It has been almost two years since my RAM Auto-start days. I can no longer remember the details. Today, SeanReit came by and we ran that SimJet 1700 that he has with a RAM auto start ECU. I aborted the first start when I clearly heard, just after Sean pressed the run button, the propane valve pulsing, releasing start gas (Powermax). It does this for a few seconds and then engages the starter motor. Then on the second cycle of the starter motor, the solenoid releases more gas, the glow plug lights and she autostarts just fine every time. But my question is this: why in the heck does it open the gas the first time for? Just to waste gas? There are no RPMs and no fire to the plug yet, so it is a waste of time. Sean also said that is the exact same way that his 1000 works. I must have had earlier auto start software cause I do not remember this. Any clues out there? Thanks.

It purges any gas currently in the lines, so that when it does for the second time a full amount gas is supplied to the turbine.

OK. This was a recent addition to the software right? I don't remember mine doing that.

I don't know if it was a recent addition or not, but thats how my Ram 500 works, and it is one of the later ones.

I have an early 500 that does not do it. Must have been something added as it evolved.

[QUOTE][. Then on the second cycle of the starter motor, the solenoid releases more gas, the glow plug lights and she autostarts just fine every time. But my question is this: why in the heck does it open the gas the first time for? Just to waste gas?


Just be grateful that it starts. Those of us who are long-time RAM owners do not quibble over small details like this. We are overjoyed to push the RUN button and actually have the engine run. It was not always thus.

I was told that the reason was to purge the lines of any liquid gas that may have been in the line. When it did the second cycle only gas should be in the line. Does it need it, probably not. My P-120 starts perfectly every time without going through that process. And I never saw the start reliability increase with this sytem. It still depended on the right pressure in the gas cannister, the right temp, the right battery voltage, the right parameters set, and the current phase of the moon.

Thanks guys. Looks like there is a consensus.

Hi there

The gas purge is a feature of the C02C version software.

It is actually purging air from the gas circuit to ensure gas only, reaches the engine during the start/ign phase, resulting in an instant light-up.

All the X series engines have it.

Regards to all those dedicated RAM users out there. We'll have the last laugh, you wait and see.

Ian McLaren

Still the RAM agent in the UK.

LOL. So true ! I'm now using a FADEC on my RAM 500 for that very reason.

The reason that the engine wouldn't start properly was probably because you couldn't set the parameters correctly in the dark.

Put a backlight in the EDT and try again.

I have never seen a problem yet, that wasn't caused by "finger-trouble" of some sort.

And I've picked a few FADEC's out of smoking craters too.

Then you've lived a charmed life !

Sure , I've had my moments. But's it's not over yet.

I saw PLENTY of RAM problems caused by non-finger trouble. I went through a BUNCH of 1000 rear bearings. You are indeed living a charmed life!

Remember I was talking ECU's

Bearings? OK I have seen bearings fail, but then they were caused by wet starts caused by...............incorrect ECU settings.

Oh, and not only on RAM's either.

There's always an answer. And not always the one you want to hear, or prepared to listen to.

Sure I had problems with the old (air-start) ECU's being "noisy" over here, on 35MHZ, but once that was sorted they were, and still are,fine.

As to the Remote starts I can honestly say that out of 35 engines I sold with Auto start, only one of them had any problems that I could attribute to a fault, when an O ring came off the starter and was eagerly eaten by the compressor. The starters were made by a third party at that time. Production of these eventually went in-house, and I never had, or heard of any others.

Of the three ECU's that I had returned as faulty, two of them had parameters set that would have started a Rolls-Royce Olympus. When reset to the correct numbers, they worked fine. And the engines survived the assault on them.

The other one, had been modified by the customer, before he had even tested it, following "advice" he had gleaned from RCU and other forums, from all the "experts"out there.

Again, once it was reverted to standard, it worked just fine, and still does.

Another customer has asked for his RAM ECU's for both his engines to be upgraded and returned, to replace his FADEC units.

I wonder why?

Charmed life? Or just prepared to sit down and read the manual a few times in order to "fully understand" as suggested in the early pages.

Not trying to start a battle. Just levelling up the battlefield a little.

Well, I'm glad you've had good experiences with all of your RAM equipment. I won't go on about all the problems that I've had with RAM 500 SN 070 because it's a very long tale but I will comment on at least my B version ECU.

I have seen it start the engine nicely and have it idling in 20s. Great ! For every start like that I've had 10 mis starts. IMO opinion this ECU wants to do everything RIGHT NOW and if any part of the start sequence is slightly out of step it does not work. The much more gentle , deliberate autostart sequences use by other motor and ECU manufacturers is a lot better.

When I finally sorted out the mechanical and combustion chamber issues with my RAM I also switched over to a manual start FADEC. Trouble free starting EVERY time.

Hi Marc

I think you hit it on the head when you mention the softer starts achieved with other engines.

If you go by the standard out of the box parameters, the RAM engine goes off like a firework. Flash, bang, whoosh, and it's off and running with flames and stuff pouring out the back.

With a little bit of TLC and a bit of patient adjustment, I can get my engines (2 RAM 1000R's and a 500R) to start exactly like a Jetcat, or similar, and in any weather. Imitation is the sincerest form of flattery.

All it (usually) has taken to achieve this, has been a few test runs on a bench or even in the model.

You must have the touch ! I've tried everything ever written about how to get consistent starts and it still doesn't work as well as I would like . If atmospheric conditions, battery voltage, gas pressure changes etc.. it screws up your finely massaged parameters. I just got tired of the agravation and switched to something that works for ME.

Two things I did make sure of.

Battery ALWAYS charged before use. Regardless of how short the flight, or the run. And again always after about 6-8 failed starts during testing or setup.

Gas parameters set to the absolute minimum required to get consistent light-ups. As a result I can usually get minimum 4 starts on one fill of gas. In effect very low setting.

All it has to do is lift the temp at the probe to 120 C and if the RPM is in excess of 8K then ramping should occur. Main reason why the battery has to be spot on. If the 8K isn't achieved then a failed start is highly likely.

Add to all of this the ECU threshold being set too high, and the voltage dipping into the ECU LO area, and all sorts of things can happen.

The ECU battery is really only hammered during the start sequence. After that it runs the pump and the electronics which take very little out of it. The ECU threshold can then be set at a sensible setting which will allow the starter to operate without pulling the volts down too far.

Excuse me if I am going over old ground here, but it is what I have had to do for the last couple of years to ensure a peaceful life.

Maybe someone out there will gain something from it

Best regards

Ian

How can you modify the function of the starter to draw less current ? As far as I know, this starter hammers on full go whereas other ECU's have PWM on the starter and bring the motor up to starting speed slowly ?

Hi Marc

I seem to remember a device used by the model train fraternity, which employed a thermistor on the drive motor which automatically slowed the motors to a standstill and speeded them up gradually on application of power.

I wonder if something like that could be, or even has been, employed to perform a gradual increase in speed.

Perhaps some of the electronics people out there could confirm whether that would be an option.

Food for thought.

I simply set the START PW to a low setting, and allowed the engine to catch up with it gently. Minimum of fuss and no flames at all. It would take all of 20 secs max from Start init, to RUNNING.
But , that is too long for some people. Result HI Start PW and flames, and a saving of 5 seconds or so. No point at all.

My task for the next week or two, is to check over and re-calibrate several engines returning from the World Jet Masters in South Africa.

Horror stories of every parameter available having been turned up to max, just to get the engines to start and idle, never mind trying to produce enough thrust to cope with 5000+ Altitude and 32 degrees C.

I'll keep you posted.

Ian

Thanks for the input Ian. I'll wave out the left window tonight on my way to Frankfurt !

Hey Marc

I'll put really bright lites on my EDT so you can check my numbers

Happy Landings

Not trying to start a battle either and I certainly DO NOT want to kick anyone while they are down and re-hash the RAM problems. Again, you are either incredibly lucky with RAMs or you lead a charmed life indeed. I was a RAM rep for several years. Almost all of my experience was with the old Electrodynamics ECU, first air-start, then manual electric start. Your assertions that the short bearing life was brought on by changed parameters or wet starts is folly. The old RAM stuff was not user settable for the ramp rate and none of this was cause by wet starts. The engines were well known to have a rear bearing issue, at least when the 1000 originally came out. This is an historical fact, not my opinion. I was flying these engines A LOT! Simply ask some of the other USA RAM guys from that time period: David Reid, Dennis Lott, Vern Montgomery, etc. And by the way, my limited experience with the Remote Start RAM ECU (I had one and a friend had a 500) was right before I bought my first TJT. I did indeed “read the manual a few times in order to "fully understand" as suggested in the early pages”. I was still a RAM rep and I assure you that I had a handle on the operation of that ECU, and guess what? We still had PLENTY of problems. I guess I was not charmed!

JockJet, e-mail me off R/C U or use a private message and I'll break down for you EXACTLY how many engines, what types of failure... all the data and then you can decide for yourself. There is only one conclusion that a reasonable individual can draw: there was a design issue with the engine. I hope that has been fixed.