Gehl Deutz BF3 1101 Fuel or Valve Issue? Help!

[Grandpa Chuckie]

I have a situation that stumps me. Gehl DXT4835 with Deutz BF31011F engine with 900 hrs. Original owner. Few months ago added diesel fuel from a steel fuel can. I noticed some rust in the bottom of can but figured the Gehl fuel filter would catch whatever particles entered fuel line. Within a day, I noticed a slight miss and a vibration at idle.Then it got worse and worse. Then a couple times after shutdown, it wouldn't start. Cranking fine, but no ignition. I waited about 15 minutes, then it fired right up like normal.

So, I figured fuel issue. Replaced Gehl with another, a Baldwin. Started up and same missing, and got worse the longer I operated, so much so I thought it would stall, so limped back to garage. Here's what I did: 1. Removed lift pump and cleaned tiny filter (a bit of crud but not enough to block) and inspected diaphragm- AOK. 2. Drained fuel tank. Refilled with fresh diesel. Flushed fuel lines. Cranked and took a while but fired, sputtered, and then purred....for about five minutes at idle then that same rough idle started. Throttled to mid range and same random missing started. So I operated a bit and started sputtering so much again, thought it would stall. Back to garage. Turned off, then tried to restart and it would not. Let sit 15-20 minutes, fired right up, but still same rough idle. And same faltering at mid and high RPMs. Fired its fuel (crud or water)

1. Drained tank. Diesel was pretty clean but about 1/4 teaspoon of water and couple pieces of rust?. Flushed tank till clean. Refilled. 2. Changed filter. 3. Removed electric fuel shut off and tested on/off again and again and shook and wiggled solenoid and no fault. 4. Pulled timing belt cover and belt looked fine but read the belt needs to be changed at 2500 hrs or 5 years (mine is 20 yrs old). So replaced belt and tensioner using timing pins and tensioning gauge (all was major as so much had to be removed-oil radiator & hydraulic radiator/shrowd, air filter, turbo intake, etc). 5. Removed and inspected 3 injectors. #2 was slightly carbonized, #1 carbonized more, and #3 was so bad it had "chunks" and plugged ports.

So, I cleaned using carb cleaner and toothbrush. Then put all three in ultrasonic cleaner and that worked as all ports (5) on each injector showed good spray. Reinstalled everything. Fired up and worked great at all RPMs and I figured problem solved. So started using and pushing dirt. That lasted about 1 hr. Same symptoms reappeared. And I shut it down outside my garage, and it would not restart. Waited 30 minutes and fired up but rough idle, again. Same struggling at midrange and high RMPs, again.

Pulled injectors, and same cylinders showed carbon as mentioned above, just not as bad. So, just me thinking, maybe its valve lash as the carbon is a little on one and most on #3, so I did a check on valves as intake needs to be 0.3mm and exhaust 0.5mm. All a little big, so I adjusted so feeler gauge had slight resistance with engine cold on valves. But back together. Ran and was good, for about 30 minutes. Same thing, again. Each same.

I pulled and cleaned injectors, again. Did a repeat. Results, exactly the same. So I pulled injectors. Same appearance. #3 was not as bad as first time pulled.(see photo-comparing all 3.....anti-seize is the silver) Reminding this engine has never had any work done to it, just fluid changes, and I hardly ever run it at full throttle. Usually idle or just high idle even when pushing dirt.

Now I'm thinking maybe I damaged #3 somehow when cleaning, so I ordered new ones. In meantime while waiting for new ones, I made a tool to turn engine over to find TDC on #1 and check valves as per manual. Very close, maybe 0.05 variation on #1 & #3. So I adjusted. New injectors came and installed. Started engine and it sounded really good at idle, mid and high RPM. After about 10 minutes I drove around, swapped to forks, then it started missing again. I unloaded the delivery truck and just made it back to the shop as the engine was faltering so bad as originally. NO!!! So I pulled the injectors (getting faster at this) and #1 some carbon, #2 clean, #3 bad.

I am at a lost as what to do! This machine has been so reliable and consistent! Please offer suggests, comments! Thank you!!

 

[foton]

I would think the black carbon is from either lack of compression or overfueling, and since it happened all at once ,that takes out I would think compression. And since you know that there was trash intruduced into the fuel system and you replaced the injectors,kinda leaves the pump. I would make sure though that your fuel tank has proper venting ,you do not want a vacuum on it, I am kinda wondering that really you have a lean condition due to a blockage some where (including the air vent typically in the fuel cap), the resting time in between starts and it running and starting right up,makes me think that. You could use a clean remote portable fuel tank(like a boat uses) plumbed to the lift pump to isolate if necessary.

 

[Grandpa Chuckie]

I spoke with "Chris" at Foley Engines, and he thinks maybe check valve clearances again, and gave me some tips on that process. But he doesn't think that Is the problem. Since the first set of injectors showed cylinder #3 is the worst, and #1 the best, and replacing with new injectors with same results leads him to think it's a blown head gasket, or compression problem. He also suggested make sure the air cleaner is good and all connections tight. (easy check)

Foton, I don't think it is an air vacuum problem, but your solution is relatively easy and worth a try and I will rig up an elevated fuel supply. Thank you for the suggestion!

I going to research compression testing and how to do it, as per Chris suggestion.

 

[Grandpa Chuckie]

Couple more observations:
1. There is no exhaust smoke while running, even when the engine if faltering. Only black smoke when I throttle it, and then just momentary.
2. This one bothers me. I have noticed my engine oil level coming up just a little, and it has a slight odor of diesel. I replaced the lift pump as that diagrahm if torn can allow diesel into the fuel. The diagram was not torn nor any holes.

 

[Jeffro]

I have a 4 cylinder Deutz motor in my bobcat s250. I have a fuel pump on each cylinder. It maybe a case that you have one of those going bad.
Also mine ran bad after I first used it brush cutting with it. Ran great for 30-45 minutes of cutting then when more of a load was put on it. It would start missing and barely turn cutter. Puff black smoke out. Let sit and would run great again but after 10-15 minutes do same thing. Previous owner had an exhaust leak which melted cover of air box and it was letting dirt into filter and plugging it up. I replaced the whole air box and didn't have a problem after that.

 

[foton]

I agree a compression test will tell you a lot at this point. And it will give you a reference point on engines condition overall.

 

[Grandpa Chuckie]

Thanks for comments! Much appreciated. Before I do a compression test, I want to make sure I have the valve adjustments correct. I was a bit confused on finding TDC on cylinder 1. Manual states "exhaust valve about to close, inlet valve about to open". I was confused be of conflict between various sources, but I think I have it right now. Is this correct: both valves need to be open the same amount--both slightly open?!?!

 

[foton]

I have not done a deutz, but what I have found to be the best way to to bar or use the crank bolt to turn the engine over till one valve is down,then set the other one on that cylinder ,then turn it some more till the valve that you just did goes down the set the other one,continue till you get them all done. there is plenty on you tube to watch on this. I assume that the exaust and intake valves have different gaps ,so make sure you get each valve identified before setting.

 

[Grandpa Chuckie]

It finally warmed up outside enough for me to do 2 things; adjust the valves and check the fuel."Kris" at Foley engine got back with me to confirm valve adjustment. His points were very clear to set the engine TDC, watch #1 cylinder (the one closest to the flywheel-opposite of the the crankshaft pulley), both valves must be slightly open. Exhaust will be closing and intake opening. To be exact, hand turn crankshaft pulley clockwise until I cannot turn the intake pushrod. Mark crankshaft pulley and block. Continue turning crank till exhaust valve pushrod cannot be rotated. Mark that spot on crankshaft pulley and block. The spot between the two marks is TDC. I then adjusted the intake valves to 0.3mm and exhaust to 0.5mm so that there is slight resistance. I then asked what is "slight"? He replied that if you had a large phonebook and put a loose sheet of paper in the open phonebook, and then closed the book and remove the loose page from the phonebook, that is "slight resistance".

So I went through the valves as shown in the Deutz manual. My valves were a bit off. Made the adjustment and fired it up. Sounded good, then at about 5 minutes the same faltering started. I carefully watched the exhaust and recorded it. There was no smoke at all. No white smoke and no black smoke. I will try to post that video.

The next thing I did was took "Foton's" advise to mount a separate fuel tank and fuel line. So I used an old plastic ice cream container (square not round) and attached a nipple and fuel line. By-passed the lift pump and filter and went straight to the first injector pump, and hose clamped both ends of fuel line. The tank I set atop the cab and poured a quart of #1 kerosene fuel oil, knowing that is clean as I am starting to question the quality of the local diesel supplier. Oh, I let the air in the fuel line slowly bubble up through the qt of kerosene. Took about 10 minutes. Rattled the line and few more bubbles came up. Then cranked on the starter. Took a couple times, and the engine fired and faltered a bit, some black smoke, and slowly smoothed out. Checked the time. Five minutes and running well. Check fuel reservoir and good. Ten minutes--good. Fifteen minutes cycled throttle all the way idle to full throttle. All good. Continue moving throttle for additional five minutes. No smoke, no faltering, and no missing.

So, my next step is to drain the fuel tank again (this will be the third time) and drive to our local farmers diesel and get some of that dyed diesel. I figure if the farmers get there fuel there, it has to be good. I will also change my fuel filter again (this will be the fourth fuel filter- Baldwin)

I appreciate all the suggestions. Just like the old saying, "two heads are better than one"!

3 short videos: 1st = cold idle, 2nd= 2 minutes idled, 3rd = 3 minutes after startup

 

[foton]

that is great that you have your problem on the run now. but let me say kerosene has not much in the line of lube qualities to it ,run it as little as possible or add some non dertergent oil to it ,maybe 50 to 1. I am guessing. I am wondering if maybe the fuel pick up is getting plugged with something, maybe if the junk can not be found, that the I assume the filter on the end of the pick up can be modiffied and made bigger so not as easily restricted. And maybe to save a few bucks get a glass jar and pour the contents of the fuel filter into it. If there is no trash I guess the trash is not making it that far and I would reuse it. and I use red fuel from the co-op with no issues. As another thought when or if you do pour the filter out into a glass jar let it sit for 5 min. and look for water, it will seperate from diesel and be easy to see,should not be any.

 

[haymaker]

Approx. 1 oz. of outboard motor oil per gallon of kerosene works too in a pinch.
My cousin gets Jet A for free when he flushes tanks at the airport. He uses 2 cycle oil and mixes the free stuff with diesel in all his equipment.

 

[ward]

I had a machine that someone had gotten trash in the fuel tank, the tank could not be removed however I could get a hose in and siphon fuel out and move the hose in the bottom of the tank and got 95% or better of the trash and water to siphon out the filter took care of the rest it took me better then an hour to get it done and I had to keep running the fuel through a coffee filter and putting it back in the tank .

 

[haymaker]

It finally warmed up outside enough for me to do 2 things; adjust the valves and check the fuel."Kris" at Foley engine got back with me to confirm valve adjustment. His points were very clear to set the engine TDC, watch #1 cylinder (the one closest to the flywheel-opposite of the the crankshaft pulley), both valves must be slightly open. Exhaust will be closing and intake opening. To be exact, hand turn crankshaft pulley clockwise until I cannot turn the intake pushrod. Mark crankshaft pulley and block. Continue turning crank till exhaust valve pushrod cannot be rotated. Mark that spot on crankshaft pulley and block. The spot between the two marks is TDC. I then adjusted the intake valves to 0.3mm and exhaust to 0.5mm so that there is slight resistance. I then asked what is "slight"? He replied that if you had a large phonebook and put a loose sheet of paper in the open phonebook, and then closed the book and remove the loose page from the phonebook, that is "slight resistance".

So I went through the valves as shown in the Deutz manual. My valves were a bit off. Made the adjustment and fired it up. Sounded good, then at about 5 minutes the same faltering started. I carefully watched the exhaust and recorded it. There was no smoke at all. No white smoke and no black smoke. I will try to post that video.

The next thing I did was took "Foton's" advise to mount a separate fuel tank and fuel line. So I used an old plastic ice cream container (square not round) and attached a nipple and fuel line. By-passed the lift pump and filter and went straight to the first injector pump, and hose clamped both ends of fuel line. The tank I set atop the cab and poured a quart of #1 kerosene fuel oil, knowing that is clean as I am starting to question the quality of the local diesel supplier. Oh, I let the air in the fuel line slowly bubble up through the qt of kerosene. Took about 10 minutes. Rattled the line and few more bubbles came up. Then cranked on the starter. Took a couple times, and the engine fired and faltered a bit, some black smoke, and slowly smoothed out. Checked the time. Five minutes and running well. Check fuel reservoir and good. Ten minutes--good. Fifteen minutes cycled throttle all the way idle to full throttle. All good. Continue moving throttle for additional five minutes. No smoke, no faltering, and no missing.

So, my next step is to drain the fuel tank again (this will be the third time) and drive to our local farmers diesel and get some of that dyed diesel. I figure if the farmers get there fuel there, it has to be good. I will also change my fuel filter again (this will be the fourth fuel filter- Baldwin)

I appreciate all the suggestions. Just like the old saying, "two heads are better than one"!

3 short videos: 1st = cold idle, 2nd= 2 minutes idled, 3rd = 3 minutes after startup

I can't wait to hear what the result and resolution of this one is!!

 

[Grandpa Chuckie]

Update: problem solved!! Yahoo! Thanks to above comments. Even though I drained the fuel 2 times, I noticed the drain plug is about 3/4" above the bottom. So I placed a drain pan underneath, and a wide mouth funnel on inlet and "splashed" 1/2 gallon diesel to stir up the bottom. And sure enough, a lot of crud came out. I then modified an old plastic pump sprayer and attached a 5/16" vinyl tubing with a 4+ft stiff metal rod to keep tubing straight, and pushed it through the inlet to the bottom of the tank. With filtered diesel fuel in the sprayed and pumped up, I started spraying. I kept spraying and collecting fuel out the bottom, till it came clean. WOW! Rust, nasty looking sludge, water, and really fine, gritty black stuff that would smudge my fingers like soot. Not idea what or where this came from.

Retrospect, I can't believe I didn't see the problem. The space below the drain plug acted as a reservoir for debris. And once the machine was operating, the fuel would slosh around and stir the sediment, then sucked up by the lift pump.

I also discovered my portable metal fuel tanks had crud in the bottom of each. So I just purchased some yellow plastic diesel containers as I can see inside those. The bottom of metal cans is hard to see debris. I also purchased "off-road" dyed diesel and upon inspection in the new containers, looked clean!

I took the suggestions of adding a diesel lubricant (I used Power Service antigel/lube agent) to the new fuels (current temp=18 degrees). With the fuel lines reattached, the machine cranked right up, sputtered a bit (air), and then purred along for 20 minutes. Now that I got the air out and it's running, I will replace the fuel filter, again, once this arctic blast leaves our area next week.

Again, thank you for your suggestions! I will post an update once I change the fuel filter and get back to moving dirt!!!!

 

[ward]

the black stuff that looks like soot may be accumulated dead alge, I would also hit it with

Clear-Diesel Fuel & Tank Cleaner

https://powerservice.com/products/

 

[foton]

the way these new portable fuel cans suck, if those metal ones are in other wise good shape ,try the product Red Kote, just follow the instructions well, I have saved several no longer availabe fuel tanks with that stuff. glad we were able to help you out, it is kinda tuff over the computer vs. being there hands on. and that black sludge can be the excretement of diesel bugs. they must have water to survive in diesel which they eat I guess ,yuck I do not like it. anyway if you have a bulk fuel storage tank drain some off the bottom and look at it. if there is wierd stuff in it , it needs a biotoxin treatment to kill them. and the power service brand works well. these bugs might be the reason your metal tanks bottoms were if ruff shape.