Yanmar 3TNE74

[absaroke]

My JD 4100 has a Yanmar 3TNE74 with 750 hours. It used to start instantly but now takes several trys. I have the throttle at half, battery cranks strong, lots of black smoke out the exhaust. I cranks several times and it eventually starts. I have replaced the fuel filter and the fuel appears clean. I'm ready to drain the fuel tank and put in fresh fuel. I have a 55 gallon tank that lasts the season but maybe the fuel went bad.

Does this engine have glow plugs? The manual doesn't list any.

 

[rsewill]

Welcome to TBN.

Yes, it has glow plugs, just no glow plug indicator light. The glow plugs activate simultaneously with the starter being engaged. You can activate the glow plugs before engaging the starter by pulling out the yellow PTO button, then turning the key to the starter position for about ten seconds, then pushing the PTO button in and cranking the starter. That should take care of much of the smoking at start-up.

Ron

My JD 4100 has a Yanmar 3TNE74 with 750 hours. It used to start instantly but now takes several trys. I have the throttle at half, battery cranks strong, lots of black smoke out the exhaust. I cranks several times and it eventually starts. I have replaced the fuel filter and the fuel appears clean. I'm ready to drain the fuel tank and put in fresh fuel. I have a 55 gallon tank that lasts the season but maybe the fuel went bad.

Does this engine have glow plugs? The manual doesn't list any.

 

[absaroke]

Ron - thanks for the info. I called the dealer the next day as well. I drained the fuel tank and put in fresh fuel. As you suggested, I pulled out the PTO and turned the key for about 10 seconds. Still didn't start as easily as it once did. Do you or anyone else have drawings as to remove and test the glow plugs? That's the next area I will investigate.

Thanks, Mike

 

[beenthere]

Mike
jdparts lists the glow plugs as part # AT110814

Shown here as item #28

 

[Wichman]

My JD 855 had similar problem. Just got harder and harder to start. Bad news I had to rebuild the engine. Seems that the air filter is not up to needed on these. I now have a quick starting tractor with a two stage air filter and a much lighter pocket book.

 

[gjsnow]

I'm not sure this will help but a thought.
I have a 3TNE88 36hp motor. I had starting issue and after months of replacing fuel lines, putting in check valves, it turned out to be a bad fuel shut off solenoid. When I tried to start the engine, it just would seem like it wasn't getting fuel.
Now it starts up on the first time, every time. (I hope I just didn't jinx myself.)
By the way, Always connect your battery to a battery tender to keep it topped off all the time, especially if you are having starting issues.
GJSnow.