Engine Intake Pre-Heater Questions

[m139h2otruck]

After getting the tractor home, looked into the pre-heater and why it did not fire. Have great spark @ plug as installed (looked through nozzle port). Have real good fuel flow when hose is removed from nozzle and solenoid valve is not stuck. Have no spray out of nozzle even if the pressure relief valve on pump is cranked up full. No return fuel flow out of return port of nozzle either. Pump appears to run correctly and under no pressure flows a lot of fuel. Removed nozzle from holder and cleaned with paint thinner and air pressure. Seemed to be clean and flowed air as best as I can tell. Any suggestions?

 

[m139h2otruck]

I need to add that the pre-heater setup looks just like the MF, just placed in different positions. The pump is on the left front of the engine, coil on left mid rear and the valves about in the center on the left, all right up in your face to work on. nozzle and plug are in the 90 degree turn on the rear with the fire drawn down into the intake. No restriction like on the deuce intake.

 

[acetomatoco]

I am not smart enough to figure out what motor you are talking about...Assuming a LDS 465-1A. But when you said it looks like a MF setup...I got quizzical. Can you put a pressure gauge in the nozzle hole and see if the pump actually builds pressure under a no/low flow situation... Do not put your thumb over the line to check it... Those units have always been a black hole to me anyway.. and when it gets really cold I have a little can of ether I use to give that little snort of go juice... Good batteries and 10 wt oil in the winter usually start most of the MFs anyway....have fun.

 

[m139h2otruck]

Sorry, I didn't mention that the motor is a Mack. Did in the other post on the trip home, so just skipped it on this one.

 

[m139h2otruck]

Calling cranetruck!! I know you have worked with and tinkered on the heaters for the MFs, any ideas?

 

[m139h2otruck]

Pics of heater parts.

 

[derby]

I have not looked at my Multis.cold weather start assist in any detail,but it seems to be very close to a fuel oil furnace.If you have proper pressure to the nozzle it will form a very and I mean very fine mist mixed with the air and a little spark ,wala ...flame thrower.I would assume the nozzle port is 1/4 the size or smaller than of a home unit.once you plug it it is better to replace it than try and clean it.At My old shop we would change them yearly.I will dig into mine as it is off the truck right now.and report any of my findings or other 2 cents!

 

[m139h2otruck]

Still waiting for cranetruck's input, HELP.

 

[M543A2]

On the multifuels the little valve body behind the nozzle can be taken apart and checked and cleaned out. This valve body has the fuel lines attached to it. I have done that to several, with good results. There is a little felt pad filter in them and other valve parts that can be cleaned to be sure they are going to function correctly. I cleaned the little filter pad by immersing in lacquer thinner and squeezing it several times to clean the gunk out of it. I do not know if your set up has this valve body or not.
Regards Marti

 

[cranetruck]

Still waiting for cranetruck's input, HELP.

Sorry, kind of skipped this thread after the engine was identified as a Mack.
I did write an article on the multifuel "flame heater", so if you have specific questions, let me have'm.

 

[cranetruck]

..... No restriction like on the deuce intake.

One problem I discovered was that with enough air flow, the flame is snuffed out. A wider manifold cross section is an advantage (=slower air speed). Still the flame heater has to be used correctly.

http://imageevent.com/cranetruck/flamedetector

 

[m139h2otruck]

I have already taken the nozzle out of the little "manifold" on the intake and tried to blow it out. It looks like an oil furnace nozzle with a fine mesh screen on the end and some sort of tail that looks like it controls the overflow or return. As far as I can tell, the whole system is very close to what the multis use, just mounted on the Mack.

 

[m139h2otruck]

Also, tried to run the heater with no cranking of the engine and with the spark plug out. There is just no fuel flow. Must be something wrong with the nozzle.

 

[derby]

Did you measure the fuel line pressure to the nozzle? You might have flow, but with no pressure it wont work.If the pressure is good replace the nozzle.