Not sure I am really going to try to remove any kind of press fit jet.
The problem of recent is with engine not going back to idle speed when throttle up an back down again. What then happens is it is causing bike to try to move slow and have to hold brakes about 5 seconds till idle is slowed to minimum around 1750 rpm.
=========================================
carb parts pictures disassembled and assembled:
http://outdoorpowerinfo.com/repairs/...o_lms_carb.asp
http://www.mfgsupply.com/22-14111-br...on-498170.html
http://www.amazon.com/Briggs-Stratto.../dp/B0038U3I6C
Above are links to the carb that I have on my Briggs 80202 0430 3hp 4stroke side shaft engine.
It's not the carb that came with the engine as from the flea market it had no carb and I fixed up the engine and got this 498170 carb on Briggs and Stratton Engine.
It works fine and idles nice even without the governor on it. I would have kept the governor on it but the elbow 90 degree bend I used on the intake manifold made it a rather difficult task if I were to try. One thought was to use electronic sensors and servo motors to make the connection as they go around corners without bending.
Anyway what I did do was I put low throttle adjust and also high speed throttle adjust screws added to my carb linkages and it is working quite nice with the twist grip throttle.
Here is the problem if I can call it that. When I start the engine and it is idling nice and slow probably around 1750 rpm, the centrifugal clutch is doing fine being like in neutral and the bike does not need you to hold onto the brake levers when on level ground.
The clutch is supposed to be starting engaging at between 2000 rpm and at 2200 rpm be fully engaged which I suppose it does fine. The 1750 rpm idle speed is what the engine does when first starting the engine, but when you give it throttle to accelerate and maintain speed and then decide to come to a stop, it does not drop down to idle speed as fast as I would like.
I have stopped the bike and found after a second or so taking my hands off the hand brakes the motor bike is moving forward slowly as the idle is not dropped all the way down to its slowest speed like when I started the engine.
Note that the range of throttle position is fully at its minimum but needs as much as maybe 5 to 7 seconds when this happens if I don’t want the bike moving forward slowly.
This inexpensive carb has no low speed idle needle valve adjust or high speed needle valve adjust.
Inside the carb bowl is a part that serves as a nut to hold the bowl in place and also integral fuel passage way that I understand must do some kind of metering the fuel. You can see the picture in the attached link for the web page above for the #5 and #6 pictures.
Additionally there is picture #7 showing the main nozzle that goes up a center post to the venturi. That also must be metering the fuel as well.
If I knew if the main nozzle could be removed and replace with possibly a smaller one just enough to allow the carb with my engine to return to idle that much quicker from an above idle speed, I think I would like to try that.
I hope it would not have too much adverse effect on the range of speed up to max throttle as it is now. I think it would to some degree also make high speed max somewhat lower but not that much and I think that would be OK.
Only other way not needing very much in specialized parts or tools would be if I made a copper sheet cut out and put it where the gasket goes either right at the engine intake or between the carb and the intake manifold elbow. The part would include a second gasket so it would not leak and also make the diameter of the intake slightly smaller.
The smaller amount of volume of fuel air mixture would maybe equate to a lower idle if it does not stall it out all together.
I think this would be easiest, but if for this carb I could find a main nozzle that fits and can be installed with original removed without too much cost and specialized tool cost I could go that route as well.
Any help with this kind of thing?
I know cars with automatic transmissions have this happening all the time it seems as people keep inching up when the take their foot off the brake when at a stop light, right?
MT
PS:
I looked at other stuff online and hear press fit jets and nozzles may be removed with drift punch.
There also may be a washer or something and something else whatever that is which covers the jet or nozzle and you remove that first. Punching it through with a press or soft mallet carefully and it comes out the other side hopefully in one piece and could be reused later if not damaged.
Then a new part with different size can be reinstalled. More detailed info for my specific carb, the guy from Briggs on the phone discouraged any changing or working on jet parts and was no help other than saying it should work with my engine.
It does quite well, but the drop down to idle takes too long.
The original carb is a vacu-jet carb and uses jets that are with a screwdriver slot and screw threads. I have cleaned them quite easily. I have hear of using wood tooth pick so not to scratch parts and recently sounds good too, using monofilament fishing line.
Last I think maybe the use of the elbow 90 degree bend to fit carb to engine in tight fit on frame may be having effect on the slow response to going back to idle speed? It came off a lawn mower that really does not need any quick response to get back to idle. I'll check with others that extended the intake, especially if on a Briggs engine like mine. I know I have seen them on this site.
The problem of recent is with engine not going back to idle speed when throttle up an back down again. What then happens is it is causing bike to try to move slow and have to hold brakes about 5 seconds till idle is slowed to minimum around 1750 rpm.
=========================================
carb parts pictures disassembled and assembled:
http://outdoorpowerinfo.com/repairs/...o_lms_carb.asp
http://www.mfgsupply.com/22-14111-br...on-498170.html
http://www.amazon.com/Briggs-Stratto.../dp/B0038U3I6C
Above are links to the carb that I have on my Briggs 80202 0430 3hp 4stroke side shaft engine.
It's not the carb that came with the engine as from the flea market it had no carb and I fixed up the engine and got this 498170 carb on Briggs and Stratton Engine.
It works fine and idles nice even without the governor on it. I would have kept the governor on it but the elbow 90 degree bend I used on the intake manifold made it a rather difficult task if I were to try. One thought was to use electronic sensors and servo motors to make the connection as they go around corners without bending.
Anyway what I did do was I put low throttle adjust and also high speed throttle adjust screws added to my carb linkages and it is working quite nice with the twist grip throttle.
Here is the problem if I can call it that. When I start the engine and it is idling nice and slow probably around 1750 rpm, the centrifugal clutch is doing fine being like in neutral and the bike does not need you to hold onto the brake levers when on level ground.
The clutch is supposed to be starting engaging at between 2000 rpm and at 2200 rpm be fully engaged which I suppose it does fine. The 1750 rpm idle speed is what the engine does when first starting the engine, but when you give it throttle to accelerate and maintain speed and then decide to come to a stop, it does not drop down to idle speed as fast as I would like.
I have stopped the bike and found after a second or so taking my hands off the hand brakes the motor bike is moving forward slowly as the idle is not dropped all the way down to its slowest speed like when I started the engine.
Note that the range of throttle position is fully at its minimum but needs as much as maybe 5 to 7 seconds when this happens if I don’t want the bike moving forward slowly.
This inexpensive carb has no low speed idle needle valve adjust or high speed needle valve adjust.
Inside the carb bowl is a part that serves as a nut to hold the bowl in place and also integral fuel passage way that I understand must do some kind of metering the fuel. You can see the picture in the attached link for the web page above for the #5 and #6 pictures.
Additionally there is picture #7 showing the main nozzle that goes up a center post to the venturi. That also must be metering the fuel as well.
If I knew if the main nozzle could be removed and replace with possibly a smaller one just enough to allow the carb with my engine to return to idle that much quicker from an above idle speed, I think I would like to try that.
I hope it would not have too much adverse effect on the range of speed up to max throttle as it is now. I think it would to some degree also make high speed max somewhat lower but not that much and I think that would be OK.
Only other way not needing very much in specialized parts or tools would be if I made a copper sheet cut out and put it where the gasket goes either right at the engine intake or between the carb and the intake manifold elbow. The part would include a second gasket so it would not leak and also make the diameter of the intake slightly smaller.
The smaller amount of volume of fuel air mixture would maybe equate to a lower idle if it does not stall it out all together.
I think this would be easiest, but if for this carb I could find a main nozzle that fits and can be installed with original removed without too much cost and specialized tool cost I could go that route as well.
Any help with this kind of thing?
I know cars with automatic transmissions have this happening all the time it seems as people keep inching up when the take their foot off the brake when at a stop light, right?
MT
PS:
I looked at other stuff online and hear press fit jets and nozzles may be removed with drift punch.
There also may be a washer or something and something else whatever that is which covers the jet or nozzle and you remove that first. Punching it through with a press or soft mallet carefully and it comes out the other side hopefully in one piece and could be reused later if not damaged.
Then a new part with different size can be reinstalled. More detailed info for my specific carb, the guy from Briggs on the phone discouraged any changing or working on jet parts and was no help other than saying it should work with my engine.
It does quite well, but the drop down to idle takes too long.
The original carb is a vacu-jet carb and uses jets that are with a screwdriver slot and screw threads. I have cleaned them quite easily. I have hear of using wood tooth pick so not to scratch parts and recently sounds good too, using monofilament fishing line.
Last I think maybe the use of the elbow 90 degree bend to fit carb to engine in tight fit on frame may be having effect on the slow response to going back to idle speed? It came off a lawn mower that really does not need any quick response to get back to idle. I'll check with others that extended the intake, especially if on a Briggs engine like mine. I know I have seen them on this site.
