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choke lever inquiry briggs quatro


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10-14-14, 02:35 PM   #1  
choke lever inquiry briggs quatro

I acquired a lawnmower that runs fine but the lever as can be seen in this picture (the white-colored plastic lever sticking out there to which the ends of both of those springs are attached toward the top of the picture) does not move/spring toward the direction of the top of the picture when the choke/throttle lever on the other end of those springs is pushed to the right (toward the choke position). The springs look to be attached correctly, and I can indeed choke/start the engine when I manually push and hold the end of the white lever toward the direction of the top of the picture. Then after it starts and I let loose of the white lever and move the throttle lever to the left to the run position all is fine. Just confused/unclear about how to get that white lever to move up toward the top of the picture (to full choke position), as it seems it should, when the throttle lever is moved over to the right. The way it is now, as I tried to describe, when I move the throttle lever all the way to the right (choke position) the spring/mechanism isn't moving that white lever at all, as it seems it should be doing. Engine is a Briggs Stratton Quatro 4hp.


 
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10-14-14, 03:59 PM   #2  
Since the engine has a primer it doesn't have a choke, usually when there is no throttle cable attached the smaller tab on the right is bent down to hold the linkage in place. Have a good one. Geo

 
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10-14-14, 04:37 PM   #3  
Okay geo thanks. I do indeed see this mower/engine is called a "throttle-free" design. Any type of indicator (a sticker maybe with words/arrows) below/around the big black lever to which the two springs are attached that I might expect to indicate which direction to move that lever for "run" or "stop" seems to be missing. So when I move that black lever to the left or right, I'm not sure which way is stop but I'm pretty sure (but could be wrong) it would be all the way to the left? Plus, I'm still lost about your mention of the smaller tab on the right needing to be bent down to hold the linkage in place. If possible could you try to clarify that for me please? I just know that the way things are now, to start the engine I need to prime the bulb, then move manually move/hold that white lever up to its position as far as it goes toward the top of the picture, then I can release that lever and push it back a little and then the linkage/lever/springs seem to be in the regular "run" position then, where it runs at normal operating speed.

Edit: After googling a little, I discovered what that white plastic lever is. Apparently I have an air vane governor and that looped link connected to the white plastic air vane comes from under the shroud and to the carb. Still confused about why/how the only way it will start is when I manually hold that air vane lever toward the top of the picture.


Last edited by sgull; 10-14-14 at 05:26 PM. Reason: additional info
 
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10-14-14, 07:08 PM   #4  
On this type of carb you should be able to see the primer shoot fuel into the engine if not then there is a problem with the priming circuit or diaphragm. There is no reason to move the throttle linkage to start id everything else is in order. Refer to the front top tab in the pic below for which tab to bend. Have a good one. Geo


 
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10-14-14, 09:15 PM   #5  
Yes I'm observing a good strong fuel shoot into the engine as you describe when I push the primer button, so no problem in that regard. I'll go ahead and bend that tab down on mine. Not sure why it's not already bent down, if that's the way it is supposed to be. But I'll go ahead and bend that down and see if that somehow helps. Thanks again.

 
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10-14-14, 09:29 PM   #6  
Bending the tab won't make a difference in whether it starts or not, but it should hold the throttle in it's fixed position. The lever is the governor arm and it controls the throttle on the carb, depending on engine speed. If the primer is shooting gas into the throat, 3 or 4 pumps of it should get it running as long as the throttle is wide open. If not, there is some kind of other problem.


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10-14-14, 09:46 PM   #7  
3 or four pumps of the primer does get it running, and it stays running nicely after that. But as I've been trying to describe it will only start (after the priming) when I move manually move/position that lever in the direction toward the top of my photo (and it's just a short distance, maybe 3/8" or so). Then when I let go of that lever after it starts, the spring(s) action pulls it back again a short distance, where it seems to stay as the engine then runs at operating speed. If I don't manually move/position that lever as I just described, it will not start.

 
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10-15-14, 01:18 AM   #8  
That is closing the throttle if you are holding the governor vane in that position. Generally an engine that isn't getting much fuel will start better with the throttle closed, rather than open. Try priming it a few more times and see if it starts at full throttle.


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10-15-14, 12:34 PM   #9  
Try priming it a few more times and see if it starts at full throttle.
Okay, I tried priming it six times times, rather than three or four like I had been before. I noticed on the last two or three pumps that the fuel seemed to squirt out in a stronger/heavier stream than the the first few. Then it started up without me having to hold anything manually down there. So it seems it just needed a little more priming. I was hesitant to prime it too much before, worried that would just flood it.

As far as the throttle control and spring business and governor vane situation, it seems like when I move that throttle control back and forth it doesn't affect/move the governor vane lever, in fact visually it doesn't look like it moves much of anything, as I'm trying to show in this video I took of it: http://vid207.photobucket.com/albums...psfjtq73cp.mp4
Although I did notice too that when the engine is running, I can speed it up quite significantly by manually pushing that governor vane lever back the other way. I guess that's the way it's supposed to be? Any further comment appreciated and thanks again.

 
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10-15-14, 12:49 PM   #10  
When the engine is stopped the linkage is in wide open throttle(WOT) position, when the engine starts the air from the spinning flywheel fins push against the governor vane and moves the linkage to slow the engine, as the engine is put under load the engine slows so the amount of air flowing to the governor vane is less letting it move forward which in turn increases the throttle in an attempt to keep the RPMs steady. Have a good one. Geo

 
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10-15-14, 01:16 PM   #11  
I see. Thanks geo for explaining. I've never had any past experience that I can recall in using an engine with this design. The mower was a give-away and it seems now all I need is to clean things up good, probably sharpen the blade, etc, and I might end up getting some decent service out of it for who knows how long. The lady giving it away said she got tired of having to pull on it so much to get it going, I think she said something about having to prime it about ten times too but I wasn't paying too much attention. At least I found so far if I prime it about six times it seems to start right up with just a pull or two.
Thanks again geo, and thanks cheese too.

 
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10-16-14, 11:23 AM   #12  
proper off-season storage?

Now that I've determined this mower seems to be in decent running shape, I'm wanting to go ahead and store it for the winter. I drained what gas was already in the tank (probably not very fresh gas, and no idea if any stabilizer added) and am considering putting fresh gas with Sea Foam treatment mix (2 oz Seafoam per gal gas ratio for stabilizer) into the tank and letting that run through the fuel system. My question is in regard to whether it's better to leave the tank full of the stabilizer-treated fresh gas in the tank (and within the carb) until next mowing season, or try to completely empty the carb and tank and leave the fuel system “dry” instead.

Also, I have an aerosol can of the Sea Foam brand “Deep Creep” which I think wouldn't be a bad idea to maybe spray into the carb throat and run the engine for at least a short time, maybe just prior to the winter storage?

Any comment/recommendations in regard to a good approach per my inquiries above would be greatly appreciated! Thanks.

 
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10-16-14, 12:47 PM   #13  
You will get a lot of opinions on that, I treat all my fuel with stabil so if I am going to use it within a few months I do nothing, if it is going to set for over a year I run it dry. Have a good one. Geo

 
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10-16-14, 01:16 PM   #14  
Well I figure it's going to set for about 8 months. If I just run it dry does that pretty much clear out any gas in the carb too, and not leave enough gas residue or whatever in there to harm/ruin the carb internals?

 
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10-16-14, 03:49 PM   #15  
Also I'm wanting to remove the blade to inspect/sharpen or maybe replace it. But I understand that before removing the blade it's best practice to drain the gas tank first (before tipping/tilting the mower up for adequate access). Is there any problem with running the mower engine with the blade removed? Because I want to go ahead now and run the fresh gas w/stabilizer through the system and then probably just leave the tank/system full of that gas for the storage period. But since I've already drained the gas tank and it's empty now I'd like to tip up the the mower now and get that blade removed, and it may take me a good while to get around to either sharpening it or obtaining a replacement. But meanwhile I wanna make sure to get some fresh gas/stabilizer into the system instead of leaving it empty long enough to where old gas residue might have a chance to gum things. Long story short, can I run the engine with the blade removed for a while and not worry about it or does that throw it off balance and potentially harm the engine or maybe prevent me from being able to start it with the blade off?

 
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10-16-14, 04:41 PM   #16  
The blade acts as the flywheel for the engine, it can be started without it, however the engine may kick back when you pull the rope, anytime you tilt the mower make sure the carb is up, if not oil and fuel can enter the carb and things get messy. Have a good one. Geo

 
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10-16-14, 05:58 PM   #17  
Ok geo, Think I'll opt for not starting it with the blade removed. Will just put some in some fresh gas/stabilizer, let it run until it runs out of gas, then siphon/suction what little remains out of the tank, drain the old oil out, remove the blade and also do some cleanup on the underside of the mower, and if it looks like it might be a while until I can replace the blade then go ahead and refill the tank with the fresh gas and stabilizer for now. Then when I eventually get around to replacing the blade and need to tilt the mower up again, drain the gas out again before I do that.

 
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10-17-14, 01:31 PM   #18  
With minimal experience sharpening a mower blade, I could use some advice with that too. I read a little about it and one recommendation was to attempt to stay with the same angle as was already there from the factory, and another recommendation was that typically I want to have a 40 to 45 degree angle between the sharpened edge and the flat part of the blade. I tried taking a picture by myself of me holding the blade and a square in a vice with a file but obviously I screwed up and was holding the square upside down here, but anyway is this the proper approach otherwise?


 
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10-21-14, 10:09 AM   #19  
My last inquiry here (previous post this thread in regard to sharpening the mower blade) is off-subject from the topic I started in regard to choke lever inquiry, so perhaps I should refrain from asking/discussing that under the topic. Although I am still awaiting any comment on it. Anyone? thanks

edit: Never mind. I just went this route: https://www.youtube.com/watch?v=_mwK4q-0rGA


Last edited by sgull; 10-21-14 at 12:24 PM.
 
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10-21-14, 12:24 PM   #20  
Here is a video. Have a good one. Geo
https://www.youtube.com/watch?v=eXLygHF6El4

 
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10-21-14, 01:03 PM   #21  
thanks geo. yeah I recall watching that one too already. thanks. have a good one.

 
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