mogman

Will there be a new ignition to fit the 400?

GaryM

My Feedback: (14)

Detlef Kunkel

Guys,
I dont know the final price yet, I only know that it will be (of course) more expensive than simpler ignitions for opposite twins or so, as the series is much smaller, but the technique is much more elaborate and complex. Its really high-end and state-of-the-art.

And I dont know if there will be a type for the 400 Moki.
The 400 is quite rare on the market, and thus demand for such a type is rather small. The work to match the ignition with one engine takes maybe some days, so I am not sure they will do that for one or two ignitions to be sold.

I guess it will take only a few days until you can get information about that from Goetz Vogelsang.

mogman

As this new ignition looks to be a "stand alone" unit, and assuming the hall/ignition sensors are all the same (physical) size?? ( I don't know this for sure), other than maybe the actual length of the plug wires, this should fit all the Mokis. I am, of course, making a broad assumption here. My 400 does suffer from the #3 drop out.

Cheers,
Dave.

Detlef Kunkel

Dave,
although the sensors etc are physically interchangeable, the software is NOT.

The timing and advance curve between the 150 and 215 / 250 is quite different, a use of the "blackbox" (that contains the software) on the wrong enginge can lead to totally destroyed engine.
I would never recommend to use it on another engine unless extensive test bench verfication is being made.

mogman

Thank you, Detlef.
It sounded like a simple idea[]
It would be interesting to know how many 400's there are and if it would be worthwhile for the company, who manufactures the ignition, to include the 400. Mine is ser.# 154, purchased in Nov. 2010

Cheers,
Dave.

jairaksinen

Today I was able to do maiden flight with my new Corsair and Moki 250. Ground tests showed that it was loosing one cylinder when going below half throttle. It was noticed that the high needle was about 1 turn too rich. So it is possible to get really rich conditions without electric pump. Anyhow, when leaning the mixture all the cylinders seems to be firing.

Previously I had some issues with too rich mixure in flight but it went away after installing velocity stack from TBM. Static RPM with Menz S 32x20 gave around 4300 and in flight it unloaded to 5670 RPM. So I'm thinking at the rpm's I'm loosing Moki's famous torgue. I suppose I'll move to three blade propeller.


Here a secong maiden video

http://jarkko.pictures.fi/kuvat/f4u_...t/P1030682.MOV

We had a speed gun to get some idea on the speeds... 219kmh. the inflight temps showed 115 C for the top cylinder and 100 for the #3 cylinder. and this is without baffling.

I just love the Moki engine.

Growler84

My Feedback: (8)

My humble suggestion is you reduce the inflight RPM below 4500 to stay away from the 5000 RPM maximum, which is the point where you will start throwing pushrods. You stated it perfectly, you are outside of the engine's torque curve at the RPM your engine is running. We are running a 32-inch Solo 3-blade propellor with the pitch adjusted for 3500 RPM on the ground and the most RPM we have seen the engine unload to in the air is 4100. The maximum airspeed we have recorded from our onboard telemetry is 110 mph/176 kph. The maximum recommended speed for the CARF Corsair we are flying is 125 mph/200 kph so we strive to stay below that speed. To us the CARF Corsair/Moki 250 cruising by at 85-90 mph looks and sounds very scale, which is our modeling objective.

Congratulations on your new model/engine, I'm positive you will have many hours of enjoyment from both.

Regards,

jairaksinen

Well luckily this is not a Carf corsair but a Don smith 1/4 scale.

What would you say that the pitch is roughly with your 32" prop? I've been planning of getting me a Fiela 3 blade. Would 32 x 14" lower the RPM's to the mentioned 3500?

Growler84

My Feedback: (8)

Very good, nice to not have to worry about maximum airframe speed limits.

It has been a while since we tuned the engine/prop combination but 18 inch pitch comes to mind as the setting we adopted.

We are also running high heat range spark plugs that Goetz Volgelsang recommended ($15US each) and they are fantastic. We have been running them for more than 10 hours and have never seen wet oil on any of the plugs (yes, that includes # 3 and #4). The only oil evidence we have noted is a light carbon coating that flakes right off when you brush it with a nylon toothbrush.

Have fun and watch the RPM, think Pratt and Whitney R2800 sound, NOT Ferrari!

stivvy

Hi Greg

What type of high heat plugs are you using - would like to give them a try.

Steve

Growler84

My Feedback: (8)

Denso U20M-U is printed on the porcelin "FK" is stamped on the metal under the hex head. The Denso U20M-U is a replacement for the NGK CM-6 we are all used to. However, the "FK" identifier means (according to the EU Denso catalog) "Super Ignitable Plug". My online searches for the FK variant of the U20M-U always leads to the EU, I have not been able to find the FK variant in the US (I really didn't try that hard). If the FK plugs are EU only that would explain their $15US price from Goetz Vogelsang. You can buy U20M-U plugs from sparkplugs.com here in the states for $3.49 each...I doubt these are the FK Super Ignitable Plugs. By-the-way, Denso lists the U20M-U as obsolete with no replacement but when you put them in your cart it takes you to sparkplugs.com where you can buy them (just to see, I ordered a few).

One more note, the plug also has four crosses stamped on it, which indicates a high heat range.

I think the FK plug is a EU plug, the only place I know to get them here in the US is from Goetz Vogelsang. I'm sure someone in RCU land with more time on their hands can find other sources, my head hurts now though so I am done.

... just get them from Goetz Vogelsang

wingstrut

It sounds like the plugs may be IRIDIUM, if that is the case then the price is about right.

Jaketab

My Feedback: (2)

I tried to reseach the EU plugs and I too came down with a head ache.
NGK CM-6 beside a Denso U20M-U. The base of the Denso plug reads " Denso Japan JK ++++ "
Not sure I can detect that much difference in performance between the 2 plugs.
The #3 cylinder may come up to temp and miss less with Denso - but it could be that I have the engine run in and turned better now.

Why not just buy one of the $15.00 EU plugs and run it #3 problem child cylinder????

J Tab

Laurence-RCU

I have the RCS 215. Forums suggset cleaning the clear tubing that runs from the carb. to the pump. There is the blue ring at each fitting which is what some refer to as a, I believe, Festo fitting.
How do I make the disconnect? And re-connect?

Ragards,

Laurence

MarkShapiro

My Feedback: (52)

It's very simple, Lawrence. While pushing the blue "ring" in toward its black housing, gently pull the tube out. To reconnect the tube, simply push it back in to the blue ring until you feel a slight click. When putting the tube back in, do not push the blue ring in as you did when removing the tube.

Laurence-RCU

Many thanks Mike.

Is this site great!!!!!!!

Regards,

Laurence

Growler84

My Feedback: (8)

Reference the idea of running the hotter Denso plug just in the #3 cylinder. This is exactly what Goetz Vogelsang recommended, but being the kings of overkill, we elected to install them in all 5 cylinders.

Phil just recieved 5 more hot plugs for his other 250 from Goetz. These are yet again different: U20M-U "JK" part number 6079, the big difference being these are U-groove plugs. This is the plug Jaketab showed in his photo.

stivvy

Hi guys,

I have researched the plug situation directly with Denso and have had email correspondence from them regarding a hotter plug.

The Denso U20M-U is a direct replacement for the NGK CM-6 and according to their specification has the same heat rating as the NGK, and is not a hotter plug.
The Denso reference 20 (U20M-U) refers to the heat rating, which is the same as the NGK heat rating of 6 (NGK CM-6).

Denso advise me that they do not have a hotter replacement for the U20M-U and, as has been mentioned in an earlier thread, they have now discontinued this plug due to low demand.

According to Denso the FK (super ignitible plug) is not available in the size we need (FK is 14mm dia thread, we need 10mm dia).

So - I do not think the U20M-U is much different to the NGK plug, although it might be a higher quality plug, hence the possible increased performance. Then again it might be all in the mind ?

I have ordered a single U20M-U from a supplier here in the UK and see if this helps the No3 issue.

Anybody have further information on this ?

Regards, Steve

oy4310

Please leave a link to the UKsupplier.

stivvy

The company that I have ordered a plug from is :

Camskill Performance & Tyres

Pottery Rd
Off Coach Rd
Whitehaven
Cumbria
CA28 9BZ
United Kingdom

Telephone number; Internet PARTS Dept.
01946-518201 (0044-1946-518201)

http://www.camskill.co.uk/m18b0s1383p5286/DENSO_SPARK_PLUGS_NIPPON_DENSO_SPARKPLUGS_-_U20M-U_-_6079_

Due for delivery this week, total cost inc postage £5.00 sterling.

There are many other companies shown on the internet, all similarly priced.

Steve

oy4310

Thank you

wingstrut

Steve, That is what I came up with, that the U-20 is a direct replacement for the CM-6, I was trying to find out if the Denso plug may be made out of Iridium which may allow it to be considered a (super ignitable plug), and one that would not deteriorate,
I studied their plug chart and couldn't find that it was. Why chase after a plug that the company discontinued, lets hope that NGK doesn't discontinue their CM-6.
And you are correct, the number is the heat range, the letter designations tell the thread size, length of thread and basically the dimensions and certain features of the plug.
The CM-6 and the U-20 are the same plug according to Denso's chart..............Ron

stivvy

Hi Ron,

Think that we both fully agree - not much difference between the two plugs.

I have now received the Denso U20M-U plug so will see if it helps.
The only benefit that I can see is the "U" groove which is ground into the electrode - supposed to increase the engine performance, but we will see.

Steve

Jaketab

My Feedback: (2)

Link to Denso U20M-U supplier in the US.

http://www.quickieparts.com/spark-pl...s-ngk-cm6.html

J Tab