Diesel Teck question

[phil25]

A general question, but is connected to a Landini/Japan diesel, which is hard to start.
Glow plugs have been changed, but still takes about 6 attempts to actually start, battery will give out first. I am thinking it would be normal that when the injector connection is undone, there will be fuel at the connection ready to be compressed, and pumped out with the very first roll of the engine? which leads me back to there is a air/leak down in the fuel lines or pump it self? Also I could break the lines at the pump discharge and intake for supply quantity.
Once started it is good for the day, but it does sit a week at least till the owner returns.
Can you offer any thought on this, I have not broken the injector connections yet, wanted to check on my line of thought first.
Tks

 

[Dieseltech]

Question, does the engine start right away then die after setting a week? If so then there's a chance fuel is getting away from the injection pump after setting awhile and it will start, then die when the air gets into the injection pump. If it does not start after setting, is there white exhaust smoke on the first start attempt? If compression is good and glow plugs work right it SHOULD start on the first try. Best way to bleed air from fuel system on glow plug engines is to loosen the injector line nuts and REMOVE the glow plugs. Now crank engine until fuel is at all injectors, tighten the line nuts, then crank until you see air/fuel mist blow out all glow plug holes, then you know fuel is getting into the pre chambers. Replace plugs, heat them and start engine. It MIGHT be hard starting because the plugs are not on long enough, or engine compression is lower than normal too.

 

[matthies]

Are the glow plugs getting power ? 12V

 

[phil25]

OK, The glow plugs are getting power and draw current, i forget what the readings were, and they are new just because. It doesn't start right away, takes about 6 attempts, and runs all day, does not die out, and re starts anytime after the first start. it sits at least a week or more, before being needed, depending on the owners schedule to be home.
I was trying to cheat a bit on the checking this and that by disconnecting the injector lines, no problem, i like the plan on removing the glows and fuel mist out first.
I don't recall any smoke at all when trying to start, and it just came to me there is a timer in the glow circuit, maybe adjustable? the tractor is 3 years old, probably a 100 hours+/- on it.
All good and will see what happens this weekend, and report back soon. Tks

 

[caterpillar guy]

If possible try to start it in about 2or3 days if the same problem you have a fuel leak off letting air in the system either through a gasket on a filter or return line or at a fitting if fuel hose it could be porous after all these years if an older machine.

 

[sotxbill]

bad connections at the glow plugs or bad glow plugs are common problems. Take a infrared heat gun and measure the temp at each glow plug after a 20 second glow cycle. They should each show heat, so hot that it will burn your fingers.. Also each glow plug should draw 4 to 10 amps apiece pending on fast glow or slow glow plug type. Plugs MUST get hot on cold start cycle!!! AND two or more plugs must work to make the engine try to start. All connections must be clean and tight, and switch must allow high current to flow! You can also measure the voltage at each glow plug during a heat cycle with a second person. SHould see at least 8 volts or more at each glow plug.. during a cycle. Measure only on the glow plug threaded tip, not on the wire itself.

 

[Nathan (SD)]

I agree. It should smoke black but not fire if it is a glow plug issue. No smoke means no fuel.