The Art of Delivery, fuel'd with questions...?

[TBDonnelly]

Ah yes a riddle. Now the scenario, then the questions.

For the past year - or better - my 2004 CK30 has had an intermittent, loss of power/erratic RPM issue.

Allow me to explain. This tractor is mostly used for short bursts of time & seldom used in extended time situations(more than 30 minutes continuously). The loss of power/erratic RPM's issue would only surface during continuous use, for greater than 30 minute time periods. Due to the 'characteristics of use' the 'symptoms' would usually 'show' once during a 6 month time period. The unfortunate part is, during an extended snow event was one of the times when the 'symptoms' came to the surface. The tractor has never been used for mowing grass, is kept in either a carport or garage & never stored outside in the elements. The engine has never totally died, if the engine did quit, it would restart....it would continue to run erratically, I never was stranded with a totally dead tractor.

What is the cause of the 'symptoms' and the 'fix'?

The discussion period is officially open!

Don

PS: I've only discussed this with one (1) TBN participant and he is disqualified from comment! (at least initially )

 

[ToadHill]

I'd look at the fuel filter.

 

[TBDonnelly]

I'd look at the fuel filter.

I changed the fuel filter each time the symptoms surfaced. The used fuel filter is pictured below. The engine would run OK with a new fuel filter until an extended use(greater than 30 minutes).

The owners manual states a fuel filter can be cleaned with kerosene. After this happened a couple of times I started soaking the used filters in kerosene and blowing them out with an air gun.

Don

 

[TBDonnelly]

All engines need compression,air, fuel , & ignition in balance to work properly, slight inbalance = poor performance, gross inbalance = dead engine.

Compression: worn rings tend to seal less when warm, engine may start & run then degrade as parts expand & oil thins; worn/misadjusted valves may be hard to start but seem to run ok once started

Engine only has 360 hours, I hope I'm OK in this area.

With fuel: bad quality due to aging or contamination/seperation, plugged vent in fuel tank, plugged filter, degraded fuel lines. Misadjusted
choke becomes a problem after warmup. Fuel shutdown solenoids may be partially blocked. Jets get dirty, carb vents get plugged, ie mud wasps fill vents with nests.

Fuel has been a question in my mind. Could it be? I don't store extra fuel since I don't use that much. 5 gallons can last me several months during periods of light use. I've always used Power Service additive year around and have increased the portion with the new Low Sulfur formulations. Fuel always looked clean and green in the fuel bowl. Could not detect any foreign substances or crud on the fuel filters.

Air ; plugged filter, but probably would present immediately

New air filter installed during this process. Did not fix the problem.

Ignition: tends to either fail warm -starts then degrades/quits, or fail cold -won't start unless heated but once started runs ok. OR it just starts hard & runs crappy all the time. Timing can affect highspeed performance. Fouled/cracked sparkplugs (Diesel engine not gas)effect running (should be light/chocolate brown electrodes when running well).

Overheating will cause poor performance which is running time relevent.

Have not had any overheating issues.

Governor problems can be time/heat related.

Even a mouse nest in the muffler has slowed many engines to an idle then quit.

No mice detected. Knock on wood.

Basically pick one senario at a time & confirm/eliminate it's affect.

Since this is a riddle,winter related, & you have presumably found the answer, I'd also look for ice in an odd place. I've seen ice on the vacuum side of fuel pumps that would allow an engine to start, die at speed, then run again after sitting, especially after sitting in a warm space. Seen this on snowmobiles & 4 wheelers. Have also experienced ice under the oil in an oil bath air filter that blocked airflow. MikeD74T

The issue has occured both in warm weather and cold weather, I can't say it's cold weather specific.

Mike, thank you. You have covered a lot of ground and given a lot to consider.

Don

 

[polo1665]

Fuel pick-up blocked in fuel tank.

Mark

 

[MikeD74T]

Don, Glad you found info helpful. I pulled my post before you replied as mine is mostly gas engine related & realized you have a diesel problem.
Agree with Polo, possibly a foil/plastic seal from an additive bottle's floating around the tank bottom & getting sucked onto the outlet? MikeD74T

 

[TBDonnelly]

Fuel pick-up blocked in fuel tank.

Mark

I fished around in the bottom of the fuel tank with a long reach 'claw', could not come up with anything. This is a difficult area to check because of the irregular shape of the fuel tank. After the most recent occurence I did drain the fuel tank and had a good fuel flow from the hose exiting the bottom of the tank.

After draining the fuel tank, I filled the fuel bowl with fresh fuel, replaced the fuel filter with a brand new, not recycled fuel filter and poured some fresh diesel fuel into the tank. The engine started fine and I let the tractor sit with the engine idling for 30 minutes and the engine ran OK. Then I went out to the compost pile to flip some leaves and the problem surfaced again. Using the loader would bog the engine down and the erractic RPM's would continue. Could not move the tractor without the engine bogging down. Even at a stand still the RPM's would flucuate.

Don

 

[Gittyup]

First thing that comes to mind is that it might be thermally related. Could an electrical part be changing after warm up (like a solinoid), or some sort of expansion caused by heat, maybe causing air to be drawn into the fuel line? Perhaps fuel pump or relay? Or even hydraulic pump, if it only happens when operating hydraulics.

Or it could be the infamous injector pump dieing a slow death. Mine behaved this way for a while. Then it started to run uncontrollably wide open. Your hours are right about where mine were when my injector pump failed.

I'd check the flow of fuel at the point where it enters directly into your injector pump the next time it happens and make sure it is as expected. This will either confirm or deny that it's related to fuel delivery (at least up to the injector pump).

I'd be surprised if it's exhaust or intake related. I would think those sorts of issues would be manifest from first turn on.

 

[TBDonnelly]

Now the plot thicken's-or-does it?

I've been concerned about wax, not ear wax, but the parafin kind that's in the diesel fuel. After the most recent occurence, just a couple weeks ago, when I limped the tractor back to the garage, I looked at the fuel bowl and it was only 1/2 full of fuel. This is when I decided to drain the fuel tank and replace the fuel filter with a brand new fuel filter. Were the fuel filters being plugged up with wax from the diesel fuel? I could not visually detect a waxy surface on the fuel filter. I had been soaking the fuel filters in kerosene and blowing them out with the air gun. Was this enough to clean the filters throughly? I took one fuel filter and heated it up in a pan of water to see if any wax residue would show up, after cooling the water down in the fridge I did not detect any wax residue.

Then there's the algae question. Had I developed these live growing organisms in the fuel tank? I could not detect any slime or foreign colors on the fuel filter. After draining the fuel tank completely and refueling with fresh fuel along with a new fuel filter I think I have eliminated algae as the culprit.

Responding to Gittyup is next.......

Don

 

[tlbuser]

Not sure what they use to control the fuel pump. With that said, check and clean ALL of the ground connections; ignition, battery, pump, etc. One of them is probably loose and/or corroded.