Deutz Agrolux 60 (SAME 1000 engine) problems

[Wisconsonian]

Try slacking off the fuel pipes at each injector in turn while it is running to see if you can identify a faulty injector or cylinder.

this is harder to tell the difference on a three cylinder than a six cylinder, unless the cylinder is completely dead, but I don't think the cylinder has lost enough power to notice easily.

Sure seems like the air was not the issue if it's gone and the problem remains.

What temp is the engine? how long has it ran or worked hard since the cold day the problem started? The video looks like there could be some wax remaining just as the bubbles clear. If the fuel waxed out when it was cold, and it hasn't been run up to operating temp to get the fuel warmed, then the wax can remain even at higher temps than it takes to form. Wax might drop out of fuel at 10F but not melt back into the fuel until 50F, just guesses, not exact numbers.

Have you confirmed fuel pressure when it's misfiring? or just idling? The other issue the injectors you cleaned, could have been a simple temporary problem, and now there's an injector problem we wouldn't expect.

 

[Andy FitzGibbon]

Only checked fuel pressure at idle, but will hook it back up and see if there's any change when the engine starts running rough. Haven't worked the tractor very hard since the problem started (just pushing a little snow is all) but I've been keeping it in the heated shop at about 60 degrees. I'm going to pick up more diesel today and try swapping the fuel out, just to see if maybe that's a factor.

 

[Wisconsonian]

OK, forget the wax if it's that warm. I'd check the pressure before swapping the fuel out.

 

[Andy FitzGibbon]

No time to work on it yesterday. I assembled a better pressure testing setup today, putting the gauge inline (with a snubber) between the lift pump output and the main fuel filter. 4-5 PSI at idle, 25 or so at PTO speed. Any change in pressure when it starts to smoke and run rough is very small (maybe 1 psi) and is probably due to the engine speed dipping slightly when the rough running starts.

I realized that "running rough" might not be the best description for what it does. It starts blowing white fuel smoke, there's an occasional stumble, but the biggest change is that the RPMs dip slightly and it loses the characteristic "knock" of a direct injected diesel. Kinda starts to sound like a gas engine, for lack of a better comparison.

I also reassembled the separator without the mesh filter cartridge (just the empty bowl) and the bubbles there all but disappeared. I'm wondering now if the bubbling seen there wasn't an air leak, but caused by cavitation from where the fuel enters the unit and immediately splashes against the top of the filter (which is solid).

Onwards and upwards... fortunately I don't need to use the thing urgently!

 

[box]

I was meant to start my one up and see what it looks like in the fuel bowl with the engine running.

Blocked/restricted exhaust? Muffler baffle collapsed? Birds nest? Stranger things have happened. I'm assuming you don't have EGR, a DPF or a cat?

Pull the muffler and exhaust manifold off, atleast it'll tell you which cylinder is the problem one.

Make a couple more videos while you're sitting on the seat so we can see the rev counter, it's hard to see or hear anything with the camera so close to the engine. Maybe show us what the exhaust is doing too.

 

[H200GT]

No time to work on it yesterday. I assembled a better pressure testing setup today, putting the gauge inline (with a snubber) between the lift pump output and the main fuel filter. 4-5 PSI at idle, 25 or so at PTO speed. Any change in pressure when it starts to smoke and run rough is very small (maybe 1 psi) and is probably due to the engine speed dipping slightly when the rough running starts.

I realized that "running rough" might not be the best description for what it does. It starts blowing white fuel smoke, there's an occasional stumble, but the biggest change is that the RPMs dip slightly and it loses the characteristic "knock" of a direct injected diesel. Kinda starts to sound like a gas engine, for lack of a better comparison.

I also reassembled the separator without the mesh filter cartridge (just the empty bowl) and the bubbles there all but disappeared. I'm wondering now if the bubbling seen there wasn't an air leak, but caused by cavitation from where the fuel enters the unit and immediately splashes against the top of the filter (which is solid).

Onwards and upwards... fortunately I don't need to use the thing urgently!

In the past I have found that both previous the Lamborghini and Deutz Agroplus that my brother still has always gave the impression that there was air in the separator bowl towards the top of the glass, but neither ever gave any trouble. I always put it down to cavitation, but your bowl does look to have more “cavitation“ than any i have seen, and looks to be more like air as the bubbles travel down the side of the bowl.

Fuel wise only issue I had really with ether was perished pipes back to the tank. The mechanical governor on the Agroplus had to be repaired as well at one point, but symptoms there was that it would not open out to full revs.

Not familiar with later engines, but if it has a hand priming pump I would also try bypassing that, seen them give trouble on many engine over the years

 

[2wheels]

could it be the injection pump? a bit worn and the timing moving?

 

[Andy FitzGibbon]

I was meant to start my one up and see what it looks like in the fuel bowl with the engine running.

Blocked/restricted exhaust? Muffler baffle collapsed? Birds nest? Stranger things have happened. I'm assuming you don't have EGR, a DPF or a cat?

Pull the muffler and exhaust manifold off, atleast it'll tell you which cylinder is the problem one.

Make a couple more videos while you're sitting on the seat so we can see the rev counter, it's hard to see or hear anything with the camera so close to the engine. Maybe show us what the exhaust is doing too.

Couple more videos. There's white smoke right from the start in the exhaust one, because its 20 degrees F outside. But you can see at 0:28 where the engine speed dips and it starts the white fuel smoke.

Same in this one, of the tach... you can see where the engine speed dips at 0:28. Also note that after throttling down at 0:42 it hovers around 600 RPM for a few seconds before dropping to normal idle. I hadn't noticed it doing that before the trouble started, but I also wasn't paying such minute attention to how it ran when it was working all right.

No DPF, catalyst or EGR. There's a crankcase ventilator system that I should investigate, just to make sure there isnt a massive amount of blow-by, but the symptoms dont really seem right for that.

Going away this week end and won't have any time to fool with it, but further ideas are welcome.

 

[Andy FitzGibbon]

Reading back over this, I notice that the rough running commences at 0:28 in both videos... I didn't plan that.

 

[Mur Huwcun]

Never knew they had a stop solenoid setup like that, all this end would stop from the governor abd move pumps over to excess fuel ready for next startup. Personally I woukd start again from tank, check every flexi pioe joint, remove and check all banjos and REPLACE every 14mm copper washers on the banjos. Assemble them loosly and blow them out with airline before nipping up. I’d even be tempted to blow back from lift pump to tank before anything else. The glass bowls will never be full when running. You coukd even rig a tank up on bonnet higher than engine to try, that would eliminate if it is an air leak in suction side

 

[Deerefarmer]

Watching the exhaust it would almost appear to be a timing issue ....

 

[H200GT]

It does seem to be a fuel issue from the video. However its not unknown for 4 cylinder engine to blow the head gasket, and its almost always between no4 and the water jacket. That gives similar symptoms, white smoke, but will also pressure the cooling system if its as bad as the one i did a few years ago now

 

[Andy FitzGibbon]

It does seem to be a fuel issue from the video. However its not unknown for 4 cylinder engine to blow the head gasket, and its almost always between no4 and the water jacket. That gives similar symptoms, white smoke, but will also pressure the cooling system if its as bad as the one i did a few years ago now

It's a 3 cylinder. The white smoke is definitely fuel (burns your eyes). I pressure tested the cooling system and the only leak I could find was a very very minor weep around one of the copper injector bushes. No signs of combustion in the coolant, or coolant in the oil.

 

[Andy FitzGibbon]

Watching the exhaust it would almost appear to be a timing issue ....

That's what I'm thinking too. My only other thought was that maybe a leaking injector is flooding a cylinder at higher RPMs.

Timing could be a governor fault, or low pressure at a pump, or a faulty injector... anything I'm missing? I don't see how it could have jumped time entirely, as it runs fine when idling.

 

[Deerefarmer]

Can you tell if there is a check valve on the fuel return line between injectors and the pump/s?

If yes try taking it out and give it a thorough cleaning.

 

[Andy FitzGibbon]

Can you tell if there is a check valve on the fuel return line between injectors and the pump/s?

If yes try taking it out and give it a thorough cleaning.

There's no return line from the injectors. Fuel returns to the tank right from the pumps, with a check valve in that line. The valve seemed to be working properly when I blew through it. I replaced the return hose when I did the main hose, as they both run in the same hard-to-reach place between the tank and firewall.

 

[ridger]

I had one of those engines seize once, went to look for a used engine and there was one for sale which wasn't running right, I didn't buy it obviously but heard later that it was some camshaft fault

 

[Andy FitzGibbon]

Sorry, I've neglected this thread, and the Deutz as well... had other stuff to attend to and needed a break from a project that has so far made no progress. I'm planning to test the fuel pressure post-filter, and also insert some clear line to see if the lift pump is producing any air. I'll also pull the pump and injector lines and make sure they aren't blocked. Beyond that, it may have to go to someone with the right tools (injector tester, pump timing equipment) to further diagnose. I appreciate everyone's contributions!

 

[box]

I was just thinking about you today and wondering how you were getting on. I was standing next to my running SAME which has the same glass filter bowl (and the same lift pump), my glass bowl didn't have any air bubbles/cavitation like your one does, it just had one big "bubble" at the top which arrives when the engine is running and stays there until it's turned off.

 

[Andy FitzGibbon]

I was just thinking about you today and wondering how you were getting on. I was standing next to my running SAME which has the same glass filter bowl (and the same lift pump), my glass bowl didn't have any air bubbles/cavitation like your one does, it just had one big "bubble" at the top which arrives when the engine is running and stays there until it's turned off.

I started it yesterday to show the neighbor what it's doing, without the metal filter in the glass bowl... with the filter removed, nearly all the cavitation and air gap at the top of the bowl goes away. Just an occasional tiny bubble in the incoming fuel, that seems normal for any fuel system. Perhaps just a bad design, with the way the fuel hits the top of the metal filter sloshing it around and causing the bubbles.