Michael Boland Posted March 24, 2007 Share Posted March 24, 2007 Having just purchased an RCV 120 SP I was dismayed when it failed during run in. Returning the motor to the factory from Australia was a $70 exercise, and the motor had apparently lost a tooth on the pinion. The response from RCV was exellent, fast turnaround, and new motor sent back and recieved in just over a week.I am wondering how many people out there have had experience with the 120SP and if so how was it? Good , bad, indifferent?It just seemed odd that I was a recipient of one of those "never seen that before" problems and a public forum is the best way to confirm this.Any feedback appreciated. Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted March 24, 2007 Share Posted March 24, 2007 Hi Michael, i would like one of these SP series, the engineering is quite revolutionary to say the least. I have read several threads on the RCV engines on other sites and I have not come across your problem, what I have seen is the level of customer service seems very good. And I think you have confirmed it. What are you going to put the motor in, and how are you managing airflow around the cylider for cooling? Quote Link to comment Share on other sites More sharing options...
Tony Campbell Posted March 24, 2007 Share Posted March 24, 2007 I found RCV to be pretty upfront regarding any known problems with their engines. I had a crankpin let go in an RCV58cd and they said that their had been a batch in an earlier production run that were prone to this problem..... they replaced it without any problems at all. Finding a manufacturer that openly admits to being fallible and not immediately blame the customer is like a breath of fresh air.I have full confidence in the company. Check out their guarantee on their engines, you just cant get better than that. Quote Link to comment Share on other sites More sharing options...
Michael Boland Posted March 25, 2007 Author Share Posted March 25, 2007 As far as customer services goes RCV has it sewn up. They cannot be faulted for their attitude and service. On this alone I would heartily recommend them to anyone.The 120SP is going into a TopFlight Corsair. Have just completed runin of the second motor without problem although when cold the motor feels very tight, but when hot seems to run fine although still a little eratic, which is what you would expect for a still tight motor. Quote Link to comment Share on other sites More sharing options...
Danny Fenton Posted March 25, 2007 Share Posted March 25, 2007 I have yet to meet someone that has fitted the SP in an enclosed cowling. I am contemplating whether one of these (90 size SP) would be suitable for a BT Hurricane. Brian Taylor originally used a Laser 75. Keep us updated on how the 120 performs Michael, I for one would be very interested. What's the span of the Corsair by the way? Quote Link to comment Share on other sites More sharing options...
Michael Boland Posted March 26, 2007 Author Share Posted March 26, 2007 The Corsair is a 63", Robart retracts, JR 77S reciever with a mixture of JR servo's for control.Currently putting the paint on the fuse and ready to prime the wing now the flaps are in and operational.The 120Sp fits entirely inside the cowl, muffler included.The next step will be the baffles required to get sufficient air flow for cooling. Quote Link to comment Share on other sites More sharing options...
Michael Boland Posted July 6, 2007 Author Share Posted July 6, 2007 Just an update on the 120SP cowl mounted, after a dozen flights the motor is getting stronger each flight.No cooling problems encountered, but I was sure to set up the baffles in the cowl as described by RCV.The only problems I have encountered are vibration problems, cowl bolts and engine mount bolts rattling loose, and the muffler end plug coming out of the muffler.Locktite on all bolts and using an OS muffler (welded in end plug) has solved these minor problems.These motors have ample power and their profile makes them a snap to cowl mount.Currrently fitting 2 of them to a P-61 Black Widow. Quote Link to comment Share on other sites More sharing options...
Michael Boland Posted July 7, 2007 Author Share Posted July 7, 2007 The 120SP is very "barky" in its exhaust sound. The detonations are much more audible. This is probably why the muffler gets such a hard time.It is louder than most other 4 strokes.The exhaust temp is also much higher than other 4 strokes I have noticed.The next project is well under way and will be using 2 x 120SP's.The sound of 2 running in sync should be ausome. Quote Link to comment Share on other sites More sharing options...
The real Ron Truth Posted July 8, 2007 Share Posted July 8, 2007 Michael, Ive got the sp 60 in a flair pup and an rcv 90 sp in a large eindecker. Both run faultlessly although the 60 did suffer the same problem as yours when new. The problem you described was evident in early batches and was the result of square cut teeth as opposed to bevelled teeth. They simply smashed themselves to bits!!RCV has the best customer service to date and really looks after their customers.Ive found the engines become less noisy over time. My 90 has done probably 4 hours running and has becomes noticeably quieter. The whining of the gears is still unique and certainly gets heads turning!!My 90 happily pulls 14 llbs of model round without fuss and has never missed a beat. Quote Link to comment Share on other sites More sharing options...
Michael Boland Posted July 21, 2007 Author Share Posted July 21, 2007 Sadly I have experienced another failure of a 120 SP. This time in flight, strange sounds then silence. I was able to dead stick the Corsair onto the runway without damage.The engine has sheared off a good section of pinion gear.Hardened metal through the rest of the motor has not done it any favours.RCV state this has never happened before but I am finding other accounts on RCUniverse of 120SPs doing this exact same thing.I am really coming to the conclusion that these motors are nice in concept, and may work in the smaller sizes, but the 120 has very real problems.I do not think I will be trusting the twin to two of these. Quote Link to comment Share on other sites More sharing options...
Michael Boland Posted July 22, 2007 Author Share Posted July 22, 2007 I have also lost muffler ends on this motor. Solved it by using an OS muffler which has the end plug welded in place.At the time of failure I was testing a new caby sent over from RCV to try and solve the rough running problems at mid to low rpm.Fuels used consist of 10% to 15% Coolpower synthetic oil, 5% Castor, 5% Nitro.In our conditions 20% oil is recommended although RCV recommend only 15% oil in total.The engine was running fine, strong and no adverse noises. It started to run a bit rough at the top end so I backed off the throttle to half and all was fine for 5 minutes.When I opened the throttle again the engine started to miss and cough at the top end so I backed off to half throttle again, called landing and started the approach.That is when the rather not nice noises started, and a second or so later the engine cut. Luckily I had not lowered flaps and was on the final leg.It is my policy to keep new engines on the rich side. Idle was sloberingly rich, and the top end is about 600 rpm from peak. Fuel is pressure fed from the muffler.The 58CD I have runs very well. Quote Link to comment Share on other sites More sharing options...
Michael Boland Posted July 22, 2007 Author Share Posted July 22, 2007 Good question.At this stage they have just asked for the engine back and have not yet stated their intentions to replace it.I wonder if they will be backing away from Aeromodelling now they have that US Defence contract? Quote Link to comment Share on other sites More sharing options...
Adam Chambers 2 Posted July 23, 2007 Share Posted July 23, 2007 I have found with my 90 sp that you have to trade off top end power with mid/low range smoothness. As I tend to fly a lot at 1/2 throttle, I run a tad leaner than I would do if tuning for full power. Ive tried to get a nice clean running full power setting to find that 1/2 throttle involves a lot of burbling and popping. I can only suggest you run a lower oil content fuel, such as model technics contest 10 which is 18% synthetic oil and 10% nitro. I use this and it was a huge improvement over the caster oil duraglo I used initially. Duraglo used to cause no end of burbling and a poor full power setting. Try that. Ive seen engines transformed by a change in fuel. Quote Link to comment Share on other sites More sharing options...
Adam Chambers 2 Posted July 23, 2007 Share Posted July 23, 2007 er not sure I follow you jetsome? Mid range smoothness in my experience requires a leaner mix than full power, only a few clicks but its the differnce between popping and smoooooth. Quote Link to comment Share on other sites More sharing options...
Michael Boland Posted July 23, 2007 Author Share Posted July 23, 2007 Thanks for your suggestions.I have taken one of the 120's from the Black Widow and put it in the Corsair. Until I find what is going on with these motors I am not going to trust them in a large twin.As I mix my own fuel I will be trying your suggestion of no castor and will report on any differences.The other variable in my equation has been the use of CoolPower MultiViscosity Synthetic Oil (the purple stuff) instead of the ordinary blue. Next batch of fuel will be CoolPower blue and no castor.I have avoided leaning the motors right out as you suggest, and yes I had noticed better mid range with a leaner top end, but I have always been very careful about running new motors lean, and prefer the drop in performance for the safety of the motor until I am comfortable with it. Quote Link to comment Share on other sites More sharing options...
Allan Jordan Posted July 23, 2007 Share Posted July 23, 2007 Hi Michael, Get rid of that castor oil ASAP.I would never use it in any four stroke engine. This might just be the answer to your problem. Allan J..TTFN Quote Link to comment Share on other sites More sharing options...
The real Ron Truth Posted July 23, 2007 Share Posted July 23, 2007 Im not suggesting you run it so lean its not creating any lube!The rcv only has one main needle so you cant fine tune low,mid and high end settings. I found that once you got full rpm at full throttle, backed it off 4-5 notches, you had optimun rpm ( not max, optimum) . If you them brought the throttle to half, she burbles and pops like crazy. So its 2-3 clicks to lean her a bit and the mid range is now sweet and smooth. Such small variations are going to be OK. I would suggest you run any engine so lean as to risk damage. When I land my rcv, the engine , cowl and model are plastered in oil!!! Quote Link to comment Share on other sites More sharing options...
The real Ron Truth Posted July 23, 2007 Share Posted July 23, 2007 Jetsome 1 Me 0. Quote Link to comment Share on other sites More sharing options...
Michael Boland Posted July 23, 2007 Author Share Posted July 23, 2007 RCV are sending me 2 new main needles for the remaining 2 motors.Also a new muffler.From what I am seeing their good motors are being let down by less than adequate carby's and just plain crap mufflers. Quote Link to comment Share on other sites More sharing options...
Michael Boland Posted July 26, 2007 Author Share Posted July 26, 2007 Just a few pics of the Corssair for your edification Quote Link to comment Share on other sites More sharing options...
Adam Chambers 2 Posted July 26, 2007 Share Posted July 26, 2007 ooh ive just dribbled on my keyboard....... Quote Link to comment Share on other sites More sharing options...
Michael Boland Posted July 26, 2007 Author Share Posted July 26, 2007 Thanks, it's always nice to get compliments.Now if I caould just that ^&&&%^( motor running it will be sweet.This is what I am now reconsidering.and this is why Quote Link to comment Share on other sites More sharing options...
Adam Chambers 2 Posted July 26, 2007 Share Posted July 26, 2007 holy crap thats nothing to do with fuel!!!Even I can see there is something very very wrong with the construction of that rcv. Come on rcv, you know this is not right. Quote Link to comment Share on other sites More sharing options...
Jon Black Posted July 27, 2007 Share Posted July 27, 2007 go for a saito 125, 2/3 the weight, cheaper and more powerful Quote Link to comment Share on other sites More sharing options...
Michael Boland Posted July 28, 2007 Author Share Posted July 28, 2007 Saito is the way I am leaning, but they are proving hard to get here in Australia. Quote Link to comment Share on other sites More sharing options...
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