Yanmar ym155d won't start

[Bthieman]

Hi all, hope you have ideas
I bought this 2 cyl. diesel tractor due to its small size and its loader
The guy said he had it running by pushing it with another tractor, and said it probably needs a full engine rebuild ( I hope not). It has 800 hrs on the meter.
I bled the 3 screws and the injectors. It delivers dribbles of fuel. I have ordered new injectors, and a glow plug (it has a hole for one but no glow).
1. should I try to inspect the injector pump?
2. Is the glow plug needed?
3. Any source for another injector pump?
4. Any advice for this 70 yr old would be appreciated-the tractor is the talk of the family and I would like to post a pic of this beauty running

 

[Briana03]

Welcome to TractorByNet!

I moved your thread to the Yanmar forum.

 

[Scotty Dive]

Welcome!

So with pushing it runs so that's a good thing. Does the starter work? If it runs and you are getting fuel to the injectors than I am not sure the pump or injectors are the problem. So here is the bleeding instructions: Yanmar Tractor Fuel Bleeding Procedure

There should be a decompression cable pull (mine is on the left side of my steering wheel) that allows the starter to spin the tractor until you have oil pressure and the flywheel is spinning. Release that and the engine begins to catch. Throttle should be set at half.

The Yanmars do not have glow plugs but have an optional thermostart system that drips diesel over a heated coil warming the intake air when the ignition swtich is held to the CCW (left) before engaging the starter - When really cold I usually let it heat up for 45 seconds or more. You know if you have one if you have a plastic cup attached to the side of the block/valve cover. Not a great picture but here is a hoye image of one: Yanmar Tractor Parts: THERMOSTART TANK_

The YM115D is a domestically produced Yanmar tractor and there are US manuals available for it as well. Yanmar YM155D Shop Manual Tractor Parts

Let us know more about your starting issues, TONs of good knowledge here

 

[winston1]

If the gentleman you purchased it from was having to pull it to crank that would be a good indication it has low compression. The 800 hours on the meter could be 1800 or 2800 hours. Hope you haven't wasted your money on injectors and I would sure hold up on buying an injector pump. Not likely to be your problem. Assuming you can pull it and get it cranked. If so, watch the crankcase vent and see what kind of blow by it has. Here is an example of what you don't want to see. It is indicating and overhaul. Yanmar 155D Crankcase Vent - YouTube

 

[Bthieman]

HI Scotty
I agree this tractobynet is fantastic, I have read over 100 posts and enjoyed every one.
Thanks for the suggestions
I have since purchased 3 manuals on the Yanmar 155d (parts, service, and operation), as well as a couple 'diesel' manuals. After purchasing 2 injectors (from Hoye), I checked the compression- it is good a 340 each. I then tried to time it by changing shims and found that the delivery from the pump was low. I sent it to be rebuilt and will install it in a week when I get back to my cabin in Northern CA. I love learning about diesels and the fun of the rebuild ( My son has a diesel truck in Alaska and has been a great help). At age 70 I am finally in a position to have a tractor and learn about diesels. Thanks for the post
Grandpa Bill

 

[kenmac]

Welcome :welcome: to the Yanmar forum Grandpa Bill

 

[winston1]

Note this. What Should My Compression In PSI Be? What does your manual say it should be?

 

[Neat 1500]

340 is too low, should be up around 500 at a guess for a diesel.