Fixed the 3rd brush spring, changed the cable to foot switch, engine cranks fast, vacuum tank is in great shape (float works, new gaskets, interior guts are good and working, new carb gasket, new oil pan gaskets, new oil pump gaskets, used clear fuel tubes from gas can (won't use fuel tank until it starts - THEN will clean tank), clear lines go to vacuum to carb. No gas is getting to carb from intake tube! I see gas get sucked up from can to vacuum tank (I prime first). I see gas from vacuum to carb. I have a mechanics manual, book of information and any other literature available for this car. I've 'adjusted' the timing as the book describes and confident it is good. I have alway suspected it was electrical so I checked for spark (was never confident my coil was good). In the beginning I was not getting spark then one day I did, don't know why but one time IT STARTED. After that nothing. Checked for spark again and NOTHING. don't know why!. I'm thinking it's of getting ANY coil to hook up to test it put. I have new plugs in. New wires but never attached them but did check the old ones for continuity.

It's not the patient, it's the doctor!

Thoughts?

Edited by GaryP65 (see edit history)
Link to comment
Share on other sites

Have you tried bypassing the ignition switch by running a hot wire from the battery to the coil and THEN check for spark?

What you explained above could be as simple as a poorly grounded condenser but until you get consistent spark........well........you know.......  ;)

  • Like 1
Link to comment
Share on other sites

Have you tried bypassing the ignition switch by running a hot wire from the battery to the coil and THEN check for spark?

What you explained above could be as simple as a poorly grounded condenser but until you get consistent spark........well........you know.......  ;)

I have tried to by pass the foot switch when I thought it was shot (its not, because it works when I step on it). Just not sure how strong it is.

I hooked up jumper cables straight from the battery and it cranked but I did not check the spark. I think I'll check that one out.

 

How did this thread go from Carbs to Electric? Please, no comment from you Ray!

Edited by GaryP65 (see edit history)
  • Like 1
Link to comment
Share on other sites

  • 2 weeks later...

GaryP65, did you ever get it to start?

 

Just to double-check the timing, you could try setting the distributor so that, when cranking it by hand, it is firing no. 1 (i.e., rotor button pointing at no. 1 and points just opening with the spark lever fully retarded) just after the no. 4 exhaust valve closes. I got this from the instruction manual for my late '22, and I think it would apply to your '25.

Link to comment
Share on other sites

Like in the other post, if no compression on a cylinder , it may be a stuck open intake valve, no compression means no vacum to pull gas in cylinder , when piston comes back up it push fuel back to the Carburator.

If you have - at least 50 psi on all cylinders, correct timing , and fuel , it will run,

Jesse

Link to comment
Share on other sites

You could try doing a crude compression test where you get a tapered rubber stopper to plug up the spark plug hole (with all other plugs removed) and hand crank.  I would think any gross differences would be apparent in the relative force the cork gets popped out.   

Edited by MikeC5 (see edit history)
Link to comment
Share on other sites

For a quick check that you have enough compression to start, just place your thumb over the plug hole while the engine is cranked.  Personally, I doubt that's your patient's complaint.  You haven't said if the cold start manual mixture control mechanism inside the carb is working o.k.   If the rack or pinion is damaged, which is quite common, you won't be able to get a cold engine to start no matter what the compressions are.

 

Ray.

Link to comment
Share on other sites

I use starting fluid with no adverse effects, it is great on cars that vapor lock, I used it on 3 different cars a few weeks back during cousin the coast, Especially on cars that turn slowly when they or hot, , if you consider cars that run on propane , it no dryer then propane.

Link to comment
Share on other sites

  • 2 weeks later...

Let's get this on back on track....

It is only about carbs!

Maybe it's me but I can seem to understand the info in the book of info regarding the carb adjustment. I hear that the DB store has a book that would help but is there someplace online (or anyone here that can help)?

I think the store is upstate NY correct? If so, maybe I'll take a ride there.

Edited by GaryP65 (see edit history)
Link to comment
Share on other sites

  • 2 weeks later...

EUREKA!! Finally got the old girl started! Apparently I had the timing WAY off.

I will admit I had to use starting fluid but she fire up once the gas got drawn up the tube from the gas can even with priming the vacuum tank. Unfortunately, it will not stay started for to long. A few times once it shut off, gas was pouring out of the intake tube.

Link to comment
Share on other sites

So I decided to give the float a second look. Apparently there is a leak and it has some gas in it. This I don't understand since some time ago, I checked this out by submerging it on a bowl of water and it didn't bubble so I assumed it was OK

For some reason that is not the case anymore. Not being that familiar with this unit, is is safe to say that if it's full of gas, it will think the chamber is empty and will keep gas flowing into it?

Since a repair is necessary, how do you suggest repair? Do I braze it? Would that add too much weight? Is there another acceptable method? Maybe silicone or the like?

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...