I've got two questions about my carburetor.

[Mosinguy]

How do I remove the air cleaner stud out of my old carb and put it in the new one? And how do I adjust my carburetor correctly? It idles a little high and the engine runs a little bit after the ignition is turned off so it's running a bit rich. It's a Rochester Varajet II, or e2se.

 

[PwrCruz]

Are you just trying to remove the stud from the main body or is it broken off with nothing sticking out? If your just trying to remove the stud you can use a couple of jam nuts tightened against each other so you can crank on them. If its broken off your going to have to drill into the remaining part of the stud and use a easy out.
If you drill be careful not to drill all the way thru the stud and into the carb body.

 

[9mmfan]

Try adding two nuts to the air cleaner stud and 'jam' them together; may back out that way.
There should be an idle speed screw on the throttle shaft outside the carb. You should be able to look up the specified idle speed in a manual. The idle mixture is another story. I always did it by ear, so I don't know how to explain it to you.

 

[Indy 1911]

Are you guys speaking english. LOL -- Sorry. Son of a plumber.

 

[Mosinguy]

Just trying to remove the air cleaner stud. So put two nuts on the stud? My stud has two thread pitches on it so I do that on the bigger threads near the carb right? And if that removes the stud, what do I do to put the stud into my new carb?

 

[Dj15802]

Yes, tighten them against each other and then you should be able to thread the stud out.

 

[Mosinguy]

Try adding two nuts to the air cleaner stud and 'jam' them together; may back out that way.
There should be an idle speed screw on the throttle shaft outside the carb. You should be able to look up the specified idle speed in a manual. The idle mixture is another story. I always did it by ear, so I don't know how to explain it to you.

How do I adjust the mixture?

 

[Hohn]

You can use the jam nut trick or just grab the stud with water pump pliers and unscrew it. (some studs are pressed in, but very few). Grab it in a threaded area where buggering up the threads a bit won't cause a problem (grab low).

Carburetors have several adjustments, but only a few that are worth fiddling with. Different carbs have different levels of adjustability.

Since the varajet is an 'electronic carb' it is probably less adjustable than a regular carburetor.

When your turn off the ignition, the engine loses the ability to fire the spark plugs. That means that in order for it to keep running, there must be something hot enough inside the engine to light off some residual fuel that's leaked into the ports. This is usually some epic combustion chamber deposits that glow like embers while the engine is running. You are probably getting pretty bad mileage with the thing as its running.

If the plugs themselves were the wrong heat range, you wouldn't just have this run-on; it would also be pinging under load. That's why I think it is a really dirty chamber (piston crown and chamber deposits).

So for the run-on, I would recommend a good dose of really stout fuel system cleaner (like Seafoam). Dump some in the carb itself, but the rest in the fuel tank.


For the high idle, see if you can adjust the idle screw that sets the idle speed. Many of these electronic carbs have a "fast idle" solenoid that raises the idle speed for things like cold weather or air conditioning kicking in, etc. If this solenoid is failed, it can cause the high idle condition. If the solenoid works, then the screw should probably be adjusted so that "low idle" off the solenoid is about 700rpm and fast idle is whatever result from the full lift of the solenoid.

Adjust the idle mixture screws so that the engine runs smoothly when warm at both idle speeds. Generally, I alternately screw them in until the engine starts to stumble, then back them off 1/4 turn each. Idle mixture screws are only to adjust WARM idle mixture. Cold mixture is a function of choke, not idle mixture screws.

Hope this helps.

Justin

 

[Mosinguy]

You can use the jam nut trick or just grab the stud with water pump pliers and unscrew it. (some studs are pressed in, but very few). Grab it in a threaded area where buggering up the threads a bit won't cause a problem (grab low).

Carburetors have several adjustments, but only a few that are worth fiddling with. Different carbs have different levels of adjustability.

Since the varajet is an 'electronic carb' it is probably less adjustable than a regular carburetor.

When your turn off the ignition, the engine loses the ability to fire the spark plugs. That means that in order for it to keep running, there must be something hot enough inside the engine to light off some residual fuel that's leaked into the ports. This is usually some epic combustion chamber deposits that glow like embers while the engine is running. You are probably getting pretty bad mileage with the thing as its running.

If the plugs themselves were the wrong heat range, you wouldn't just have this run-on; it would also be pinging under load. That's why I think it is a really dirty chamber (piston crown and chamber deposits).

So for the run-on, I would recommend a good dose of really stout fuel system cleaner (like Seafoam). Dump some in the carb itself, but the rest in the fuel tank.


For the high idle, see if you can adjust the idle screw that sets the idle speed. Many of these electronic carbs have a "fast idle" solenoid that raises the idle speed for things like cold weather or air conditioning kicking in, etc. If this solenoid is failed, it can cause the high idle condition. If the solenoid works, then the screw should probably be adjusted so that "low idle" off the solenoid is about 700rpm and fast idle is whatever result from the full lift of the solenoid.

Adjust the idle mixture screws so that the engine runs smoothly when warm at both idle speeds. Generally, I alternately screw them in until the engine starts to stumble, then back them off 1/4 turn each. Idle mixture screws are only to adjust WARM idle mixture. Cold mixture is a function of choke, not idle mixture screws.

Hope this helps.

Justin

Would some Seafoam in the fuel and some of that spray Seafoam type stuff for intakes clean those deposits up?

 

[remauto1187]

Just lock a set of vice grips on the stud down towards the carb body. (Doesnt matter if you booger up some thread there). Then tighten down into rebuilt carb.

The engine having its idle adjustment too high WOULD cause the engine to continue to run when shutoff (dieseling). That carb being a E2SE tells me it is a electronic carb with idle mixture solenoid controlled by an ecm. DO NOT MESS WITH ANY MIXTURE ADJUSTMENTS! YOU WILL BREAK IT!
The idle can be adjusted at the throttle linkage. Look for a screw going up against a stop on the throttle arm. Back out the screw to turn the idle down.

 

[remauto1187]

If you do indeed have alot of carbon buildup the easiest way is to spray misted water into the top of the carb while the engine is warmed up and idling. DO NOT POUR WATER INTO THE ENGINE! Only mist! The water mist will super cool the carbon buildup and cause it to flake off then burn off some and end up in the exhaust stream. You might have to do this many many times to get good results. Easiest way to inspect is pull spark plugs and shine a flashlight down the hole while moving piston toward TDC.

 

[Mosinguy]

Just lock a set of vice grips on the stud down towards the carb body. (Doesnt matter if you booger up some thread there). Then tighten down into rebuilt carb.

The engine having its idle adjustment too high WOULD cause the engine to continue to run when shutoff (dieseling). That carb being a E2SE tells me it is a electronic carb with idle mixture solenoid controlled by an ecm. DO NOT MESS WITH ANY MIXTURE ADJUSTMENTS! YOU WILL BREAK IT!
The idle can be adjusted at the throttle linkage. Look for a screw going up against a stop on the throttle arm. Back out the screw to turn the idle down.

Well when it idles sometimes it'll sound like it wants to die but it never does. Is that because of those deposits or is my mixture too low? Or is there something up with my solenoid?

 

[remauto1187]

Well when it idles sometimes it'll sound like it wants to die but it never does. Is that because of those deposits or is my mixture too low? Or is there something up with my solenoid?

Look and test for the obvious first. Vacuum leak, fuel pressure, ignition timing, fuel filter, distributor cap/rotor and spark plug wires. Open hood up at night with no lights around you and see if you see any arcing around spark plug wires. KEEP YOUR FINGERS OUT OF THE FAN!

Spray starting fluid around intake manifold gasket sealing area and carb base gasket sealing area. If engine idles up briefly you just found a leak. (Do this with air cleaner installed on carb).

 

[Hohn]

Would some Seafoam in the fuel and some of that spray Seafoam type stuff for intakes clean those deposits up?

I would use an actual carb cleaner if you want to clean out the interior of the carb (Gumout).

Seafoam is for what's AFTER the carb: intake valves, piston rings, piston crown, chamber, etc.

H

 

[karl77]

rather than spray starting fluid (which can/will burn holes in aluminum pistons [personal experience]), I would use carb cleaner spray.

to properly adjust a manual carb, a vacuum gauge is needed.

 

[74J10]

I have always put seafoam in through the vacuum lines. Pull the brake booster line and stick it into the seafoam container JUST A LITTLE BIT. It will smoke like mad!!! It will pull the engine down and if you put too much in it will kill the engine, that's why you do it a little at a time. I would run a can through the vacuum lines and a can in the gas tank.
I believe that is the directions on the side of the can too. It works well, and fumigates for mosquitoes at the same time. The neighbors will love it....

As for adjusting the carb, I played and played with my old Eldebrock on my old Jeep and never could get it to run right so I pieced together a propane injection kit and put that on and it ran awesome!!!! Do you have a manual for the carb? If not, get online and find one. It will explain the idle adjustment screw and the other adjustments. I would just mess with the idle until you run the seafoam and get the engine cleaned up. Also check for vacuum leaks like said above. Fix all the other stuff, then fix the tune on the carb. Vacuum leaks can wreak havoc on tuning a motor.

Out of curiosity, what are you working on? Even though I don't know much about carbs, I love old iron.

 

[Mosinguy]

I have always put seafoam in through the vacuum lines. Pull the brake booster line and stick it into the seafoam container JUST A LITTLE BIT. It will smoke like mad!!! It will pull the engine down and if you put too much in it will kill the engine, that's why you do it a little at a time. I would run a can through the vacuum lines and a can in the gas tank.
I believe that is the directions on the side of the can too. It works well, and fumigates for mosquitoes at the same time. The neighbors will love it....

As for adjusting the carb, I played and played with my old Eldebrock on my old Jeep and never could get it to run right so I pieced together a propane injection kit and put that on and it ran awesome!!!! Do you have a manual for the carb? If not, get online and find one. It will explain the idle adjustment screw and the other adjustments. I would just mess with the idle until you run the seafoam and get the engine cleaned up. Also check for vacuum leaks like said above. Fix all the other stuff, then fix the tune on the carb. Vacuum leaks can wreak havoc on tuning a motor.

Out of curiosity, what are you working on? Even though I don't know much about carbs, I love old iron.

1984 S10 with the teeny tiny 2.0 engine.

 

[remauto1187]

rather than spray starting fluid (which can/will burn holes in aluminum pistons [personal experience]), I would use carb cleaner spray.

to properly adjust a manual carb, a vacuum gauge is needed.

Hmm Ive never burnt holes in any of my pistons....and Im 41 and Ive sprayed many engines. I also never attempted to adjust a ELECTRONIC FEEDBACK CARBURETOR that has a mixture control solenoid & TPS hooked up to an ECM either.(Why would you the computer adjusts it often) Ya know the first E in E2SE (Rockester series number of carb) denotes that it is an electronic control feedback carburetor...