Need some info on the 503/Warp combination.

Resasi

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Just finished the full Rotax run in procedure on our new 503.

I had been advised by the guy at the Warp factory that between 9-11 degrees should give us around 310 lbs of thrust on a DCDI 503. ( was he blowing smoke???

With the prop set at 8 degrees we were unable to get over 5900rpm max throttle and this gave us around 230lbs of thrust which didn't seem anywhere near the figures I was expecting.

I have spoken to Lockwood this morning. Their 2 stroke rep confirmed that the RPM was too low and that a lower/finer pitch should bring them up, and that there should have been no harm done to the engine

I am now going to reset/ de-pitch the prop to achieve 6500RPM and see what thrust I get.

I have been told that this procedure can be fairly critical but was wondering if any of you have had either experience with this combination or have some advice or comments on best way to get the best available thrust.
 
Leigh, don't worry what the setting is just pitch it for correct static rpm and she'll be fine. You'll be amazed how much more you'll get from the last few hundred revs.
 
Leigh,

8 degrees relative to what? For example... You are measuring 8 deg. on the down going blade when horizontal ( prop installed on the gyro). IF the engine / Gyro is 3 deg. NOSE down then the REAL pitch is 8+3 = 11 deg.

You mast make sure that the prop is at 0 degrees or measure the angle of the prop hub, find if it is nose up or down and adjust 8 deg from there.

Of course this so obvious but i thought i would mention it... you never know. De pitch the prop until you get 6600- 6700 on the ground and the trust will increase.

P.S.

Your prerotator is on its way.
 
8 degrees relative to what? For example... You are measuring 8 deg. on the down going blade when horizontal ( prop installed on the gyro). IF the engine / Gyro is 3 deg. NOSE down then the REAL pitch is 8+3 = 11 deg.

You mast make sure that the prop is at 0 degrees or measure the angle of the prop hub, find if it is nose up or down and adjust 8 deg from there.

That's the question that came to my mind when first mentioned in the other thread. I have seen folks try to set pitch with the machine rocked back on its tail wheel on an upward inclined driveway!
You must do whatever necessary to level the engine, or more specificly, assure the prop hub is "zero" as refference plane.
 
Thanks for the feedback guys. Yes I was following all the instructions to the letter re pitching the prop.

I made sure that the keel and engine mount were horizontal, that I had the protactor in the correct position.

I had begun with nine or so I thought. In fact just over 8 on two and the third just under 8 by a fraction. This was producing the 5800 approx and the 220lbs.

Having spoken to Lockwood I began by de-pitching to 7 degrees on all blades and in addition the when measuring the degrees of pitch making sure that the leading edge of the prop was also completely horizontal with a second level. This did make a difference.

The next run at 7 gave a reassuring increase in both RPM and thrust.
I achieved 6150RPM and 295lbs.

The next de-pitch was 6 degrees and BINGO 6550/6490 (it does wander a bit) and the thrust was now up to 321lbs.

I have to admit to being highly relieved and delighted. The engine was running very smoothly and it all sounded great.

Nicolas that is great news on the prerotator, thank you. I am really looking forward to putting it on the head and then doing the hang.

I will have to admit that 6500 static is going to be pretty close to 6800 in the air and as I had pretty much nailed what the Warp factory had given as the thrust figure for the 62'' thre bladed prop on a 503 DCDI I wasn't going to do any more messing around with it.

Appreciate the comments thank you gentlemen. And yes Brian very surprised at what 1 degree does. I may try to fix our IVO up, the pitch changing on that is so much easier.
 
So you ran the break in procedure with the max rpms limited by the prop at less than 6000 rpms? If so then you didn't properly break in the engine.
 
Ron I was very worried that the whole run was invalid and might effect my warranty, a question I specifically rang Lockwood to ask

According to the 2 stroke technical rep at Lockwood it was not a problem as long as I had been able to achieve the top RPM figure specifically stated for the five minute run, which I did.

As long as the max RPM's at the full throttle periods had not been over 6800 RPM it was not a problem and the full run in procedure was valid and acceptable to them.

That's the information from them.
 
They might have been okay with it, but personally I would not like it if it were mine. You basically lugged or overloaded the engine through the entire procedure. Did it hurt anything, I don't know. But lugging it like that it may not have gotten the right temps to do a proper break in.

I always take a new engine and let it run at idle for a minute or two and then go to full power to check prop pitch, then back off and let it idle for another minute then shut down. Once I have prop pitch where I want it, I will then start the hour long break in cycle per the book.

In another thread you mentioned your prop and the gearbox. You will be okay so as long as you don't idle the engine too low. Put another way, at 3000 engine rpms the engine should be smooth, back off the throttle slowly to the lowest point you can go yet still have a smooth idle and set your carbs idle adjusters to that point. As long as you never idle the engine in the " Rough Zone " which is usually 2000 or less rpms you will be okay
 
Initial pitch setting to see what RPM you get. That might be good advice which unfortunately I had not been given nor read anywhere Ron, and believe I was looking. Might not however that also be non-procedure and damaging?

Temps got up to and remained in the normal range, I saw no specific target temps mentioned. According to the Airwolf manual it is the seating of rings and initial gradual and controlled wear of walls and pistons that is being achieved by this procedure. Was told by two people to skip the procedure it was not required which I chose to disregard

Yes it was lugging, no don't like the idea either. Console myself that at 8 degrees and around 5,900max it was not grossly over pitched. 2 degrees less bringing it up to target.

The guy at Warp should definitely forget his ideas of between 9 and 11, and luckily I did not get the 9 degrees I was initially aiming for but 8, 8, and 73/4. by not using the second level along the top of the prop blade to ensure that was also level.

Guess I will live with the run in that has been done.
 
I doubt you hurt anything.... Just would have been better in my opinion to have had the prop set up at the start of the run to allow 6500-6800 rpms. Its over and done with now so fly it and have some fun
 
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