I work on a variety of small engines in the 1-3 liter range. Isuzu, Perkins-Shibaura, Kubota, Lister, etc. On many of them it is an option on the same base engine whether to have IDI or DI. Some of them seem to start very easy and others like the Kubotas it seems a wonder they start at all. What would be the reason for ordering one or the other on the same engine?
Yair . . . Good one Birken Vogt this should be an interesting thread. Apart from the Caterpillar system I had never encountered Indirect Injection until the first crop of Japanese diesel pickups arrived on our shores. I understand to (some extent) it made the diesel more acceptable for automotive applications by allowing higher RPM and reducing the characteristic diesel rattle. I was horrified when I bought a Navara ute only to find Nissan recommended fifty hour oil changes . . . my whole life had been structured around two hundred and fifty hours for diesels. I did a bit of investigating and found soot in the oil was the issue and fitted a centrifugal filter and took the hours out to one hundred with out any ill effects. Some folks may remember the early Toyota Landcruisers and 6000 trucks had a centrifuge built into the tappet cover . . . most people didn't know what they were. Cheers.
Direct injection is aprox 10% better fuel economy due to no heat loss in the prechamber to the coolant like IDI. Also they start right up without glo plugs so less battery and electrical issues to deal with. IDI has less knock, cheaper to build since the injectors have one hole and don't need to atomize as well and burn bad fuels better. Water can make it though an IDI injector and it might blow the tip off a DI injector due to the tiny multiple holes in the DI. IDI is meeting new emission standards that DI is having trouble meeting on the smaller engines.
I think the pre-combustion makes IDI's quieter, i don't know by how much though. Might be a consideration for generator applications. Strange that you the botas struggle to start. I have no experience with IDI Kubota's, but have messed with a few 3 cylinders in equipment and they start and run like tops. Well there was one that gave me fits. Tried to help a neighbor with a Kubota b26 that would idle fine, but once he started moving dirt with the loader it would start spitting and sputtering. I'd bleed the fuel and it'd would smooth out. I never did see any air bubbles. Then he'd start using it and it'd start acting up agian. I ran out of ideas and winched up on his trailer for him. Dealer found the fuel tank half full of gas. I have 3 of the exact same yanmar engine in different pieces of equipment. The oldest one if it gets a whiff of air in the fuel it takes 20 minutes of bleeding fuel and cracking the injectors to get it to run again. Between the pickup tubes falling off in the tanks and the tank splitter and gauge switches being on opposite sides of the seat it happens kinda often. :Banghead One of the other ones the gauge is under the seat :bash, and the one time it's been run out fuel i put 5 gallons in and it kicked right off. Haven't managed to run the third one out fuel, yet, with only one tank and better fuel pickup design. I'm sure one of us will manage it. ointhead
Amongst my diesel machines I have a 1994 Peugeot 405 car with an IDI, turbocharged and inter cooled engine. It runs like a clock and has 412,000 kilometers on it. It has plenty of power and is very economical. The reason I bought this older car secondhand is because I have a good supply of used vegetable oil and my research found that this type of IDI diesel with a Bosch injection pump and this motor in particular runs well on a diesel/veggie oil mix. After putting nearly 50,000kms on this car myself using a 50/50 diesel/veggie oil blend I have to say it works well and has saved heaps on fuel costs. Considering the mileage and age of the car it's been really reliable as well. Goes great on long trips, it's really comfortable and eats hills like they weren't there. I have the same engine minus turbo and inter cooling on my JCB compact backhoe and it's been really economical as well. Unfortunately it looks like the simple injection pump diesels have been superseded by common rail DI diesels with expensive components & computer controlled with plenty of sensors to fail and give obscure fault codes. I'll be keeping my old gear until I get my solar powered electric vehicles and machines AusDave
I have an IDI Kubota in my 1994 skid steer. It needs the glow plugs to start even if it's 30 deg. C deg's. outside. Once it's warm it will start back up but if it's -30 C even plugged in all night can be a struggle to get going and I have 2 batteries. You need the glow plugs on for about a minute and half or more and often have to do it again because it didn't start. My 1965 MF135 with Perkins AD3-152 direct injection will start with just thermo-start down to about -20 C. as long as I can get it to spin over fast enough. In a couple rare cases when it was really cold and I needed it without being plugged in, I gave it a small shot of ether and it started. It's nice because you can turn the key without activating the thermo-start which would be a real bad thing. The Kubota in the skid steer is a darn good engine but I have heard they have such tight tolerances ether is the last thing you ever want to use on them. The 3204DI in the Cat with the 3 ring pistons starts super easy too. Nice sunny day slightly below freezing will start right up no ether or anything. The direct injection is more fuel efficient. The Perkins especially sips fuel.
Yair . . . Welder Dave. I hear you. It doesn't get very cold here but it amuses me to see the modern engines struggling to fire on a frosty morning and some times needing some ether assist (I prefer to use gasoline fumes) and yet the "Standard" four cylinder in the Fergi 35 fires right up. I have a Mazda pickup and unless it has areal good battery it will not start in the cold . . . I'm told it has to roll over twice for the engine control to "read the cam". Cheers.
The Standard Motors 4 cyl diesel in the early ** 35's was a notoriously bad cold starter and even the early Perkins with indirect injection was a huge improvement. I've read there's ways to hook up different glow plugs to make a Standard diesel easier to start. I've heard people say Perkins are hard to start in the cold too but I think if they are, they need some maintenance.
WD40, Lanox or any other type of penatrating oil in a spray can is far better to use than ether. This info came from a desiel injection guru.
Yep, was introduced to the WD40 religion when working on the tugboats... a good alternative when starting Detroits as they don't get addicted to it like they do ether.
I thought I read that WD40 is a different formulation now and doesn't work as starting fluid like it used to?