Tractor starting issues

[greg_g]

it is a glow plug type thing in the manifold. fed by electricity, and fuel from the top of the injectors, and there is no fuel there. and it has never worked.

Thought so. Get that fixed, and your hard starting problems (and most of the white smoke) will be a thing of the past. Had to do that with my Yanmar a few years back, and was pleasantly surprised what an inexpensive fix it turned out too be.

Plus, you won't have to use the starting fluid anymore. I wouldn't be surprised if that contributed to your premature head gasket failure. If you've got any left though, it does a good job on cleaning old bar oil and sawdust out of chain saws.

//greg//

 

[whynot162]

I fixed it electrically, but I get no fuel out of the top of the injectors, So there is no fuel in there to preheat.
Is this all related? On my old 7.3 there was always fuel out of the fuel return.


The screen in the tank is clean, and I have to order a fuel filter, and will not get it until the end of the month. I replaced the o-ring in there with a normal o-ring, and I guess it is supposed to be a flat side for the canister to seal to, would that cause this issue? I am also going to replace all of the crush washers in the system. but the fuel is flowing clear and quick at the inlet to the lift pump, and there is nothing on the screen in the tank, or the float bowl.

 

[Bob Rooks]

I fixed it electrically, but I get no fuel out of the top of the injectors, So there is no fuel in there to preheat.

I just isn't plumbed correctly from the factory (it requires a small fuel reservoir and a solenoid valve). These are NOT unit type injectors so you won't get any fuel flow there, only leak off (that is until the pintle spring breaks and then only a few cc's at a time).

 

[whynot162]

ok, Is there a how to somewhere to set this up? It would be nice to have it work, and aid in the start.

 

[Bob Rooks]

ok, Is there a how to somewhere to set this up? It would be nice to have it work, and aid in the start.

Apparently the factory installation is incomplete, I can't help you there. Is there a solenoid valve attached to a small fuel reservoir above the level of the intake manifold?
A picture of your setup would be very helpful.

 

[whynot162]

I will try and get a photo,
But there is no valve or bowl, and the fuel line is connected to the top of the injectors, Nothing like you are talking about.

 

[greg_g]

I fixed it electrically, but I get no fuel out of the top of the injectors, So there is no fuel in there to preheat.

You typed "injectors" (plural). Please clarify. I ask, because a typical manifold heater has only one. And there are two types; my Yanmar had the little fuel bowl like Bob described. It relied upon gravity and intake vacuum to deliver fuel to a single manifold heat plug (as opposed to multiple cylinder glow plugs), and I had to fill it periodically by hand. The return line type also relies upon gravity, but not quite in the same way.

Your pump delivers fuel to the cylinders under high pressure, hence the steel lines. But what's delivered is more fuel than the cylinder needs for a single detonation. What's left after the individual injectors take what they need back to the fuel tank via those low pressure lines. So when the engine is running, fuel is always moving in a loop; low pressure to the pump, high pressure to the cylinders, low pressure back to the tank.

One of these low pressure lines is hooked up to the manifold heater plug. But note that it's not in the loop. Once it's full, fuel sits there waiting to be used when you need it for the cold start. You must manually activate the pre-heater either by keyswitch (HEAT position) or separate push button (keyswitch ON). This energizes the heat plug. Once it's hot enough, you turn the keyswitch to the START position. This creates intake vacuum, which in turn sucks fuel out of the return line and past the heater. It ignites, and pre-heats the air that is destined for the cylinders. The hot air mixes with the cold high pressure fuel, and - ideally - detonation occurs. The colder the ambient temperature, the longer you have to pre-heat. Occasionally it takes more than one pre-heat cycle.

Both manifold heaters and glow plug systems can also be re-energized while a cold engine is trying to get up to speed. Some systems call this "after-glow". When your engine has started - but is sputtering and not all cylinders have caught yet - turn the heater back on. Sucking more hot air into the cylinders helps cold cylinders catch up with those that are already detonating AND cuts down on the amount of white smoke that comes out the exhaust.

Oh yeah, and set your hand throttle at 50% or more prior to these cold starts. Once the engine catches, you can then decrease throttle as it warms up.

//greg//

 

[Bob Rooks]

Just to clarify:
These are NOT unit injectors that are found in these engines. There is no real return fuel from the top of them, they are common rail injectors that utilize a fuel injection pump. The return line comes from the fuel injection pump. Unit injectors do NOT have a separate fuel injection pump - it's built into the injector. These are unit injectors:
Unit Injector - Wikipedia, the free encyclopedia

That's why I stated the factory installation was incomplete.
I would contact Jinma and ask just how your system is supposed to work.

 

[whynot162]

mine sounds like it is set up like the 2nd one greg talks about, being fed from the fuel return from the top of the injectors, which there is no fuel there, due to the type of injector?

the tractor is a rhino, not a jinma, or are they the same thing? I have disconnected the wire to the preheat because after I got it to work electrically, it did not good, because there was no fuel, and it melted the fuel hose. So I decided better safe, since it did not work anyway. Even if not the same, the preheater should be similar enough to work?

the old 7.3 pre powerstroke, had retirn lines on them that always had fuel in them, and they were driven by a IP. that is what I was comparing it to.

Thanks again for the help, and I will get a photo on my next day off.

 

[greg_g]

I understand. Jinma uses individual glow plugs in swirl-chambers, one per cylinder. I used to own two of them. Your Rhino uses an intake manifold heater, one glow plug only. Just like my Yanmar.

That cheap Chinese rubber decomposes, the feed hose could have collapsed internally. Replace it with a section of good fuel line, prime the new line, reconnect the switch wire, try again.

//greg//