GaryP65

Too much gas!

Recommended Posts

GaryP65    55

So I don't know what happened but here's the scenario:

 

car ran fine, started up with no problems albeit slow turn over.

car died while test driving it, turns out the SG needed help.

sent SG to Meyers, came back, installed, turns the motor over real fast (faster than before)!

now I have gas pouring out of the exhaust pipe at the carb and float bowl.

 

Share this post


Link to post
Share on other sites
Spinneyhill    250

Speck of dirt stuck under the needle in the seat at the carb, thus fuel flow continuous and the engine drowns?

 

Remove needle and seat, blow out, ensure clean, re-install. Check the float is still floating while in there.

Share this post


Link to post
Share on other sites
cahartley    223

If it floods only while the engine is running it's the vacuum tank.

If it floods until the vacuum tank has run dry it's the float needle in the carburetor.

  • Like 1

Share this post


Link to post
Share on other sites
GaryP65    55

So now that the holidays are over. I headed out the the garage and took the carb apart and cleaned it completely. Unfortunately i am still having the same issue. Car runs fine but when its off and I return after a few hours, there is gas leaking from the float bowl and possibly the bottom gasket (I say possibly because it may be trickling down from the float). The float is good. No leaks. Needle was removed from the rack and cleaned

 

Also, anyone have an idea on how to set the needle in the rack prior to assembly? is there a height or is it just suppose to barely open the valve? I feel I asked this before....

Share this post


Link to post
Share on other sites
cahartley    223

I think there's a photo of the tooth engagement in the Dodge Brothers Bible.

If you need it I'll scan it for you.

Share this post


Link to post
Share on other sites
GaryP65    55

Thank you but I thought you were referring to something more specific. I have the mechanics manual that has this but it doesn't show how high it should be set at.

 

 

Share this post


Link to post
Share on other sites
cahartley    223

If the rack and needle are properly engaged you make the additional setting using the thumbscrew.

The thumbscrew setting is opposite that of most conventional carburetors.

Turning it IN, clockwise, makes it richer so try turning it out a few turns and see if things improve.

Share this post


Link to post
Share on other sites
hchris    17

If I`m not mistaken, we are confusing one adjustment with another, the needle and rack adjustment is all about setting correct mixture whilst running.

 

My take on the problem presented, is that fuel is running out of the carb bowl whilst the engine is stationary,  if this is the case then the fault lies within the needle and seat in the float bowl, either the needle and seat are worn or the float setting is too high, causing the fuel to continue siphoning from the vac tank with the engine stopped.

 

As I recall, the fix for this is to adjust the float arms in the carb bowl.

 

ps: it could also be a sinking float, if the float has a hole in it, fuel will fill the float and sink to the bottom of the bowl, and then there is no way that the needle can be held closed to stop fuel running into the bowl. To test the float, remove from the carb and drop it into a container of hot water, if there is a hole, the heat will open it up and the float will fill and sink.

Share this post


Link to post
Share on other sites
GaryP65    55

I thought it was the float as well but I put in a new one last year but did not submerge it, only shook it to hear for gas. I do not think it's the float.

How do you adjust the arms?

 

FYI. Just to give you an idea of how I set the metering pin.

I set the adjustment screw in the middle of its travel and installed the bell crank arm to the point where I noticed the metering valve just start to open.

With the adjustment screw in the middle, I thought I would have enough adjustability. 

 

Before all this, I have good range on my choke adjustment. It was able to start well with it pulled out and all the way in once warmed up. Now it starts half way in and doesn't allow for any movement otherwise it won't run well if I move it.

 

 

 

Share this post


Link to post
Share on other sites
hchris    17

First of all you need to get the float setting right as its position obviously affects mixture. Not sure on the "how to" adjust the arms, looking at the schematic I imagine there is a way to adjust the levers at the top of the bowl cover, shouldn't be too hard to find the details with a search on the net. 

Share this post


Link to post
Share on other sites
JFranklin    71

That float needle valve set up is sure different to what I have ever played with. The image almost looked to be upside down.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

it

Share this post


Link to post
Share on other sites
hchris    17

First of all you need to get the float setting right as its position obviously affects mixture. Not sure on the "how to" adjust the arms, looking at the schematic I imagine there is a way to adjust the levers at the top of the bowl cover, shouldn't be too hard to find the details with a search on the net. 

 

 

Have a look at this, it might help you along.

 

http://old-carburetors.com/1927-Dykes/1927-Dykes-030.htm

Share this post


Link to post
Share on other sites
GaryP65    55

I have this article as well.

I do now agree that it seems to be a float height issue. Unsure on why as there is nothing wrong with the float itself (took it out and submerged it, all good).

I think I need to look at how the float needle sits in the chamber to shut off the supply. 

Share this post


Link to post
Share on other sites
Spinneyhill    250

It looks to me like the balance levers rise and push the needle down into the seat. So how do the balance levers "grasp" the needle? Is it just friction? If there were wear on the lever system they may not make strong enough contact to push the needle down into the seat?

 

Also, are the right balance levers in place for the float? if they are too heavy or too short, the float might not be buoyant enough to push the needle down?

 

So it seems to me the job is to carefully examine the float+balance lever+needle+seat system to understand how it works to figure out what is wrong with it and what adjustments are available to, hopefully, rectify the problem(s).

Share this post


Link to post
Share on other sites
JayG    32

Check the cylindrical part of the balance levers.  If they are flat on the top then they are worn and allowing the float to rise a little.  I believe that you can flip them if the bottom of the cylinder is still rounded.  

Share this post


Link to post
Share on other sites
carbking    280

Jay is correct about the fulcrum levers.

 

The original method of adjusting the float was:

 

(1) use a burette gauge to determine the fuel level in the bowl

(2) compare the fuel level in the bowl to the main discharge jet

(3) remove the bowl cover

(4) remove the fuel valve

(5) measure the distance from the collar to the top of the valve

(6) remove the solder on the collar

(7) reposition the collar

(8) resolder the collar

(9) repeat 1 through 9 as necessary

 

Being the lazy individual that I am, I came up with an alternate method of simply changing the thickness of the gasket under the fuel valve seat as necessary.

 

I also produced a few fuel valve/collar arrangements with a threaded collar that could be adjusted, and then set in place by a drop of blue loctite.

 

The gasket thickness trick will work. Just make certain there is no groove in the valve and/or no foreign material on the tip of the valve.

 

Jon.

Edited by carbking (see edit history)

Share this post


Link to post
Share on other sites
hchris    17
4 hours ago, carbking said:

Jay is correct about the fulcrum levers.

 

The original method of adjusting the float was:

 

(1) use a burette gauge to determine the fuel level in the bowl

(2) compare the fuel level in the bowl to the main discharge jet

(3) remove the bowl cover

(4) remove the fuel valve

(5) measure the distance from the collar to the top of the valve

(6) remove the solder on the collar

(7) reposition the collar

(8) resolder the collar

(9) repeat 1 through 9 as necessary

 

Being the lazy individual that I am, I came up with an alternate method of simply changing the thickness of the gasket under the fuel valve seat as necessary.

 

I also produced a few fuel valve/collar arrangements with a threaded collar that could be adjusted, and then set in place by a drop of blue loctite.

 

The gasket thickness trick will work. Just make certain there is no groove in the valve and/or no foreign material on the tip of the valve.

 

Jon.

 

So glad you chimed in Jon, I now remember doing the solder thing many moons ago on my Maxwell; washers under the seat would be the way to go. ;)

Share this post


Link to post
Share on other sites
GaryP65    55

One thing that gets me is that I removed the needle valve cap and if i push on the needle, it doesn't move. it seems seated in the valve!

If the levers were worn (and they are a little - who's isn't?), the needle would move a little and I would be able to shut the valve - correct?

Share this post


Link to post
Share on other sites
Spinneyhill    250

Does the needle have a smooth taper on the tip or does it have a groove in it? If there is a groove, it might allow a trickle of fuel past it, hence leakage will be noticed when engine is off, even though the needle is apparently seated as you describe above. Check that the needle has a smooth taper and the seat has a fairly sharp edge for it to seat against. Of course they should both be circular in the contact area and the circles should be perpendicular to the shaft of the needle.

Share this post


Link to post
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