Oil & Fuel Fuel - Injectors - Pump

[sandybeach]

400 hour engine - has developed a problem with low power, smoke, louder-than-usual diesel "clatter".

Air filter and fuel filter were very cruddy, so I changed them. When I bled the fuel lines, it was weird .... it was like the air wouldn't all bleed out. On two of the injectors it would stop bubbling and push out just fuel - as if I succeeded. Then more air came out. This kept happening. It must have worked somewhat, because the engine started - but ran only at about 500 RPM, then soon died.

I called the dealer. On he phone blamed it on clogged injectors and/or a defective pump. When he got it in the shop, he found ... surprise! ... 2 clogged injectors and a third where either the injector was bad or the pump was faulty. He's still working on it (waiting for parts).

He blamed it on bad fuel: debris, including rust, and (of course) water. I find that strange.

• The fuel tank is plastic.
• The filler tube has the factory-installed mesh filter (which I clean frequently).
• I get my fuel in approved 5-gallon plastic diesel "cans."
• I pump fuel from the can to the tank using a battery powered pump. When pumping the fuel I never get the bottom of the can - where water & crud would hang out.

So I'm puzzled.

One problem might be that I get fuel from 3 different places: 2 convience stores that have deisel pumps, and the farmers' supply (which has off-road fuel). The convience stores are within 10 miles from home and the farmers' supply is 20 miles - and I'm only buying 10 gallons at a time. One last hazard is that I live in the cool damp weather of the Pacific Northwest - that might contribute to water from condensation in the cans and/or tractor's fuel tank.

This is going to be very expensive, so I need to prevent a repeat. I'm looking for ideas on procedures and possibly fuel additives.

 

[Harry in Ky]

Assuming that your problem is only related to dirty fuel(not dirty air) and you're concern is about repeat pump/injector failure? My first thought would be to replace the fuel filter unit with something more effective. I've never understood why(other than initial cost) compact and sub compact manufacturers insist on supplying tractors with such small and ineffective filter units. Just my opinion here, but I feel that the tiny poorly fitting, poorly sealed, thimble sized paper elements are next to worthless in actually cleaning fuel and eliminating contamination related pump and injector problems. There are any number of water separator type filter units out there. Any one of them will be more effective than what you have now. They are also larger so will require more space as well as a bit of "engineering" on your part to fit, mount, and plumb. If done properly, the end result will far outweigh the effort. Racor is a popular brand, but can be expensive, plus the replacement elements can be hard to find. CAV makes an effective unit, and is commonly seen on many tractors sold from the 60's through the 90's. Elements are affordable and available everywhere. I prefer filters with a glass bowl so water and other impurities can be seen without disassembly. The CAV can be a bit tricky to change/seal for the novice, but a little experience and practice goes a long way.
As for the fuel itself, I suspect you're doing all that's possible to handle it as cleanly and effectively as possible. Unfortunately no matter how careful we are, "stuff happens". The filter is the "last chance" and needs to be as effective as possible.

 

[TractorTech]

Ditto to what Harry said.
Racor makes filter/water separator combinations that may be easy to adapt.

 

[sandybeach]

Wow! That's a lot of good information. Thank you.

Right now the tractor is in the shop. The dealer replaced all 3 injectors. Replacing 2 of those made improvements in performance. Replacing the 3rd made no difference. The factory has authorized "tearing down" the engine to see what's going on in the 3rd cylinder. This doesn't sound good.

Meanwhile I purchased a filler funnel with multiple filters built-in. https://www.amazon.com/gp/product/B000SOFLL6/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

 

[Dieseltech]

The best way to help keep water out of fuel if condensation is the problem is to keep the tank full, especially when not in use awhile. When moisture appears on the outside of the tank that can be seen it's on the inside too because of the tank vent. When water sticks the injectors open a quick check is to remove the fuel line at the injector and crank the engine, if compression blows backward through the injector it's stuck open. Sometimes cleaning will save them, but if not new tips will be needed. Also be careful if aftermarket filter is used, I had a Ford compact awhile back the top flange was too short. It did not seal allowing dirt into pump and injectors. After I cleaned the pump it was OK, but the injectors needed new tips.

 

[Fawken]

I agree with the OP that 400 hours is too soon to have dirty injectors, but also a lot has to do with how (and how often) the tractor is used. Try to give it a good 20 minute, high-load, med RPM run every few days. Inspect your sediment/filter bowl often, and don't be afraid to open the petcock and drain it if the tractor does sit idle for a week or so- especially in winter. If the problem still recurs the pump timing may be a tad off kilter.

 

[Coyote machine]

Injectors and injection pumps for diesel, (and gas engines) are very close tolerance specs, which translates to they will not tolerate dirt or any particulate matter for any length of time. Hence the failure of 2 out of 3 injectors. Your fuel tank is suspect, and should be completely drained and cleaned. Adding a Raycor or other high quality fuel filter can be beneficial, but you need to find out what the source of the problem is so it can be stopped from occurring again.
I would find one place to get fuel from, and if possible store it on site in a sealed fuel tank of whatever size your budget and space will allow. Three different sources make it hard to narrow down where the contamination is coming from. Lack of use can cause problems, depending on how long the tractor sits between uses. Once you get it back, before shutting it off each time bring it down to idle and let it run a few minutes to 'cool' down before shutting it off. This will allow things like the injection pump and other worked engine parts to drop heat before just shutting it off at full heat. This is better for critical parts to excess heat dissipated.

I'm curious why the dealer thinks you would have all the things he mentioned in your fuel system?
And for future reference, injectors can be pop tested, cleaned, and or rebuilt as needed. I would be concerned that whatever is/was causing your problems is/was passing through to your injection pump and jamming your injectors.
You said 'air and fuel filter were very cruddy'. Why? What work are you doing that both would be 'very cruddy'?
Are we talking about the outer visible paper of the fuel filter, after removing it from the container? Is there a sight glass bowl on your rig? If so, was there sediment/rust/water present at the bottom of the bowl?

This tractor is under warranty, yes? If so, why is this going to be an expensive issue?
What is the current thinking on the 'dead' hole? If factory authorized teardown, what is their reasoning as to what are they looking for? Ask the shop to document everything with pictures, and if they won't will they let you do so?
Post back....