Oil & Fuel Kama 554 fuel return hoses, anyone know where to

greg_g · Mar 27, 2005

Re: Kama 554 fuel return hoses, anyone know where to

( OK guys....This is how these flame heaters work. )

Hmmmm....I don't doubt you believe that's how the duece and a half preheater works. But I'd really like to know if yours has an original multi-fuel engine, or if it's been professionally converted to 100% diesel.

Makes a BIG difference when you're talking about flaming fuel and diesel injector pump timing. Or flaming fuel and ignition timing.

//greg//

schmalts · Mar 27, 2005

Re: Kama 554 fuel return hoses, anyone know where to

Gregg, think about it, given a red hot coil it would only take 15 -20 drops of fuel to warm up the intake manifold some. That fuel will be setting in the lowest part of the return line of that splice, so a large supply is not needed.
If it injected fuel while cranking it would do nothing at all, we all know that liquid fuel will not burn in any engine, it needs to be a fine vapor or in the diesels case a fine mist.
I have started my tractor in temps down to 0 degrees by simp,y taking a propane torch and slowley waving it across the intake manifold for a few minutes until it was warm, and the thing fired right up when it condensed all that heat when i cranked her. The flame heater does the same thing but from the inside.

2000fxdl · Mar 27, 2005

Re: Kama 554 fuel return hoses, anyone know where to

I spent 14 yrs driving and working on dueces from 1972-1986 while in the Army. I always wanted one so I bought one from the Air Force . My duece, a 1985 model, (which was one of the last ones built) has a LDT 465 1C "whistler" Multifuel which is all original except that I adjusted the fuel compensator so the engine puts out around 200 hp / 425 lbs torque with 14 lbs of boost which is a bit more than the stock 134hp/305 lbs torque at 7lbs of boost. I only burn diesel but it is still capable of burning gas and jet fuel. The flame heater did not work when I bought the truck a few years ago, It does now after troubleshooting and testing it using TM 9-2815-210-34-2-1 which is only one of the 15 TMs I have on this truck. The flame heater and injection pump work totally independant of each other and the flame heater can only be safely used while cranking the engine otherwise it can start a fire...backwards towards the air cleaner...big time!!! All I was trying to say was the things do the same thing.....actually start a small fire in the intake manifold.

greg_g · Mar 27, 2005

Re: Kama 554 fuel return hoses, anyone know where to

( The flame heater and injection pump work totally independant of each other and the flame heater can only be safely used while cranking the engine otherwise it can start a fire...backwards towards the air cleaner...big time!!! )
My point(s) exactly.

Which is why I'm a bit doubtful if the M2A5 system is identical to the pure diesel Yanmar ThermoStart system I've been describing. Only thing that hasn't been concluded yet, is whether the Chinese pre-heater system is a Japanese clone. I know the engines are Isuzu-based, so there's a good chance the Chinese adapted the Japanese ThermoStart design.

//greg//

greg_g · Mar 28, 2005

Re: Kama 554 fuel return hoses, anyone know where to

( fuel will be setting in the lowest part of the return line of that splice, so a large supply is not needed.)

There is some logic to that, I guess. The operating principle being that gravity should have permited the ThermoStart supply line to partially fill as a normal course of (previously) operating the tractor. Compared to the standalone reservior though, I still have some doubts about consistent availability of fuel after extended idle periods.

( If it injected fuel while cranking it would do nothing at all, we all know that liquid fuel will not burn in any engine, it needs to be a fine vapor or in the diesels case a fine mist.)

Here's where I don't think I've gotten my point across though. Heat first, crank second. Do not confuse the pre-heater (see attachment) with the fuel injectors. The pre-heater warms up air with electricity, not cranking. The injectors atomize fuel - only by cranking. And if I gave the impression that raw fuel was introduced into the precombustion chambers, let me clear that up now.

If you already had "a fire" in the intake manifold, it would cause serious pre-ignition problems. The results can be compared to problems encountered with the indiscriminate use of ether or starting fluid; cylinders firing before the crankshaft is positioned for the power stroke.

What you've really got is something resembling a butane lighter flame heating up the air inside the intake manifold. Here's the sequence as best I understand it. When you supply 12v to the pre-heater, a coil something like a car's cigarette lighter begins to glow. The heat soon causes a spring to open a ball valve, letting in a tiny amount of diesel fuel from the supply line. As the diesel slowly passes through the ball valve - then the heating element - it burns something on the order of a pilot light or butane lighter. After a heating cycle appropriate to the ambient temperature, you can crank the engine. Each intake stroke sucks the now-heated air into the cylinders - sequentially. Once in the cylinder, it mixes with the (cold) atomized fuel on the compression stroke, and subsequently detonates to provide the power stroke. Removing 12v from the pre-heater allows it to cool sufficiently to where the ball valve spring returns to it's original position - and fuel to/through the preheater is stopped.

//greg//