Author Topic: Steve Moon Where are You (Read 7260 times)

proparc · « **on:** July 28, 2009, 11:37:21 AM »

For quite some time, I have been looking at,(and admiring)the work of Steve Moon and his OS Max 4 stroke program. Prior to the release of Saito's 72, I had been looking at and running various Max 4 strokes, in particular the 52. I was not able to make it happen. Steve obviously did. Steve has moved on the the new OS max,(Bluehead) and is again, seeing success. I would like to see him weigh in here and I am sure we would all appreciate and be fascinated with his comments on this underutilized power plant.

SteveMoon · « **Reply #1 on:** August 09, 2009, 11:01:28 AM »

Hi Milton: Where am I? Lately, I've been in Nagoya, Manila, Tokyo, Amsterdam
and some other places.

Anyway, yes I have moved onto the OS 56 FS-A, but I seem to be having some
teething problems. There is no doubt the motor has gobs of power, but I seem
to be getting some detonation during the run. And, it does this no matter
what % nitro I use. This causes the motor to lose power as the flight progresses.

I never had this problem with the OS 52, so I originally though there may be a
mechanical problem with the motor. I sent it back to Great Pains and they said
there was nothing wrong with it. Now, the plane I have been using it in is overwieght
by about 10 oz., so today I am going to take the 56 out of the Furias 96 and install
it in the trusty old Saturn and see what happens.

I ahve been flying Saturns with the OS 52 for almost 5 years now, and never really
had any problems. The 52 is incredibly consistent and has good power. At the
2007 Nats Stan Powell was blown away on the second day of qualifying when he
judged my afternoon flight on circle one with a strong wind coming right up the
hill. The little 52 just powered right on through and I put in a good enough flight
to qualify for Open Top 20.

I'm going to keep fiddling with the 56 and see what happens. I'll let you know.

Steve

Martin Quartim · « **Reply #2 on:** August 09, 2009, 04:27:25 PM »

Hi Steve,

The OS 70 Ultimate especially the older ones has the same problem and we fix it using one extra head gasket.

Or perhaps you can try a smaller prop.

Martin

Willis Swindell · « **Reply #3 on:** August 09, 2009, 05:08:38 PM »

I had a similar problem with the Surpass 40. Plus I could not keep the engine from kicking the prop off, I installed a head gasket and cured the problem. I still make sure I keep the prop tight.
Willis

Greg Frail · « **Reply #4 on:** September 28, 2009, 05:33:02 AM »

Hi Guys,
I have read your comments here with great interest. I built a Brian Eather design Firecracker for the Saito 56 a couple of years ago. No matter what I tried I could not fix a lack of line tension up top. The model ended up a little heavy but not excessive as 60.5 oz. When the OS56A came out I purchased one and initially the engine seemed to perform very well. However the engine is currently gaining about half a second a lap over the pattern and again I have not been able to fix it. I have tried several tanks, castor and synthetic fuel and different props, I am currently running the engine on pressure. I have found that the OS has more power than the Saito. The OS also uses less fuel, less nitro and runs on a smaller venture. I am not sure what detonation sounds like but my engine sounds a little rattly, although there is nothing loose in it or the model. I have been thinking about adding head shims as this is part of a fix for the FP40’s when they run away, what do you think? Have any of you experienced this sort of problem with the lap time gradually decreasing as the flight progresses. When I was using the Saito, the lap times were dead constant from start to finish. Any thoughts will be appreciated.
Greg Frail

Martin Quartim · « **Reply #5 on:** October 25, 2009, 09:13:29 PM »

Greg,

I have no experience with either engine. But I did have some speed up problems, it was with my Saito 72 but only when using 10% nitro and in a hot day. If I used 15 or 20 it did not speed up that much. Don't know if that helps any.

One of my friend just got a OS 56 alpha, he was happy until a hot and humid day arrived down here. We will work on his engine setup this week, if any one has some input it would be great, our NATS will be this weekend.

One of the things we plan to try is messing with the plug washer height, making the distance from the plug to the piston further to see if we can some how change the ignition time.

Martin

Bradley Walker · « **Reply #6 on:** November 23, 2009, 07:32:40 AM »

I am convinced these engines need head gaskets. They are too compressed, which makes them very peaky.

Steve Fitton · « **Reply #7 on:** November 23, 2009, 08:35:51 AM »

I thought Steve tried head shims at Muncie to no avail? He seemed to be trying everything else-I've never seen somebody take an engine completely apart under field conditions as fast as Steve

Martin Quartim · « **Reply #8 on:** November 23, 2009, 08:27:50 PM »

I have exchange emails with Steve Moon and he did not mention adding head gaskets trying to fix it.

We use two washers under the glow plut and the pre igniton problem got better but not resolved. We are waiting to get a head gasket to try it on.

Some other OS 56FSa has been working stock great here. I think the difference could be the ring gap. One of the engines that has been running great does not have as much as compression as the one that is creating problems, we don't know for sure but I suspect the ring gap could be part of the trick.

Martin

Greg Frail · « **Reply #9 on:** November 26, 2009, 05:04:21 AM »

Hi Martin,
Thanks for your thoughts. For the OS56a I made and installed 3 head gaskets a little over 3 thou thick each, I also put the original head gasket back in. So I have added 10 thou all up or there abouts, the compression is lower and feels more like the saito now. This seems to have settled the engine run down lap times are close enough to the same at the start of the flight to the end of the flight. One thing I have found is that the OS56 has to run a little leaner, if it is set rich it will lean and get quicker towards the end of the flight, don't know why that's just how I have found it. By the way, I am using 20% coolpower and 10% nitro for fuel, a metal clunk tank at the moment the same as hoffo makes and a 14x5.5 CF Brian Eather prop. The prop is cut to about 13.5 and has had some undercamber taken off at the tips. The head gaskets were made from the alloy seal in the top of a coffee or milo tin.
Thanks again
Greg

Martin Quartim · « **Reply #10 on:** November 26, 2009, 07:47:32 AM »

Quote from: Greg Frail on November 26, 2009, 05:04:21 AM

Hi Martin,
Thanks for your thoughts. For the OS56a I made and installed 3 head gaskets a little over 3 thou thick each, I also put the original head gasket back in. So I have added 10 thou all up or there abouts, the compression is lower and feels more like the saito now. This seems to have settled the engine run down lap times are close enough to the same at the start of the flight to the end of the flight. One thing I have found is that the OS56 has to run a little leaner, if it is set rich it will lean and get quicker towards the end of the flight, don't know why that's just how I have found it. By the way, I am using 20% coolpower and 10% nitro for fuel, a metal clunk tank at the moment the same as hoffo makes and a 14x5.5 CF Brian Eather prop. The prop is cut to about 13.5 and has had some undercamber taken off at the tips. The head gaskets were made from the alloy seal in the top of a coffee or milo tin.
Thanks again
Greg

I am glad you got your engine running well. Also I suggest you to try an JXF electric 13x6 or 14x6 These props are very light and very efficient. I am not sure about the OS 56FS but my OS 70 Ultimate prefers a light prop. The JXF electric props are actually stronger then Top Flite power point for glow, so I am using them without a doubt.

Martin

Bob Reeves · « **Reply #11 on:** November 26, 2009, 08:33:25 AM »

Quote from: Greg Frail on November 26, 2009, 05:04:21 AM

Hi Martin,
Thanks for your thoughts. For the OS56a I made and installed 3 head gaskets a little over 3 thou thick each, I also put the original head gasket back in. So I have added 10 thou all up or there abouts, the compression is lower and feels more like the saito now. This seems to have settled the engine run down lap times are close enough to the same at the start of the flight to the end of the flight. One thing I have found is that the OS56 has to run a little leaner, if it is set rich it will lean and get quicker towards the end of the flight, don't know why that's just how I have found it. By the way, I am using 20% coolpower and 10% nitro for fuel, a metal clunk tank at the moment the same as hoffo makes and a 14x5.5 CF Brian Eather prop. The prop is cut to about 13.5 and has had some undercamber taken off at the tips. The head gaskets were made from the alloy seal in the top of a coffee or milo tin.
Thanks again
Greg

The greater speed up running rich is the same thing I see on my Saitos. I run conventional venting on muffler pressure and always felt it was the result of not being a uniflow vent. Been afraid to try a uniflow clunk tank as the runs I'm getting are almost too good to mess with. I normally see about a 0.2 second increase in speed from a full tank till just before it quits but I like it as it gives me just a little more oomph for the verticals and clover. If I set it too rich it can easily go to 0.4 or 0.5 seconds.

Willis Swindell · « **Reply #12 on:** November 26, 2009, 05:23:59 PM »

I run uniflow in all my 4S and most have no problems BUT at first they would go richer once the uniflow got out of the fuel. I use plastic tanks with two clunks. I finally ran the uniflow all the way to the rear of the tank that cured that problem except on my Phoebus it would go rich after the horizontal eight's. I tried every thing but finally just un plugged the over flow and it works fine
Willis

SteveMoon · « **Reply #13 on:** December 15, 2009, 07:49:28 AM »

UPDATE: This past Sunday I flew my Furias 96 with the OS 56 FS-A
with a head shim added. The head shim from the OS 61 SF is a direct
fit for the 56 FS. After adding the shim, I reset the valve gaps and
headed out to the field.

This was a definite improvement. The detonation (and general all around
loud knocking) was gone. This motor has gobs of power and pulls like
a truck. The F96 is grossly overwieght and I am next going to try the 56 FS
in my trusty old Saturn. There was a little (just a little) bit of sag during
the second half of the square eight and the second veritcal eight. I
am pretty confident that the 12 oz. lighter Saturn won't have this problem.

Later, Steve

Martin Quartim · « **Reply #14 on:** December 16, 2009, 04:22:49 AM »

Good to hear that Steve.

We are still waiting the darn gaskets to arrive here.

How's the fuel consumption and what size prop, venturi and spray bar are you using?

Cheers,

Martin

SteveMoon · « **Reply #15 on:** December 16, 2009, 07:15:15 AM »

I'm using only about 3 oz. of fuel per flight, which is less than
what I was using with the OS 52. It took about 3.625 oz. to
finish the pattern. Seems like it should be a bit more to me.
I'm using a 'spigot' OS NVA. It doesn't actually go all the way
through the venturi. If I remember correctly the venturi is a
.225, but I'd have to measure to make sure.

Steve

Martin Quartim · « **Reply #16 on:** February 09, 2010, 09:36:44 PM »

Hi Steve,

The gaskets arrived and we end up installing 3 in it. The engine improved a lot and now it is running well, but still there is a bit or pre ignition. For some reason we are narrowminded to use OS F plug, but this coming weekend we will try an Enya 4 Medium Hot plug and see if that helps. Perhaps we can use less gasket with a colder plug.

Cheers,

Martin

SteveMoon · « **Reply #17 on:** March 28, 2010, 04:50:41 PM »

Martin: I ordered some more head shims for my OS 56 FS-A and added
two more. Friday I put in a couple of flights with now 3 head shims in
the motor, and it was much improved. It ran very smoothly and very
consistent and still with plenty of power. The fuel consumption has also
gone up, requiring 3.5 oz of fuel for the full pattern. A definite improvement.

Steve

Willis Swindell · « **Reply #18 on:** March 29, 2010, 07:04:31 AM »

Steve
Is the OS 56 one of the engines that reroute the engine lubrication oil back into the combustion chamber? if so maybe that is adding to the compression.
Willis

proparc · « **Reply #19 on:** March 29, 2010, 08:20:32 PM »

Sounds like that OS is packing some serious compression.

Author Topic: Steve Moon Where are You (Read 7260 times)

Willis Swindell

Willis Swindell

Willis Swindell