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Breaking in an RCV90-SP - 6/16/2003 7:30:52 PM   
Juice



Posts: 865
Joined: 2/12/2002
From: Richmond Hill, ON, CANADA
Status: offline 		I fired up my RCV90-SP for the first time over the weekend.

I'm using Wildcat fuel... 10% nitro, 18% total oil (80:20 synthetic/castor mix). I put on a 16x14 2 blade prop as recommended by the people at BlackFly Aero. I'm going to use Otto's break-in procedure, which is four 15 minute runs at 1500 RPM, then four 15 minute runs at 2000, then four 15 minute runs at 2500, etc, etc, until max RPM is reached.

I set the high-end needle 2 turns open at the start of the first run. I started the engine and had it running between 2000 - 2500 RPM for the first 5 minutes. After that I was able to get it down to between 1500 - 2000 RPM for the next 10 minutes. Throughout the run, I was continually setting the high-end needle richer and richer because I didn't notice any "slobery wetness". I kept the glow igniter on and the throttle setting was constant throughout the whole run, but the engine kept speeding up and slowing down in 500 RPM swings. Is this normal?

I set the high-end needle 4 turns open at the start of the second run. The engine was running a much more consistently between 1450 and 1500 RPM.

Questions to Otto, or anyone, about the break-in procedure... When do I start to lean out the high-end needle? Do I keep it very rich for the whole duration of the break-in period (which is quite long)? Is it correct NOT to rev the engine at high RPMS during the break in procedure? In other conventional engines, you run the engine over it's entire RPM range during break in, right? But not these RCV?

Thanks,
Juice

(Later tonight, I'll post video of the first run on my web site)
       Post #: 1

Breaking in an RCV90-SP - 6/17/2003 10:11:26 AM   
Otto Kudrna



Posts: 373
Joined: 2/19/2002
From: Burr Ridge, IL, USA
Status: offline 		Hello Juice

Questions to Otto, or anyone, about the break-in procedure... When do I start to lean out the high-end needle? Do I keep it very rich for the whole duration of the break-in period (which is quite long)? Is it correct NOT to rev the engine at high RPMS during the break in procedure? In other conventional engines, you run the engine over it's entire RPM range during break in, right? But not these RCV?

What I do, is after the first 15 minuets I bring up the throttle just long enough, to set my needle about 3-4 clicks rich. Than I go to as slow as I can get the engine to run, and set my lo end needle. This is usually on the rich side. The RCV will not idle with the lo needle too lean. I like to get my idle with a rich burble instead of the barrel opening. Once you have the needles set than brake in the engine at these settings. There is no reason to brake in the engine with a rich setting. You should not and most likely will not ever get a lot of smoke threw the exhaust. Most of the oil should come threw the crank vent. The two indicators of a broken in engine are. the compression is held once the engine is cold, and the residue from the crank is no longer black. I have found that these engines do not get their full power until about 10-12 hours of running. This is due to the fact that the engine is equipped with a steel ring and not iron. The ring is less brittle and than fore takes longer to seat. I would not run the premium plus with 18% oil but rather the premium with only 16% oil. You will find that the engine will be much easier to set. These engines are designed to run with 15% oil, running much more than that will not give any benefits and may actually cause undue detonation. You will find that braking in the engine slowly will give quite a bit more power at the end. I would also go to a master airscrew 18x10 wood prop for the procedure. It gives a better load and cools the engine better. I have within the last couple of weeks been working on a new brake in procedure that seems to work even a little better. after the first three 15 minute cycles and cool downs. I fill up the tank to the top (50oz) and start the engine. lock it at 2800 revs and let it run the tank dry. I do this for 1-2 Gallons of fuel or until the engine holds compression, which ever comes first. This seams to put very little stress on the engine and has given me terrific results. For example; I have been running in a 58CD for the last two days. I have put 72oz of fuel threw it at 5000 rpm, 24 oz at a time. I have done this with two engines. I am getting 10300 revs with a M/A 12x6 plastic prop. Where as using my former procedure I have only been able to get 9900rpm. The low speed keeps the engine cool while getting the valve seal area hot enough for the varnish seal to build up in the iron sleeve. I have just done this to my 90, which I thought was broke in (after 60 hours) and managed to pull another 300 revs out of her afterwords.

Otto Kudrna, RCV Tech Support

(in reply to Juice)
       Post #: 2

Breaking in an RCV90-SP - 6/17/2003 10:50:14 AM   
Juice



Posts: 865
Joined: 2/12/2002
From: Richmond Hill, ON, CANADA
Status: offline 		Thanks Otto...

The engine now has 1 hour at 1500 RPM and 15 minutes at 2000 RPM. Every minute of which was very very very extremely rich. Next time I'll set the high-end like you said. I always screw up when I play around with the low-end needle, so I'll probably leave that for later.

During the first couple runs, the RPMS would vary +/- 250 RPM. Now it is varying +/- 50 RPM. I assume this will get better as I continue to break it in? Is this normal?

As promised, here's the link to the video of the very first 30 second run:
[URL=http://members.rogers.com/jsrc3/RCV90_BreakIn.html]Breaking in the RCV90[/URL]

Juice

< Message edited by Juice -- Jun 20 2003 9:45PM >

(in reply to Juice)
       Post #: 3

Breaking in an RCV90-SP - 6/17/2003 2:59:10 PM   
Otto Kudrna



Posts: 373
Joined: 2/19/2002
From: Burr Ridge, IL, USA
Status: offline 		Hi Joshua
I went on your web sight and took a look at your video of the first RCV run. You have a very good tight engine. I would strongly recommend that you brake this one in very slowly. Just let this one run at no more than 2500 revs for long periods of time. Allow the bearings to seat and the valve area to build up the varnish seal. Also get rid of that gray piece of plastic you are spinning on the front and put on a good Master Airscrew 18x10 for brake in. I will mail you a video tape of my RCV 90 via post. It shows it turning a M/A 20x13 (cut down to 19" and also a Zinger 15x12 three blade (measured at 14" pitch actual). It turns the three blader at about 5500 rpm. That would really haul your Corsair around nice. I did not notice if you listed your mailing address on your web sight. If not mail it to me directly, and I will send out the tape.

Otto Kudrna
[email]condorusmc1@aol.com[/email]

(in reply to Juice)
       Post #: 4

Breaking in an RCV90-SP - 6/18/2003 8:38:33 AM   
Juice



Posts: 865
Joined: 2/12/2002
From: Richmond Hill, ON, CANADA
Status: offline 		I ran the engine another 2 x 15 minutes today at 2000 RPM still very rich (2 turns open). Total run time so far is 1 h 45 m.

[QUOTE]Originally posted by Otto Kudrna
Just let this one run at no more than 2500 revs for long periods of time.[/QUOTE]

I don't know how to interpret this comment. Do you mean never exceed 2500 RPM, not even to tune it 4-5 clicks rich, and run it for long periods of time like this? Or do you mean it's okay to exceed 2500 RPM, to tune it 4-5 clicks rich, but not for long periods of time?

I went with the second definition when I tried to run the engine a third time tonight. I got the engine really hot at 4600 RPM and then richened it by 5 clicks. There was excessive vibration at full throttle and I noticed that one of the clamps that was holding stand to the table came loose, so I stopped the engine. While re-tightening the clamp, I noticed that the 4 mounting bolts on the engine had also come loose. Then I noticed the muffler had come loose too. I decided to call it a night and packed up. Total run time on the third run was 1 minute to tune it 5 clicks rich.

My questions for today:
1) Should I not have run the engine at full throttle yet?
2) Is 4600 RPM normal at full throttle at this stage of the break in procedure?
3) Is excessive vibration normal at full throttle at this stage of the break in procedure?
4) How am I doing? Am I on the right track for proper break in?

I'm still using the 16x14 2 blade APC and the 10% nitro with 18% oil Wildcat fuel. I'm stuck with them for now.

Thanks for all your help,
Juice

(in reply to Juice)
       Post #: 5

Breaking in an RCV90-SP - 6/20/2003 12:27:40 AM   
Juice



Posts: 865
Joined: 2/12/2002
From: Richmond Hill, ON, CANADA
Status: offline 		Just another boring update:

I put in another 30 minutes last night. 15 minutes at 2000 RPM and 15 minutes at 2500 RPM. Total run time so far is 2 h 15 m. It's running a lot steadier now at a given throttle setting, varying only +/- 20 RPM. I also re-adjusted the high end and got 5500 RPM (w/ the 16x14 APC) before I richened it down to 5000 RPM. Nothing vibrated loose this time, but it did blow off my baseball cap!

I haven't touched the low end setting yet, nor have I tried it's idle performance at this stage of break-in. I'm going to give it a try next time out.

Last night was training night and I had a larger than normal audience of instructors and students watching me fire it up. It was the first time for many of them seeing and hearing an RCV engine. It does attract a lot of attention.

Juice

< Message edited by Juice -- Jun 19 2003 7:33PM >

(in reply to Juice)
       Post #: 6

Breaking in an RCV90-SP - 6/20/2003 9:19:25 PM   
John Palica


 

Posts: 1217
Joined: 5/22/2003
From: Vernon, CT, USA
Status: offline 		The more I read about break in of the RCV the confusinger it gets. I'm not at the stage where break in of my 90 is a necessity yet, so I read with great interest, Otto's guidance on the subject. My plans were to run a Zinger 18-14 or a 20-12 with 10% nitro and 14% lube (7 and 7) using the 15 minute run and cool technique. Looks like the revised break in with the long run at 2800 after 3 15 minute run-cools is the way to go. Seems like it greatly simplifies the process and reduces the total time involved. Otto, please keep us posted on your findings with the new procedure
)

_____________________________

John

(in reply to Juice)
       Post #: 7

Breaking in an RCV90-SP - 6/24/2003 4:49:17 PM   
RCV Engines


 

Posts: 511
Joined: 4/11/2002
From: WimborneDorset, UNITED KINGDOM
Status: offline 		Hi John

I understand your comment that the more you read about the break-in of the engine the more confused you get.

If the RCV instructions or Condor Model instructions are followed - this is perfectly adequate for running in the engine. It is as simple as that.

I think that some of the posts here have requested for even more information on running in and so Otto has provided his own running in process to the letter. Obviously this can be followed if required, but I would like to highlight that all the important information is included in the RCV user manual.

I hope this simplifies the situation.
Best regards
Laurenne


_____________________________

Technical Support
RCV Engines - UK

(in reply to Juice)
       Post #: 8

Breaking in an RCV90-SP - 6/25/2003 1:26:53 AM   
Juice



Posts: 865
Joined: 2/12/2002
From: Richmond Hill, ON, CANADA
Status: offline 		Just an update...

I've used one full gallon of fuel already which provided me with 5 hours of running time. I've done 4 x 15 minutes at 1500, 2000, 2500, 3000 and 3500 RPM, all with a 16x14 APC prop. I need to get an 18x12 APC to do some final adjustments to try to get 1200-1500 RPM at idle and 5100-5500 RPM at full-throttle.

With the 16x14 APC prop, I had trouble adjusting the high end because of excessive vibration when the prop hits 4500 RPM. It was vibrating so much that the mounting bolts came loose again and I had to shut down before I could adjust the needle. I think I know the reason for the vibration... an unbalanced prop. I bought a prop balancer and confirmed that one prop tip is definitley heavier than the other. After doing a search on here on RCU, I read that large props MUST be balanced, whereas smaller props can do without (but it's still better to balance even small props). Anyway, I'll try it again with balanced prop and see how it goes.

JP... I'm asking so many questions because I'm still relatively inexperienced when it comes to engines. My inexperience is showing in this thread. I'd rather ask questions and look dumb to save my $500 (Canadian) invested in this engine. If you ask 10 different people you'll get 10 different break-in procedures, and each is correct in their own way. Whatever break-in procedure you choose, just stick to it. It's a great engine, you'll love it.

Juice

(in reply to Juice)
       Post #: 9

Breaking in an RCV90-SP - 6/30/2003 6:46:15 PM   
John Palica


 

Posts: 1217
Joined: 5/22/2003
From: Vernon, CT, USA
Status: offline 		Juice:
Thanks for the reassurance. $309 US is also a lot of $$$$$$$$$ and I also want to be sure I don't mess up the engine. I'm anxious to get into the break-in process. I've made a mount plate to fit to a friends test stand and have the props. I purchased a Zinger 18X8-14 and a 20X12. Got a Master Air Screw 16X10 3 blade for flying my P6E. Your comment about vibration resulting from prop unbalance is valuable info. I will be sure my props are balanced accurately. I have had good luck with Red Max blending my fuels so I will probably go to them for some 10% with 7 and 7 oil. Need some 60% for my race boats and regular 10% for my 2 strokes anyway. That will consume another $100+.

_____________________________

John

(in reply to Juice)
       Post #: 10

Breaking in an RCV90-SP - 8/24/2003 6:12:11 AM   
Juice



Posts: 865
Joined: 2/12/2002
From: Richmond Hill, ON, CANADA
Status: offline 		The engine has been sitting doing nothing for the past two months. I've searched every hobby shop in the city for the proper fuel, but nobody carries RCV-friendly fuels. Wildcat fuels are the closest match.

I bought another gallon of Wildcat 10% nitro 18% oil (syn/castor blend). I am using the same APC 16x14 prop. This time it is properly balanced and all vibrations at high RPM are gone.

I had problems idling today. When I set the throttle so that the carburetor opening is just a tiny crack, the idle RPM is about 2150 RPM. Fast transitions from this idle to full throttle is smooth. Fast transition from full or mid throttle to idle causes the engine to die. If I transition slowly to idle, then the engine stays alive. When I say slowly, I mean a 2 or 3 seconds on each click of the throttle stick all the way down to idle. It also will not start on idle. I need to set the throttle at about 1/4 for it to start.

Thinking about it afterwards, I think the low needle is too lean. Am I right in thinking this way? What idle RPM should I expect with an APC 16x14?

Thanks,
Juice

(in reply to Juice)
       Post #: 11

fuel - 8/24/2003 6:18:25 PM   
grinder-RCU



Posts: 587
Joined: 2/18/2003
From: London, ON, CANADA
Status: offline 		Hey Juice check out this guy he has lots of fuel at his store. I picked upped some XP Blend 15% nitro 18% oil 100% syn. it was the closest i could find to match RCV reconmended fuel.

http://www.skycrafthobbies.com

Joe.

(in reply to Juice)
       Post #: 12

Breaking in an RCV90-SP - 8/24/2003 8:26:29 PM   
Otto Kudrna



Posts: 373
Joined: 2/19/2002
From: Burr Ridge, IL, USA
Status: offline 		Hello Gents
In the RCV instruction sheet it states clearly the blend of; 10% Nitro 15% oil. Oil should be a blend not straight. if there is no castor in the oil the engine will never develop full power because the valve will never seal completely. The valve is a Steal on Iron combination and requires castor. If the oil content is increased past 15-16%, the nitro content should under any condition not be more than 10%. If the oil content is between 14-15% you may go up in nitro slightly if you are in higher altitudes. If you have any questions on proper setup or running you may call me at (630)321-0580 I have over 600 hours of running time on RCV engines, and know a few tricks.

Otto

< Message edited by Otto Kudrna -- Aug 25 2003 2:19PM >

(in reply to Juice)
       Post #: 13

Field report - 8/28/2003 11:00:45 AM   
Juice



Posts: 865
Joined: 2/12/2002
From: Richmond Hill, ON, CANADA
Status: offline 		I bought and balanced an APC 18x12. Now I know what idle RPM to aim for (1200 - 1500 RPM). I also bought a little one ounce fuel tank to catch the crankcase residue. This cleans up the whole break-in process because there is much more crankcase residue than exhaust residue. After using it for the first time, I strongly recommend it.

In my last post, I suspected that the idle needle was too lean. I found out today that it was very lean... I had to richen it by about one turn. With this adjustment and the larger prop, the engine is running it's best yet. I got it to idle at about 1300 RPM. A few more sessions will bring it down more. The high end peaked at about 5500 RPM.

I'm still having the problem where a quick transition from high or mid range to idle causes the engine to die. I need to