Starting PROBLEM

paulBurns · Feb 19, 2005

YM3100----limited knowledge and experience

I cleaned the fuel filter bowl because of trash in the bottom.
Replaced bowl but did not fill just turned on fill valve. Could not start tractor. I then removed bowl filled it up and then replaced bowl--opened valve--bowl full. Could not crank.
The first time or two it did crank for a sec then go dead.
Thinking air might be in fuel system I opened lines from pump and turned engine over, each line pulsed a small amount of fuel each in turn. then I did the same thing at lines connected to injectors with the same little pulse of fuel when turning enjine over.
I charged battery and cleaned a couple of connections so that engine turns over rapidly but could not get it to crank. Then I looked closer and found small plastic fuel bowl ?? with a line to the air intake?? I opened the bowl and filled with fuel and tried again thinking this was a place to prime the system. No crank still.
I then rechecked the fuel lines where they connect to injectors --now there is no pulseing fuel.
Bottom line--I started with a good running tractor and after a little maintence on the fuel filter bowl I can't get it to hit a lick. BTW I did try it with the decompression pulled back. I also have not used it much in cooler weather. Now it is ablut 35-40 degree.
Any help for a newbie piddler who seems to be dangerous around machinery!!!!

Inspector507 · Feb 19, 2005

Not familiar with the 3100 but the smaller units have 3 bleed screws. 2 at the filter and 1 at the pump. Open the one closest to the inlet side of the filter and crank until no air comes out. Then move to the one at the outlet side of the filter and repeat. Then go to the one at the pump and repeat. I think on the smaller units it is a 10mm hex head with phillips slots as well.

normde2001 · Feb 19, 2005

"2 at the filter and 1 at the pump. Open the one closest to the inlet side of the filter and crank until no air comes out. Then move to the one at the outlet side of the filter and repeat. Then go to the one at the pump and repeat."

Correct on the bleed screws; however you shouldn't crank during this process, ( you will only draw air into the pump). Just open the bleed screws in sequence and let gravity remove the air until only fuel comes out. After bleeding the screw at the pump, attempt to start. If no go, you may have to repeat the process, or sometimes loosen line at the injectors and then crank the engine over, (this is usually not necessary).

paulBurns · Feb 19, 2005

Inspector and Norm you are both to be commended and thanked. The three screw bleeding method worked. I left the new battery on because it was time for a new one anyway.
I do have one other question.
What exactly does the PS pisition on the switch do. I did not even know it was there until today. Also what is the small plastic bowl with a line to the intake do.
I am learning slow but sure and thanks again guys.

mark777 · Feb 19, 2005

Paul,

The TS (PS) if indicated on the ignition switch, turns on the power to the igniter inside the intake manifold. The small plastic resivor under the hood holds fuel that feeds into the intake and ignites for cold start applications. The system is caled thermostart.

Hope this helps,

Regards Mark

Inspector507 · Feb 19, 2005

Norm,
Thanks for correcting me. I never had to do it when I had my Yanmar.

paulBurns · Feb 21, 2005

Mark thanks
What is the cold start procedure to use?
I assume
First fill the resevor with fuel.
Next turn to TS position and hold for some amount of time I assume the igniter warms the intake but cannot understand just how it is supposed to work. Thanks

Jagmandave · Feb 22, 2005

Since I had no manual or instructions when I got my Yanmar, I started mine very much the way I used to start old Mercedes car diesels, hold the ign key in the start position till the light goes out then kick in the clutch to start winding her over. Seems to start easily this way, of course I was always under the impression that by using this procedure I was warming the glow plugs, and only found out by researching this forum that it doesn't have glowplugs! Anyway, it doesn't seem too sensitive to format, as I also started it with minimal throttle opening too, and it always seems to fire right up. One thing I've noticed, having the throttle wide open on a cold start sure puts out a ton of smoke!

mark777 · Feb 22, 2005

Paul,

Most owners, dealers and suppliers agree that the throttle position should be opened 2/3, thermostart bowl fueled with enough fuel for 10 - 20 seconds, key full left, decompression handle pulled out and then key full right to start until the oil light/gauge indicates oil pressure. Release decompression handle and it starts.

Although I have the thermostart on most of the Yanmars, I have really never needed it where I am located. I just make sure they all operate normally.

Mark