Won't Idle

[snowmansrx]

Hello I have An Argo vanguard with a briggs and Stratton 16hp vanguard motor That doesn't like to idle otherwise appears to run ok except for the brain fart that caused it to blow a head gasket 100% my fault. Back to my problem, I am new at working on Argo's but I have worked on snowmobiles and noticed that the drive belt an a sled doesn't turn at idle but does turn on my argo is this normal and if not coulld it cause it not to idle properly.

[Jeff t-boss]

No; and yes;. No, it shouldn't turn at idle, and yes, it could cuase your problem. If your belt is turning at idle, it could be any one of a few things, or a combination of them. 1; being that your idle is too high to start with, or 2; there is a clutch problem. Could be springs, counter-weights, binding, wrong clutch for application. (2 stroke clutch on 4 stroke motor, visa-versa; yes, there is a diffefence) 3; wrong belt and/or adjustment, 4; torque converter/final drive malfunction(s). If possible, remove the belt from the clutch, and set your idle on your engine. If I'm not mistaken, I believe it to be 900-1000RPMs. Check your books. Also pay attention to the gap at the point closest to the center of the clutch. (with the engine running). When you shut down the engine, the gap should not change. If it does, (It will get bigger) you have a clutch problem. If that all checks out OK, put your belt back on and make sure it is adjusted correctly. Again, check your books. Another way to do this is to move the motor as close to the torque converter/final drive as your mounting hole will allow, and then do a test run to check for slippage under load or at higher speeds. (You'll smell it!) I set my idle just alittle high, and adjust the belt till it just tries to start grabbing, then turn my idle down a hair. Engine will idle nice and smooth, and belt will not turn. Hope it helps....................Jeff

[Robio_8x8]

One symptom could be any number of things

Does it do it with the choke on ? does it do it in neutral?

Without seeing when is happened or under what conditions it is difficult to trouble shoot the problem. The Argo does engage the belt different then a snowmobile because most snowmobiles do not have reverse, neutral, forward low, forward high. Just forward.I find the Argo will engage the belt at a lower RPM then a sled .
As far as the engine idle start with the basic maintenance, fuel filter, oil & filter, plugs, test for spark on both cylinders, air filter. check the gas tank vent if it is plugged up.
Then check the compression of the engine with a compression tester to see if the two cylinders are equal. Air fuel mixture, fuel pressure, spark timing ( not sure myself how to do this on this engine yet )


I am having an odd issue that I have not looked into too deeply on my vanguard with the same motor were it will need to be chocked in ideal sometimes but it could just be old stale gas. When I run through the old gas I will look into it more if the problem doesn’t work it’s self out .

[Jeff t-boss]

Hey guys, I used to work in a small engine shop, and with your note I think you might be interested in the following. The Vanguards are notorious for condensation or water in the carb because the carb is located in the valley on top of the engine. because it gets that much warmer, and you are putting cool gas to it, it creates the ideal conditions for condensation/water in the carb. I cleaned/rebuilt many carbs because of this condition, and it always took care of those running problems.

[Robio_8x8]

Thank you for the tip

Hey guys, I used to work in a small engine shop, and with your note I think you might be interested in the following. The Vanguards are notorious for condensation or water in the carb because the carb is located in the valley on top of the engine. because it gets that much warmer, and you are putting cool gas to it, it creates the ideal conditions for condensation/water in the carb. I cleaned/rebuilt many carbs because of this condition, and it always took care of those running problems.

I was planning on fogging the engine but the problem seems to be going away as I use it and I think the guy I bought it from had it sitting for a couple of years, maybe more . It seems to be working its way out because it is happening less and less as I use the machine. I put some stabilizer in the gas when I got it and final I ran low enough to add new fresh gas.

[snowmansrx]

Thanks

Thank you for all your help I did clean the carb still doesn't idle corectly.

[Robio_8x8]

If your carb is clean and set up right

I would check if the compression is equal in both cylinders with a compression tester. then check the spark quality and timing
Spark should be blue not orange or yellow ( use extreme caution when doing this test, rubber gloves, insolated handles on tools safety glasses keep away from gas fumes etc.)

Check if the is vacuum at the fuel pump at ideal

[micmac]

Snowmax,

There is a wire that connects the the ignition magnetos on each cylinder. There is a diode on each end this keeps the ignition from firing at the same time. If one of these diodes go bad it might be the cause of the rough running idle.

Mike