Carburetor issue

[jdavidsmi]

I have a new to me issue with the carburetor on my 84 f150 with the 5.0 and a 2150 carburetor. On my way home last week I noticed a miss in the engine, and at a stop light the engine would slowly slow down and die like it had ran out of fuel. I thought the fuel filter may be getting clogged. It has a clear one that’s cleanable. This morning I checked it out and the filter is clear. I pulled the air cleaner off and started it up, it was very hard to start and would not idle.

The real strange thing was I had fuel bubbling up out of the two horns on the top of the carburetor. I don’t know the name of the horns. If I plugged them up the engine would die , it would run with one plugged but gas would shoot up out of the open one. Like there was a lot of back pressure.

Something going on, I have read a lot but did not find this discussed. Anyone have an idea?

Thanks

[Gary Lewis]

Your fuel level in the carb is too high.  But since you didn't do anything to make it higher I'm guessing that you got some bad fuel.  I had that once and it caused a similar problem.

I'd dump a can or two of cleaner in the gas tank and, if you are handy with the carb, pull it apart and clean the needle and seat.  I'd use isopropyl alcohol to do that and a Q-Tip.

[jdavidsmi]

Thanks Gary, Got to admit I’m not very good with carburetors. That’s why I just got a new one a couple of years ago. I will get the cleaner today and give it a shot.

[myrl883]

Float level is too high, sunk float, faulty needle and seat, or excessive fuel pressure. You aren't running an electric fuel pump are you??

[86 1/2 Brutus]

your float is set to high and the needle valve is sticking.   I'd be happy to rebuild the 2150 for you if you need.  Do you know how to check the float level and adjust it as need be?

[jdavidsmi]

Thanks to all for the information, when I picked up the cleaner I broke down and got a full rebuild kit. I have just parked it until we finish the harvest. Looks like about a week left.

This will be my first rebuild of a 2150, so I will take it slow.

On a side note, with the low oil pressure issue, just going to drive it for a while. I did not know that the pressure was low before I put in the new gauge, may have been this way for quite a while.

Still planning on pulling the motor out this winter, when it’s quiet. And see!!

[Gary Lewis]

I think a rebuild is a good idea.  However, if it is gum in the fuel you are likely to have the problem all over again until you get a good slug of carb cleaner mixed with that fuel.  Or, better yet, replace the fuel.

I was reminded yesterday of my experience with bad fuel - back in 1970.  We lived in Wichita and after filling up the Holly on the '69 Bee started flooding, badly.  It wouldn't idle and the fumes from the exhaust would make your eyes water.

I put two cans of carb cleaner in the tank and we took off for Salina, which is 90 miles away.  You could see the gas gauge going down, and we just made it to Salina when the gauge hit empty.  I dumped two more cans of cleaner in and filled it up again, and we started back for Wichita.  But it was still running horribly.

Jump forward to yesterday and as we passed the rest stop on I-35 just south of Salina I asked Janey if she remembered it.  She said "That's where you took the carb apart and cleaned the gum out of it."  And that's exactly what I did, finding a film of gum on the needles and seats that wouldn't let them seal.

So, if you had just filled up before the problem started I think you may have the same problem.  And if that tank is still full of that fuel you'll probably have the same problem as soon as you put that carb back on.

On the other hand, that may not be the problem.  So tell us more about what happened just prior to the first incident.

[jdavidsmi]

We finish up with the harvest Friday evening very late. Took Saturday off, until late in the day, when I remove the carburetor. Open it up this morning expecting to see a glaze over the inside, what I found was dirt and lots of it.

So I have sprayed it down with carburetor cleaner and letting it set for a while.

We have been using the truck in the fields and at what I guess was about a half a tank, I filled up from the farm tank. We used it for about 5 days before it started giving problems. Started off hard to start and keep running. Then it started what I thought was miss like it was running on 4 cylinders. Then it would not start at all. That’s when I found the issue with gas bubbling up from the horns, and I just parked it.

On a side note both pickups we use are gas and have been using the same fuel. Only this one has a problem. The Dodge is a 95 fuel injected.

It has a see through cleanable fuel filter between the pump and the carburetor and it never looked dirty.
So my guess is I had dirt in the bottom of the tank and bouncing around the fields was enough to stir it up.

I’m going to get the gas out of the tank and flush it out, maybe I should just replace the tank it is 36 years old.

[jdavidsmi]

Gary, my wife and I were stationed in Wichita from 79 to 84. We lived in Haysville, and worked on McConnell AFB. Moved from Fairbanks, Alaska, boy what a shock. wondering if we overlapped?

That’s when we had the 76 F250 highboy. It did not have AC, I sold it in 84 when I was sent to Shemya Island, that’s a small island at the end of the Aleutian chain, Bering Sea on the north and the North Pacific on the south.

The 76 was a beast of a truck, it would go anywhere, and if you could get it on the bed, it would haul it. 300 six with 4 speed. But it love the gas.

[old55pete]

I dont know about the rest of it, but from the looks of it, you need to find a better fuel filter. There may be dirt in the tank, granted. Still, at the end of the day. The fuel filter is supposed to stop that from happening.
Just as a common frame of referance, I understand preventive maintence on things like swathers, bailers, plow Cats and seed trucks and the like.

[Gary Lewis]

David - We didn't quite overlap.  Janey and I lived in Wichita from '69 when we were married to '75 when we moved to Ponca City, OK.  But during the summer of '69 I worked literally across the street from McConnell in the Boeing facility.

[jdavidsmi]

I have the carburetor cleaned and put back together, I have a couple of questions about vacuum ports and lines.

1st is the bowl vent left open, there is no hoses from the old canister.

2nd since this carburetor has an electric choke, shouldn’t the port on the bottom of the choke housing be plugged. It was not.

3rd. What should plug into this port? It comes out of the base of the carburetor, front of the choke.

[FuzzFace2]

old55pete wrote

I dont know about the rest of it, but from the looks of it, you need to find a better fuel filter. There may be dirt in the tank, granted. Still, at the end of the day. The fuel filter is supposed to stop that from happening.
Just as a common frame of referance, I understand preventive maintence on things like swathers, bailers, plow Cats and seed trucks and the like.

Yes a better filter is needed.
Them pull-a-part to clean are only good to stop small birds and that's it.
Also the glass part likes to break and you then have gas all over and maybe a fire!

jdavidsmi wrote

I have the carburetor cleaned and put back together, I have a couple of questions about vacuum ports and lines.

1st is the bowl vent left open, there is no hoses from the old canister.

2nd since this carburetor has an electric choke, shouldn’t the port on the bottom of the choke housing be plugged. It was not.

3rd. What should plug into this port? It comes out of the base of the carburetor, front of the choke.

1 Can you take a picture of the bowl vent but if you can put a cap on it you should be ok asthe bowl is vented to the air intake of the carb.

2 Picture of this choke also if you can.
It sounds like the choke uses both electric and heat to work.
My 300 six uses both to open the choke. The wire is not 12 volts but like 6 volts from the ALT "S" lug.

3 WAG that port is for the vacuum advance on the dist. at idle does it have vacuum or only when you give it a little throttle?
Dave ----

[Gary Lewis]

jdavidsmi wrote

I have the carburetor cleaned and put back together, I have a couple of questions about vacuum ports and lines.

1st is the bowl vent left open, there is no hoses from the old canister.

2nd since this carburetor has an electric choke, shouldn’t the port on the bottom of the choke housing be plugged. It was not.

3rd. What should plug into this port? It comes out of the base of the carburetor, front of the choke.

If you aren't running the charcoal canisters then leave the bowl vent open.

And the port on the bottom of the choke should certainly be plugged.  Otherwise you are pulling unfiltered air into the carb and then into the engine.

As for that port, I don't remember which port is which on those carbs.  But you want a "ported" connection, which means on that doesn't have vacuum when the engine is at idle but has full vacuum from just above idle all the way up.  And that fitting should be connected to the vacuum advance on the distributor.

[jdavidsmi]

I have an update and a new problem. I completed the overhaul of the carburetor, replace the fuel pump, replace all the flexible fuel lines, replace the gas tank, and pickup fuel level sender. And installed a better filter. I also put 5 gallons of gas in right from the station pump.
 
With the exception of the hard lines all the fuel components are new or rebuilt.

The new issue is I’m not getting any fuel to the carburetor.

As I thought about it this afternoon, I came up with 3 different possibilities.  Not enough fuel in tank, maybe I need to put in a second 5 gallons. New fuel pump no good, and 3rd is the cam is so warn and not operating the pump.

So tomorrow I will get a second can of gas and see if that does it. If not take the pump back for a replacement. I don’t want to address the cam yet.

Or I could just get an electric pump.

Any other things I should look at?  

[old55pete]

I know it is a PITA, before you start throwing more parts at it, put the old fuel pump back on as it was working when you took it off.

Putting another 5 gallions of fuel in the tank is a good idea. Then use air pressure and some rags to kinda seal the gas filler neck. Remove the fuel line at the fuel pump and lightly presurise the tank untill gas comes out of the line at the pump. if the pump is good it should pick it up and fill the carb in no time.

[86 1/2 Brutus]

Did you try to crank it with the carb empty, or did you put a little gas in the carb?  It takes a bit to get the system primed.  pur a few drops of gas in the venturi of the carb, crank the engine, it should start and stumble, and may die out, try to start it again, if it does not start, try one more time pouring a little gas in the carb, start it and everything should be ok

[old55pete]

Good point George, Or he can do like we do the race car after sitting all winter( we drain the carb out) put about a spray paint can cap full of gas and pour it down the bowl vent and fill up the float bowl, spin it over and let it run and let the system prime up while it is running on whats in the bowl.

Sorry............................DUAH

[86 1/2 Brutus]

Steve, exactly.  All that is going to happen is the battery is going to die trying to crank and prime that system.  especially after everything that has been changed.  

[Frank Wyatt]

I've had bugs build nests inside of open lines before. The first time that happened to me it drove me nuts trying to figure out why I could not get gas to the pump. It happened on the truck I have now also but having had this happen before, it did not take long to figure out. What surprised me was the line was not open for long before some bug thought he could move in.