With the recent availability of used RAM 750's I'm very interested in getting a straightforward definition of the different types of 750 that are out there.

I see the -F and the -P. I assume there are also air start and auto start, and electric start? Does the -P or -F mean anything in relation to the start method. Just a list of the different types would be hugely helpfull.

Thanks

The F version is the second generation unit that used an oil-kero mix, rather than having a separate oil tank as on the first generation. The P stands for Plus; it is an increased thrust version of the 750F.

As I recall, it is good for about 20 lbs of thrust, though my memory on this is a little shaky.

Any of these can be air start, electric start, or auto start. Mine, for example, is a 750F which was air start, but has been converted to electric start. It is still a 750F. How is that for confusing?

I think there was an auto start version also, the 750R, but I could be wrong about that. Maybe Carlos will fill in the missing details here.

Yes, i too am interested in perhaps purchasing one of the used rams that is priced to be a good deal but " how good of a deal is it??" How long will RTI be serviceing the engines? How long will the parts supply hold out? Also, does carlos have the ability to "turn up" an old ecu on a 750 that was turned down thus limiting the engine. Russ

Electro Dynamics made the Ram ECU's, and are able to reset them, as well as replace them. You can also up grade to a unit that can be set by the user.

Electrodynamics only made the original ECU type (pressure feedback), NOT the later auto start version (RPM feedback). Bob Price made those. The 750 and 750F were air start engines. Then, when the 1000 and 750P came out (the 750P is just a tuned down 1000, totally different engine than the 750 & 750F), they were capable of both air & electric start (manual electric). When the jump was made to the Price ECU, that's when they became auto start. At some point the "R" (for remote start, I think) got tagged on. As Brian pointed out, some people went and had their old style 750s modded to electric start, maybe even auto, but those were not originally like that.

For those who are looking for specifi answers from Carlos, may I suggest that you pse those questions to him in the RAM turbine clinic forum ?

Carlos is a very busy guy, and probably does not have enough time to browse through all of the posts in the main jet forum, but he does do his best to provide answers in the clinic. You therefore have a better chance of getting the answers you want if you post there.

Gordon

P.S. Andy, at Electrodynamics, does indeed still service and sell the original RAM style pressure reading ECUs.

One thing to consider is that even engines which share the same designation (F's, P's, etc) are not identical. I found this out recently while having some turbines serviced by Carlos. This makes servicing the engines a tricky task.

Also be aware that some RAM engines were manufactured with components known to be defective, specifically the turbine wheel. Apparently there was badge of turbine wheels that was shipped by Artes and later identified as defective. Rather than destroying the balance of the badge after getting a replacement order from Artes, they were installed in many turbines. One of them being mine. After Carlos identified the potential problem in my engine, I had it replaced by a new one.

As I recall, Carlos identified the potentially defective turbine wheel by looking for what appears to be an "erased" or "filed" Artes logo on the turbine wheel.

I hope this information will help.

Yes...there were quite a few changes that did occur over a three year period. The first 750s featured a seperate oil tank - then came along the fuel / oil premix and a mod to the 750 making it the 750F ( fuel / oil mix ). That remained pretty much it as the engine went except for some software changes in the compressor controlled ecu which was designed by Andy Low of Electrodynamics. A starter motor mod came next which could be fitted to the 750F but this required a new startbox and thus was born the 750F electric start. All this mean't was that instead of air start the motor could be started using a battery pack built into the start box terminal.

The next generation engine to come out was the 750P / 1000 version which featured 22 / 28 lbs of thrust. Note that the 750F cannot be converted to a P model as many parts need to be changed. The R version of the 750P and 1000 featured a new ecu designed by Bob Price. Hence was born the 750PR and 1000R or simply remote start. A number of changes B,L,M and the final version C02C were integrated into the ECU. If you come across a 750P or 500 with a C02C version ecu you will have the last model that RAM produced ( those are were very good designs and are in great demand on the used market ).

Dean Wichmann
( former RAM distributor )

Woketman,

The "potentially defective" turbine wheels that should have been replaced were installed in either the 750's or 1000's.

As a matter of fact, this is an interesting fact: The engines were designated as 750 or 1000 after their first run. If the engine was able to handle and deliver the output parameters of a 1000 then it was designated a 1000.

If the engine missed the 1000 parameters the designation was made depending on the engine performance. Thus we ended up buying "theoritically" the same engine as far as components. The only difference again, was the performance of the engine.

All,
To add to the confusion, the early Rams
(750 and 750F) had 6 burner tubes and
combustors. If you buy that type thinking
you got a deal, wait until you have it serviced.
If you buy one make sure it has the Wren
wheel as well as the 12 burners. My .02.

Johnny

Wait a minute Johnny. I did not know that Wren made any KJ-66 sized turbine wheels. Did they? Or id you mean Artes?

Rocketman,
Carlos has been my source of information as well
as Merton Moore of Moors Turbine. I had the old
Artes wheels in my Ram 750F that shredded
blades, been there done that. Not that Artes wheels
are bad, but not in the Ram configuration did they
work well. But to answer your question, yes Wren
makes the KJ66 wheel.

Johnny

The 750F was not the engine that was notorious for slinging blades. If you had an F that shed parts it was unusual. The 1000/750 P version was the one that slung blades, bearings, shed tail cones etc... As far as the RAM engines go the 750 F was the most reliable engine they ever built. The turbine wheels that had the problems almost always had bumps at the root of the blade, close to the hub. I have a picture of one somewhere I will post it if I can find it.

David Reid

David,
I have had two Ram 750F throw blades, I have
the Artes KJ66 in my hand now with a blade
missing that Carlos repaired at Superman 2002.
In 2002 my friends Ram 750 did the same thing
on start up. Talk to Carlos.

Johnny

I believe that many of the times that RAMs shed turbine blades were not the fault of the turbine wheel, but rather the rear bearing failing, then contact is made with the near by wall and well.... all hell brakes loose and you loose some blades. I'm sure some wheels did indeed fail, but most likely the rear bearing failing accounted for most of the ass-end blues for the 1000. Johnny, I did not know that Wren made any 66 wheels for them. Thanks for the clarification.

David, Kaptain Kaos flew down here for bidness on Monday. He is going to be in my driveway at 9:30 AM and we will then head out to Lumberton with Richard and the gang (not to be confused with Cool & the Gang!). Get Dennis & Vern and meet us there!!!

Mark,

I had two 1000's shed blades both kept running after the blade departed. It may very well have been a bearing failure both times.


Johnny sorry bud no need for me to talk to Carlos I stopped flying RAM's after the second dead stick one afternoon left me with a damaged Bandit. That and the fact that we went through 3 engines on one Bobcat at Superman 2001......and the list goes on. Good price or not I would not own another RAM even if you gave one to me.

WOW! Kept running after the blade went into the bleachers (sorry). When I had that 1000 blow in Isobar #2, it was at high throttle, running her up in the pitts for the last flight of the day, and just about made me crap my pants (it did make the guy holding the nose of the plane crap his!). It was more of an explosion than a bearing failure. VERY exciting! The only good to come out of it was that the local guys, after that Sunday afternoon, now ALWAYS listen when I say "please get in front of the aircraft while I run it up".

David, can you make it tomorrow?

Mark,

I can not make it tomorrow. 4 1/2 hours of driving each way and I have the Phantom stripped down right now refinishing a couple of areas before Florida Jets. I am also hoping to get the puttying just about done on an F-100 too.

Hey woketman that was serious but funny as hell about your engine blowing up LOL.
But i still think its the best engine when its running. Some guys think by changing manufacturers they are changing Ram LOL. I known some guys out there with mechanical background known better. As long as parts are available for simjet,jetcat
eta. There is parts for my ram 750/1000
Get the picture.

unKnown you sound like you know alot about turbine engine are you Rei or Alberth ???. your post make a lot of sense .

Believe you me guy, RAM engines are not the only ones that are shading blades. Some of the other brands are doing the same, but I will not mention brand names here.

This coming flying season will be an eye opener for everybody and some other brands of turbine start getting the amount of mileage/usage as RAM.

One question for some of you RAM bashers, if RAM was such a bad engine, why did one of the top name in model jets endorse it?. Apparently it must not have been as bad as some of you make it sound.

Hey...........Ghostrider,,,Your new kit is still waiting to be picked up here at the shop, did you get scared and go into hiding? If you are passing on this opportunity, please let me know....it's been a week since we talked.
Remember:
The bigger the toy, the bigger the boy!!

Strikemaster.............out

Im not a basher, but I think it has alot to do with location and buddies? And at the time they raised the bar from what was available. Just MO from what I have gathered.

Ben,

"One question for some of you RAM bashers, if RAM was such a bad engine, why did one of the top name in model jets endorse it?. Apparently it must not have been as bad as some of you make it sound."

Just like they endorsed JPX, which is now obsolete? Don't you remeber the full page color ads in RCJI with BVM and Chris Huhn holding the JPX engine(s)? Well, where is JPX now?

Just because BVM endorses a product, doesn't mean it's the best...it just the BVM opinion of what's hot at the time (and more importantly, whose sale will give them the largest return). Their touting of the SWB Mamba is a classic example....there aren't even any in the field yet!

Peter