Oil & Fuel DK35 engine oil level increasing

AndrewInOz · Nov 13, 2011

Any suggestions on what I've overlooked ...
Kioti DK35 with 12 speed gearbox & mid PTO option. 200 hours.
Engine oil level increases about 1 inch after an hour operation ... oil is clear & not overly thinning so maybe transmission oil leaking in there. Hard to gauge but looks like transmission oil level is dropping too. Not certain though.

I've stripped down the Casappa tandem hydraulic pump : hi pressure seals good, installed new shaft seal but same problem.
Then fitted a complete new hydraulic pump with a revised part number : no better.

Replaced injection and lift pumps to cover possibility of engine oil level increase actually being fuel but still no better. Engine always ran well and smoothly in any case.

I've looked over the engine and cannot see any other places oil or fuel could leak into the crankcase. I can't see an oil cooler anywhere.
The clutch is fine so I don't suspect internal leakage somehow from clutch housing.

This tractor located away from my home & only occasionally used for mowing (which means replacing the engine oil each time at the moment).

I wonder if anyone out there can think of anything ( anything ! ) else to check.
TIA.

tpulley · Nov 13, 2011

Just a thought Andrew, I think I would try an oil analysis to determine what is in your oil. Here is a place I googled and found.

Blackstone Labs

LaVoie Equipment · Nov 13, 2011

You should definitely find someone to check your oil. I recommend running you tractor for a short period, then pull an oil sample and do not run until you get results. Caterpillar construction equipment dealer can do fastest without having to send away. Your JD dealer may also. Someone locally always has capability.

Couple of notes. If it was fuel you could smell it and is very harmful to engine. Hydraulic oil is being deposited in engine via hydraulic pump - it is aluminum, expanding and contracting with heat, could be cracked where you cannot see. And of course water will turn engine oil white.

Sounds to me you have a hydraulic pump problem.

PoorMansCat · Nov 13, 2011

x3!!!! Get an oil sample pulled and find out exactly what youre dealing with,..

Coyote machine · Nov 13, 2011

AndrewInOz said:
Any suggestions on what I've overlooked ...
Kioti DK35 with 12 speed gearbox & mid PTO option. 200 hours.
Engine oil level increases about 1 inch after an hour operation ... oil is clear & not overly thinning so maybe transmission oil leaking in there. Hard to gauge but looks like transmission oil level is dropping too. Not certain though.

I've stripped down the Casappa tandem hydraulic pump : hi pressure seals good, installed new shaft seal but same problem.
Then fitted a complete new hydraulic pump with a revised part number : no better.

Replaced injection and lift pumps to cover possibility of engine oil level increase actually being fuel but still no better. Engine always ran well and smoothly in any case.

I've looked over the engine and cannot see any other places oil or fuel could leak into the crankcase. I can't see an oil cooler anywhere.
The clutch is fine so I don't suspect internal leakage somehow from clutch housing.

This tractor located away from my home & only occasionally used for mowing (which means replacing the engine oil each time at the moment).

I wonder if anyone out there can think of anything ( anything ! ) else to check.
TIA.

Is the tractor under warranty?
YES, definitely do an engine oil analysis.
And as already stated DO NOT use the tractor until you have a diagnosis and have corrected the problem- otherwise you could do catastrophic damage to engine and trans.

somguyss · Nov 14, 2011

I will go ahead and tell you the problem, the problem is that your seal on your hydraulic pump has blown out an it is sucking the hydraulic oil from your transmission into the engine. I recommend that you either replace the pump if out of warranty or get it to the dealer for warranty, run the tractor as little as possible to get on trailer or to work area. If you run it for long period of time you will destroy your engine I PROMISE. I have seen this several times, you can either take my word for it or continue. I'm by no means trying to make yea made, but I know these tractors very well and that is what s wrong! Replace pump, no parts to repair and change engine oil and filters and top of transmission fluid and life will be good. I promise if you continue to run you will be replacing an engine and KIOTI will not cover it if you keep running.
I have worked on your ORANGE machine, also the White ones and also on the RED ones as well, I know the machines better than I know my wife!

MotorSeven · Nov 14, 2011

From what Andrew posted, he has already replaced the pumps(IP and Hydro) and still has the same problem.

somguyss · Nov 14, 2011

As far as repairing the Caspa pump the repair parts didn't come from KIOTI they have no internal parts for the pump other than the outer o-rings. As for the new pump installed and still does it just means that he could have gotten another pump thats doing the same thing. New part out of box defective isn't uncommon at all. He stated the clutch is fine so I can't imagine that the transmission input shaft seal and the rear main seal both failed at the same time and the hydraulic fluid is making it's way threw the transmission filling up the clutch housing and then being sucked in to the engine. So that being said the only other place where hydraulic fluid can contaminate the oil is by the hydraulic pump, no hydraulic lines for the tractor run threw the engine and if there was an oil cooler for the hydraulics it would never come in cotact withthe engine crankcase.
I trust new parts as far as I can throw them, if it is made by hand there is room for error, I would just look at the pump again and verify.

AndrewInOz · Nov 14, 2011

Thanks everybody for yr comments. How helpfull this site is...
Well out of warranty ( of course ).
The Cassappa hydraulic pump was in very good condition, but I just replaced the shaft seal on reassy. BTW, even though pump is a special, Casappa themselves do sell a seal kit for this common family of pumps.
But I subsequently replaced the entire pump with a new one from Kioti. The part number has been revised probably to reflect the new Asian manufacturer.
Fit up was perfect & I'm confident this is not the source of the leak.

Yes, I avoid running the engine .. for these tests I have changed the engine oil each time it gets up about an inch which is only an hour or so. Viscosity looks fine. We'll need to work tractor soon so I must sort it out before then.

With hindsight, an oil test should have been the first move, but I was sure back then this was hydraulic oil and an oil test might not show up low dilutions of a similar oils. I'll get a sample tested asap to eliminate fuel possibility.
But in any case, the makeup can only be transmission oil or fuel & only places I can see these fluids near the engine are the 3 pumps already replaced with new ones from Kioti.
I'm sure I'm missing something simple here ..
Anyway, next visit I'll try to measure the dilution rate, and get a sample off for test.
I notice in the service manual diagram, the drive shaft to front axle seems to go thru the clutch housing and a cast void in the engine sump. I wonder if that void is / should be dry?
Although leakage from here would likely always occurr, and not just while engine is running as is the case.
I'll keep u posted and appreciate the help.

AndrewInOz · Dec 26, 2011

Next installment:
( DK35 with rising engine oil level : new fuel lift & injection pumps, new hydraulic pump)

Had an afternoon on site over the break on this one :
- fresh engine oil and ran engine unloaded. oil level gained 10mm (3/8") on dipstick in 10mins running.
- bypassed the fuel lift pump : oil level gained another 10mm in 10 mins running.
- removed the hydraulic pump and ran engine : another 10mm gain.

So we have stationary engine running at hi idle and only liquid connection is fuel to injection pump ( and water which is never consumed ) and still with rising oil level.
Drained the oil back to start level and we gained very roughly 1.5 liters (0.4 gallon) in 40 mins running at 1600 rpm. No more testing on this oil.

Although this engine starts and runs perfectly, with no smoke, the injectors are all I can think of. ( anything else?) Chance of orig + new inject pump both faulty is slim.

Now have dilution rate and an oil sample for testing. However its holidays so I'll have injectors out asap before labs reopen. Will post result. I can quick check viscosity and ignition on oil but really must be fuel in there.

Note for others diagnosing these areas:
- the engine ran fine on level ground with lift pump bypassed : gravity only via filter from half full fuel tank. I started out with an electric pump in there, but was messy and not necessary for engine to run.
- the hydraulic pump can be removed leaving the drive gear housing in situ. When running level, there is just a managable slow dripping from the open housing.

Coyote machine · Dec 26, 2011

If all that is connected as far as fluids is fuel and radiator water, and the water level is constant, then fuel is all that's left. What if anything have you done with injectors so far- (sorry no time to traipse back through the thread).
Have you pulled them for at least a visual inspection?
Post back please.

AndrewInOz · Dec 26, 2011

I'm busting get over there today and pull the injectors.
I don't have a tester, but hopefully there will be a visual clue as u suggest.
Unfortunately there won't be any workshops open here till next week so I'm on my own. There is a hand cranked single cyl engine here I maybe able to safely test injectors on. Pretty cautious about that tho.

Coyote machine · Dec 26, 2011

You need a spray pattern tester to test for spray pattern and leakdown parameters. Any good diesel shop will have the capability to test them- which is what I'd do if I were u.
I'd be real careful using a single cyl engine to test your injectors.
Injectors should spray an even conical pattern and not spray like a dog peeing on a flat rock. If you see any questionable visual signs inspecting the injectors then replace them.
Why didn't you start by checking these prior to replacing the inj pump?!

PoorMansCat · Dec 27, 2011

couple questions... what type of injection pump/injectors does this engine have? Is it a rotary pump?
Do the injectors have overflow return tubes and are they under the valve cover? While one can never be 100% positive, I would think that if the injector was pissing, it would be fuel knocking and/or have some abnormal smoke??

seacap04 · Dec 27, 2011

I have been following this thread, but everything I thought of was covered. However PoorMansCat might have nailed it. The GM diesels I have operated in the past you always checked for rising oil levels due to high presure fuel lines under valve covers.

DK35vince · Dec 27, 2011

I have an older model DK 35. There are no fuel lines under the valve cover on mine.

DK35vince · Dec 27, 2011

seacap04 said:
The GM diesels I have operated in the past you always checked for rising oil levels due to high presure fuel lines under valve covers.

I've seen that happen several times on the old 2 stroke Detroit diesels. Leaky fuel lines under the valve cover.
But I don't believe that is the problem here.
I know there are no fuel lines under the valve cover on my DK 35.

seacap04 · Dec 27, 2011

Yea, most new diesels don't. Thought about that after I posted.

Injectors- Only way to get that much dulition would be to have tips missing. But no fuel knock or smoke

Injector pump-front shaft seal was leaking into timing gear cover. He had pump rebuilt. I would still check end play on shaft. I keep coming back to this in my thoughts.

Head gasket- No coolant loss or gain and no overheating issues.

Thermal expansion- Checking oil too soon after shut down would indicate low level. Not running engine long enough to be an issue.

I post this as this is how I solve problems professionally. I state the facts as I understand them and want someone to find my errors in rejection of cause or totally missed thoughts.

seacap04 · Dec 27, 2011

He also bypasted lift pump so not the issue

AndrewInOz · Dec 28, 2011

Thanks so much for all for yr inputs. In no order...
- barely perceptable bypass flow out of the injectors in tubing which is external to engine anyway.

- I couldn't believe dipstick gain in first 10 min test, so i did another 10 min with the exact same result. All hot by then. Rested about 2 mins before taking dip level. Dips found to be consistant any time after 2 mins stopped. It all appears to be very linear ie run x mins & get gain y. I'm kicking myself for not thinking to do a test at low idle too.

- injector pump is Korean branded "Bosch K type". This is a cartridge of 3 plungers and cam followers. Not a rotary. The cam is part of the engine. If fuel leaked past any of the plungers its' in the crankcase. I applied lift fuel pressure to the original pump inlet on the bench. No leakage either static or operating plungers by hand ( not real valid test as no injector backpressure ). BUT brand new injection pump from Kioti fitted anyway with exact same symptom.

- it is easier for me to throw new parts at it whenever I get to this machine.
In any case, I didn't mind changing inject pump based on stories about jammed racks. The pump is easy to change ... bit easier than pulling injectors. I dissassembled one plunger from the old pump: looked fine.

- pulled injectors yesterday and looked ok to my untrained eye.
Quick test was : By rotating the 3x fuel pipe assy 180deg, the injectors could be located safely pointing outwards at the front of the engine. Starter spins engine pretty fast without compression. All appeared to give a good mist but was not a test rig to get too close to. All commercial shops closed here till probably next week so will have to wait for definative answer on leakage or possible hi cracking pressure (that might cause both IP pumps to bypass??).

- walking around the engine I can't see any other path for liquids. Plug in bottom clutch housing is dry. ( Why a plug there ?) The oil level quickly stabilises after shutdown and remains there until next run. Level only ever increases. We have three 35 hp FWA tractors and this one has best low end torque / quietest / no smoke ( but others 1-2k hours & diff makes ). Motor is fine otherwise.

Thanks again yr interest. If these injectors are ok, I'll be climbing up the wall!