Looking for MA-1A Huffer Cart Technical Manuals

[soconnoriv]

Hi all,

I've had an MA-1A Huffer cart for a while now and I'm finally getting around to working on it. Only problem is that nobody on the Internet seems to know where there are Technical Manuals for it.

Anybody here familiar with these machines? My main problem is that there seems to be a stuck relay or a bad connection somewhere. I'm getting power from the batteries at various places/connections throughout the machine, but am not getting any power to the control panel. Looks like there is only one breaker for the entire machine from what I can see, and it's not popped.

Sounds awesome when I jump the starter motor and turn the engine over for a few seconds, but that's about all I can get it to do! What I really need is a wiring diagram!

Any help is appreciated!

Not mine, but here's what it looks like:



Thanks
-Steve

 

[Jericho]

May you have been NAVY , In the Air Force we used HUNDREDS OF THEM , most had the 71a gas turbine . We called them Plooshes for short, because when you stretched the hose out and loaded air down the line to flush it PRIOR to attaching it to an aircraft it would make a Plooshe sound. The engines were maintained by the Propulsion Flight ( Jet Engine Shop ) until well into the 90s .Iam assuming you have checked the batteries. The start sequence is simple really , Check your start switch relay , check the intake and exaust micro switches , they are put into run mode when the intake and exaust covers are opened . They are easy to see. use a PSM6( multi meter) to confirm voltage from the start swith thru the fuse and relays to the starter. The gas turbine also has a three speed switch on the fuel control, it senses RPM as a function , start, on speed (governed) and Over speed. one WARNING ,they are very noisey, use ear protection, Although they were usually used until failure they did have life limits and schedualed inspections using the Phase Isocronal Card Deck system , IF YOU SHELL OUT AN INDUCER OR EXDUCER AT OPERATIONAL SPEED THEY ARE LIKE A GRENADE, SHRAPNEL AND ALL, they turn at a very high rpm , oh and did I mention they GULP jet fuel T.O. s. may be hard to find , The Air Force historicly SHREDS , DESTROYS unneeded T.O.s , they were not as a rule put out for general public use unlike Army manuals But let me look around, My son was an AeroSpace Ground Equipment," AGE" mech and I was A Jet Engine "Jet Mech" , we both worked them , Ill pick his brain for you also

 

[Jericho]

I retired in 1994, was a small gas turbine shop Chief in the mid eighties doing repair on these, Seems to me the T.O. number was 2G-GTCP-85-70a , it breaks down as Aircraft , Ground support, Gas Turbine Compressor Powerplant, 85- 70 a model. Air Research made or remanufactured most of these.

 

[soconnoriv]

May you have been NAVY , In the Air Force we used HUNDREDS OF THEM , most had the 71a gas turbine . We called them Plooshes for short, because when you stretched the hose out and loaded air down the line to flush it PRIOR to attaching it to an aircraft it would make a Plooshe sound. The engines were maintained by the Propulsion Flight ( Jet Engine Shop ) until well into the 90s .Iam assuming you have checked the batteries. The start sequence is simple really , Check your start switch relay , check the intake and exaust micro switches , they are put into run mode when the intake and exaust covers are opened . They are easy to see. use a PSM6( multi meter) to confirm voltage from the start swith thru the fuse and relays to the starter. The gas turbine also has a three speed switch on the fuel control, it senses RPM as a function , start, on speed (governed) and Over speed. one WARNING ,they are very noisey, use ear protection, Although they were usually used until failure they did have life limits and schedualed inspections using the Phase Isocronal Card Deck system , IF YOU SHELL OUT AN INDUCER OR EXDUCER AT OPERATIONAL SPEED THEY ARE LIKE A GRENADE, SHRAPNEL AND ALL, they turn at a very high rpm , oh and did I mention they GULP jet fuel T.O. s. may be hard to find , The Air Force historicly SHREDS , DESTROYS unneeded T.O.s , they were not as a rule put out for general public use unlike Army manuals But let me look around, My son was an AeroSpace Ground Equipment," AGE" mech and I was A Jet Engine "Jet Mech" , we both worked them , Ill pick his brain for you also

That's awsome to hear that you worked on them and that there were so many! Looks to me like the battery voltage isn't getting that far. I'm getting 24 volts up to the starter relay and a few places here and there, but not much further than that. It doesn't seem to be making it's way to the control panel, everything on it is dead.

I appreciate you asking your son for more info. Manuals are impossible to get, so word of mouth is all I have!

One big question for you: Does the box/housing of the turbine lift off of the cart?? It seems that it's not held down by anything other than a few bolts and also has hoist points on top.

Here's a pic of my data plate:



Thanks!!!

 

[soconnoriv]

I retired in 1994, was a small gas turbine shop Chief in the mid eighties doing repair on these, Seems to me the T.O. number was 2G-GTCP-85-70a , it breaks down as Aircraft , Ground support, Gas Turbine Compressor Powerplant, 85- 70 a model. Air Research made or remanufactured most of these.

Just checked my data plate. It matches exactly what you said. Too bad Garret doesn't offer support for these anymore. Airesearch doesn't even have a website. Must've been stopped long ago.

Do you know if the turbine housing box lifts off of the cart? I can't seem to lift it easily, but it looks like it was designed to lift right off after disconnecting a few things.

Thanks!

 

[Jericho]

We referedto the as APUs as well Auxillery power Units , and tiny turbines , The turbing is easily removed, Theses were manufactured when every thing aircraft related was built and maintained the same as your assigned aircraft , In the early days when ever we defueled a jet,could have been 10000 pounds or 2200000 pounds of jet fuel, we treated it as contaminated, and it was used to power the AGE equipment , MA1As.(air) MD -60s (Electricals) , Hydro carts (hydraulic power), NF 2 s Light (All,s ) -Hf 1,s and 2s, (heaters) various A/C unts , some big enough to cool 747s . It was all made for the USAF and seldom seen in the civilian world of aviation, All high quality and complex, NO ONE stocked parts and the USAF normally had no sales legal contracts with the manufactures, Tech Data was carefully controlled and every single T.O. was signed for each time it was used on a hand receipt, After accounting if excess they were shredded by the TODO tech order duty Officer an NCO . The Turbine is held in buy aircraft style mounts and is removed by two airmen in about forty five minutes, The cannon plugs are simply loosened and a few wires disconnected , pop the mounts , tail pipe v band clamp and attach a sling and out it comes , maintaenace was performed in a purpose built roll over turbibe stand, then testing was done after maintenance in a Small turbine test Cell/Stand , it had mounts , loading hoist, rail, chainfall and control panel as well as fuel cell, neat little unit . Parts will be near impossible to get, although the unit was used foe other applications, a near dirivitive was used in the C -130 Hercules APU /GTCP 397-71A located near the wheel well of the main gear. Thermocouples(pyrometer, Three speed switches, Fuel controls, Starters , Ignitire, Combustion can, Fuel nozzles, All easy to change, just don't think you will find them . I am sure they are well out of production, We had trouble getting them in the late eighties let alone now, Biggest problem was that there wasn't a lot of money in producing spares for a 40 year old system, They just ran and ran and ran , We welded up combustion cans that could have a 80 % loss of parent metal , meaning 80% of the original can surface could be repaired area .

 

[Guyfang]

You know, it wouldn't hurt to give Garret a call/email. They were very good to me when I needed some info on a MUST. They did not have to help, but did because they wanted too.

 

[Jericho]

The start relays at K16 and k17. Near the fuel control test ports also know as the salt and pepper relays your looking for power thru the relays. They control the start of the start cycle. Once rotating the Three speed switch kicks in around 25 percent rpm opens fuel solinoid , supplies ignition, you should hear a snap snap snap as the ignitor fires then it acts again around 95% to control steady state operation. Then limits over speed at about 102 / 105 % rpm to prevent over speed. Ignition excitor has 24 to 28 VDC going in , 20 thousand volts out to ignitor . if you test by laying plug out side combustion case boss. It was very common. But. Be careful 20 k volts will kill you. Always ground ignition lead in removal to case to discharge ignition J box ( capacitive excitor box ) my son is in AZ at the moment TDY. He is back at the end of the week. He thinks he still has a tech School study guide on ploosh operation and trouble shooting. It’s also color coded you could trouble shoot most common faults with it alone. I’ll let you know when he finds it. Andy

 

[Jericho]

Guyfang is correct. They may help you and just might have an old TO around. Historically they replied to official calls. We were billed at the wing level at an hourly rate , by the end of Viet - Nam garret had no more GTCP tech reps at any AFB s for that unit I never saw it used in any civilian applications. It just used too much fuel and was expensive to maintain

 

[soconnoriv]

The start relays at K16 and k17. Near the fuel control test ports also know as the salt and pepper relays your looking for power thru the relays. They control the start of the start cycle. Once rotating the Three speed switch kicks in around 25 percent rpm opens fuel solinoid , supplies ignition, you should hear a snap snap snap as the ignitor fires then it acts again around 95% to control steady state operation. Then limits over speed at about 102 / 105 % rpm to prevent over speed. Ignition excitor has 24 to 28 VDC going in , 20 thousand volts out to ignitor . if you test by laying plug out side combustion case boss. It was very common. But. Be careful 20 k volts will kill you. Always ground ignition lead in removal to case to discharge ignition J box ( capacitive excitor box ) my son is in AZ at the moment TDY. He is back at the end of the week. He thinks he still has a tech School study guide on ploosh operation and trouble shooting. It’s also color coded you could trouble shoot most common faults with it alone. I’ll let you know when he finds it. Andy

Awesome, great info. Looks like the intake door microswitch was sticking open on mine. Got it working and now everything is getting power. Starter seems to work too, but my battery started dying at that point. Got it on charge.

Lots of good info you've got there. Great to know. Hopefully this week I can have it up and running!

 

[soconnoriv]

You know, it wouldn't hurt to give Garret a call/email. They were very good to me when I needed some info on a MUST. They did not have to help, but did because they wanted too.

I'll try and give them a call tomorrow. That's a real surprise to hear that they still support something that's so old. Hopefully they won't mind answering a few questions.

Thanks!

 

[Jericho]

The micro switch is a service able unit. Usually a little mIL-L-7808 turbine engine oil will free it up. Don’t get it on your skin is is a known cancer causing agent , lol glad I could help. Usually the first thing to look at is the micro switches I’ll still see if he can find the data

 

[Jericho]

Two more useful points ensure you have s fire extinguisher hand. If you have a post shut down combustion can fire. Do not discharge extinguisher intake or exhaust. Kill the fuel and motor the turbine over until the fire is extinguished. Worst result is you may fry starter. If you hit it with a FE you will thermal shock the inducer/ exducer and it’s toast !! Do use regular motor oil in it. Use Mil - L - 7808 or 29518 Reg oil will not suffice it will seize !!!!

 

[eatont9999]

Please post a video once you get it running!

 

[Guyfang]

Two more useful points ensure you have s fire extinguisher hand. If you have a post shut down combustion can fire. Do not discharge extinguisher intake or exhaust. Kill the fuel and motor the turbine over until the fire is extinguished. Worst result is you may fry starter. If you hit it with a FE you will thermal shock the inducer/ exducer and it’s toast !! Do NOT use regular motor oil in it. Use Mil - L - 7808 or 29518 Reg oil will not suffice it will seize !!!!

Jericho, I think this is what you meant. And yes, this crap is not what you want to get on your skin. Sadly, no one warned us about it, until I had worked with it for several years. I used it in the D424A 150 KW Turbine gen set, in Patriot ADA.

 

[Jericho]

Yes thank you. It had been a long day. And yes 7808 causes cancer. Used to swim in the stuff we all regularly sucked the stuff up the Joap ( joint Oil Anylisis Program ) sample tubes for oil wear trend analysis as well and spit it out. Mil-l -29515 sticks in my mind as the non synthetic turbine oil as well. AF really got hot on oil exposure in the mid eighties. Right after the agent Orange expousure guys started dying in large numbers We had loads of older NCO s getting rare cancers and dying MEK.( methyl ethyl ketone) MIL-L-5606 Hydraulic oil has the same carcinogen additives as well as any number of the cleaning agents and turbine engine gas path cleaner W e routinely were exposed to dioxins . Even jet fuel has been conclusively been shown to cause cancer and immediate hearing loss . Reference studies done in Australia’s new zealand and the United Kingdom

 

[soconnoriv]

Two more useful points ensure you have s fire extinguisher hand. If you have a post shut down combustion can fire. Do not discharge extinguisher intake or exhaust. Kill the fuel and motor the turbine over until the fire is extinguished. Worst result is you may fry starter. If you hit it with a FE you will thermal shock the inducer/ exducer and it’s toast !! Do use regular motor oil in it. Use Mil - L - 7808 or 29518 Reg oil will not suffice it will seize !!!!

I called honeywell tech support, they had no resources or any support available for that model. Seems that the model I have is so old that it's been unsupported for quite a while.

Other than that, I was able to find out a few more things with a bit of troubleshooting.

For one thing, the fuel pump works, I can hear it turning, but no fuel comes out of the nozzle line when I hit the start button.

Other prob is that the igniter doesn't tick when using the start button, but works fine when I supply power to it directly.

I also checked the oil filter and found that there was no filter there!! Just an empty bowl filled with oil! So now I need to find a filter for it.

The one thing that worries me, is that there is an oil pressure switch mounted near the ignition unit. I disconnected the line to make sure it was getting oil, but no oil came out! Maybe this has something to do with the filter missing?? I don't want to keep motoring it without oil pressure! As for the oil tank, it's got plenty of 7808 oil in it.

Thanks again for all the help, you and a few other people are the only ones left that know a thing or two about these!

 

[Guyfang]

I called honeywell tech support, they had no resources or any support available for that model. Seems that the model I have is so old that it's been unsupported for quite a while.

Other than that, I was able to find out a few more things with a bit of troubleshooting.

For one thing, the fuel pump works, I can hear it turning, but no fuel comes out of the nozzle line when I hit the start button.

Other prob is that the igniter doesn't tick when using the start button, but works fine when I supply power to it directly.

I also checked the oil filter and found that there was no filter there!! Just an empty bowl filled with oil! So now I need to find a filter for it.

The one thing that worries me, is that there is an oil pressure switch mounted near the ignition unit. I disconnected the line to make sure it was getting oil, but no oil came out! Maybe this has something to do with the filter missing?? I don't want to keep motoring it without oil pressure! As for the oil tank, it's got plenty of 7808 oil in it.

Thanks again for all the help, you and a few other people are the only ones left that know a thing or two about these!

The highlighted problems are interrelated. I have never worked on this set before. BUT, my D424A was a turbine, and it's probably about the same thing. I do remember that when I hit the start switch, that the fuel pump would kick on, (you can hear it) the fuel Solenoid would also kick on, (you could hear it) that lets the fuel go into the fuel nozzle/burner can. Shortly after that, the igniter would fire off. I do seem to also remember, that if the solenoid DIDN'T open, the igniter would NOT pop off. It was in series, so if one didnt work, the other didnt work. I also remember that if I had no fuel PRESSURE, the pump would run, but the igniter would NOT pop off. There was a function on the D424A that purged the fuel lines to atmosphere, before allowing the fuel system to apply fuel to the Nozzle. That was to clear old fuel from the system. And I know that if I had no OIL PRESSURE, the set would NOT start.

Jericho,

I once saw a D424A destroy itself in about 90 seconds. A very stupid, (and it pains me to admit a WO, ) put 15W-40 into a gen set, because, (oh how this pains me to remember the words) "Oil is oil!" I ran over to try and stop the whole deal, but was just too slow. 90 seconds. A new, rebuilt $255,000.00 engine, sent to turbine heaven.

 

[soconnoriv]

The highlighted problems are interrelated. I have never worked on this set before. BUT, my D424A was a turbine, and it's probably about the same thing. I do remember that when I hit the start switch, that the fuel pump would kick on, (you can hear it) the fuel Solenoid would also kick on, (you could hear it) that lets the fuel go into the fuel nozzle/burner can. Shortly after that, the igniter would fire off. I do seem to also remember, that if the solenoid DIDN'T open, the igniter would NOT pop off. It was in series, so if one didnt work, the other didnt work. I also remember that if I had no fuel PRESSURE, the pump would run, but the igniter would NOT pop off. There was a function on the D424A that purged the fuel lines to atmosphere, before allowing the fuel system to apply fuel to the Nozzle. That was to clear old fuel from the system. And I know that if I had no OIL PRESSURE, the set would NOT start.

Jericho,

I once saw a D424A destroy itself in about 90 seconds. A very stupid, (and it pains me to admit a WO, ) put 15W-40 into a gen set, because, (oh how this pains me to remember the words) "Oil is oil!" I ran over to try and stop the whole deal, but was just too slow. 90 seconds. A new, rebuilt $255,000.00 engine, sent to turbine heaven.

I think you're right on the money, especially with the oil pressure statement. I just got off the phone with a guy that overhauls these. He said that every symptom that i have is related to the oil pressure switch. After I told him that it's sat for a while, he strongly suggests that it is the problem. He also explained to me that there is a push-button style primer pump on the oil control unit. I had no idea what it was until he explained it to me! Sure enough, the pump seems to work!

He's also got hundreds of each part in stock for it! Looks like I'll be buying some filters and o-rings from him soon!
That really sucks to hear how your D424A self destructed like that. I'll be putting nothing other than 7808 in this machine for sure!

 

[Jericho]

Positive indicated oil pressure IS needed to complete light off, having said that , on your filter , there are two types the old style was a screen and spacer type that was cleanable, a series of mesh screens one on top of the other in sequence, you stripped them down chucked them in the ultra sonic cleaner for a few hours and restacked them , J 57 -59 W jet engine was the same , I believe those were all gone by the late eighties, the new style was a steel screen cartridge throw away . How high was the rpm going on your start attempts, Before the fuel solenoid allows fuel to the atomizer fuel nozzle it has to hit the first step on the three speed switch. DO NOT AS GUY FANG CORRECTED, USE REGULAR MOTOR OIL< it cant take the heat or the rpm ! I am amazed but happy for you that your found parts , Fuel control for it used to run UNCLE around $18.500.00 in 1992 , REBUILT, by depot, there were no new production controls by then , but don't be scared the price Charged by the Air Force Depot at San Antonio to the Air Force .