Deutz 4 cyl. diesel start, stall, run slow, stop, repeat

   / Deutz 4 cyl. diesel start, stall, run slow, stop, repeat #1  

PowerTracManiac

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Location
Central, Virginia
Tractor
Power Trac 1460
Wait a little bit and it will start right up again and run for a short time then run very slow then die out?
I'm thinking fuel flow blockage.

The fuel exit line is up high on my tank. Must be a tube that goes down to the bottom of tank and the fuel pump or injectors I guess must create suction to get fuel up to the engine?
I don't see a fuel filter and I don't have fuel pressure guage on the machine.

My plan is to disconnect the main fuel line at the fuel motor line (there is a hose clamp there) place a rag over the gas intake cap and blow compressed air into the tank and see if the fuel comes up and out of main tank line?
Any thoughts on that?
Also, if I pinch off the line to the injectors on the fuel line portion that goes to the engine before I disconnect the main line from tank will that be OK or will I have some sort of a priming issue with the Duetz?
20200605_150712.jpg
 
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   / Deutz 4 cyl. diesel start, stall, run slow, stop, repeat #2  
When mine did the same thing it was water in the diesel. Changed the filter, added a separator in line good to go.

I think you're right about the clamp and prime. But someone else will know better than me.
 
   / Deutz 4 cyl. diesel start, stall, run slow, stop, repeat #3  
I believe that the diesel line in the photograph is the diesel return line. The main outlet is usually in the center of the bottom floor of the tank.

The symptoms sound like fuel starvation. The number one cause is bad fuel, though it would not hurt to check for water in the fuel. You can shine a bright light into the fuel tank to see if the bottom is clean. You can also see how clean the screen in the tank is. My 3 cylinder Deutz has a clear fuel prefilter in the fuel line, a prefilter on the engine just before the fuel pump, and a screw on filter on the pump itself. As a heads up, some of the other owners have found quite a bit of crud on the engine pump prefilter, so be sure you take it out and check it.

I do not know if it helps, but here is a quick overview of the fuel system. The fuel flows by gravity and vacuum through the prefilters and filter to the fuel pump that boosts the diesel to an intermediate pressure before going to the injectors, where the diesel is split, with the bulk of it being used hydraulically to boost a little bit of diesel to injection pressure into the cylinder. The bulk of the diesel is returned to the tank. This means that Deutz engines rarely need priming, and has the added effect of extensively filtering the diesel through multiple passes through the fuel filter.

Good luck! I hope that it just is a bad batch of fuel that clogged your filter.

All the best,

Peter
 
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   / Deutz 4 cyl. diesel start, stall, run slow, stop, repeat
  • Thread Starter
#4  
Very helpful!
Seems that I am on the right track with a fuel related issue. I was wondering about that fuel line in my photo and it seemed odd to me the way it was run. Haha! Makes more sense that it is a return line as you said.
Will check the bottom of my fuel tank for more lines and with a flashlight this weekend.
 
   / Deutz 4 cyl. diesel start, stall, run slow, stop, repeat #5  
You said you didn't see a fuel filter. You do have one and with the tolerances on a diesel injection pump they are vital. You should start by locating and then changing the fuel filter. When you have it off, pour it into a clear container and if it has water, there will be noticeable bubbles on the bottom. If a lot of water, drain the tank enough to get it out or it will grow algae. A good diesel fuel supplement that deals with water would be a good idea for you (if you find water in filter).
 
   / Deutz 4 cyl. diesel start, stall, run slow, stop, repeat #6  
On my deutz and probably yours the fuel comes out of the bottom of the tank and is gravity fed over to the pump. On the front of the pump is a philips screw. Undo this and pry it forward. There is a circular filter. Clean and replace. It is the filter that used to plug up on me. Then the fuel goes to the fuel filter and then up yo the injectors. The injectors are mechanical, meaning the cam in the engine pushes on them and causes them to spray fuel into the engine at high pressure. The unused fuel then flows back to the tank. I have fought minor fuel issues like water in the tank and sediment in the tank. I ended up cutting a hatch for my tank and coating it in POR paint. I also bought a water removing filter for my fuel pump. In addition i made a 50 gallon fuel carrier that i can pickle fork into the truck to get off road diesel.
 
   / Deutz 4 cyl. diesel start, stall, run slow, stop, repeat
  • Thread Starter
#7  
You are correct and my fuel supply does gravity feed from the bottom of the fuel tank. The other fuel lines in the previous photo are return lines as stated.
My supply fuel line comes from bottom of tank to a gold canister mounted on a silver block. There are 2 wires coming off the silver block and it says flow on it with an arrow.
Fuel line then goes to the fuel pump and the fuel filter before going to engine.

The machine started running rough/slower and I parked it after running it for about 45 minutes.
I let it cool down and then I added fuel.
The fuel that I added to the machine had been sitting for about 4 month outside in a plastic 5 gallon deisel container.
I don't have a fuel/water seperator and I will purchase to add to my fuel fill process.

Anybody know what that gold canister/silver block is?
20200608_095601.jpg
If I disconnect the fuel lines or remove the fuel pump cover to clean out the fuel pump canister do I have to do some sort of priming process before I try to start it again?
20200608_084421.jpg
 
   / Deutz 4 cyl. diesel start, stall, run slow, stop, repeat #8  
Duetz 4 cyl. deisel start, stall, run slow, stop, repeat

I am not sure but the first photo looks like a electric in off valve. Mine does not have this. The second picture is you PRE filter and lift pump. Undo the Philips to find the filter screen. And it is the single philips on the round cap.
 
   / Deutz 4 cyl. diesel start, stall, run slow, stop, repeat #9  
Oh. No priming. Just takes a moment when turning over. I installed a manual on off valve on my fuel line to keep the fuel in the tank when changing filters.
 
   / Deutz 4 cyl. diesel start, stall, run slow, stop, repeat #10  
In your picture (top) the gold object looks to me to be a fuel filter (that may be restricted), the silver item looks like a inexpensive electric pulse fuel pump. You shouldn't need these as the other picture shows the factory mechanical lift pump (very high quality). I would get rid of that electic pump and fix the factory pump (if it is broken). Like woodlandfarms said, there should be a screen to keep particles out of the factory pump. The previous owner might not have known this and installed the electric pump to try to push through the clog. Now it may be so bad, it will have to be cleaned.
ALSO it looks like at least one of your fuel line hoses is weather cracked. The lines on the Deutz tend to move around quite a bit. You should change bad lines before it breaks and you get a fuel leak on a hot engine.
 
 
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