61RF-P ABC Running in problems
 

I have a brand new 61RF with pump which I am trying to run in ... problem is that I can not get the engine to run stably when it is rich ... the engine starts well at idle with about needle open about 1.5 turn, and when I open the throttle, it goes to full throttle but when I try to adjust the needle so as to make the engine run rich at full throttle, it either becomes so rich that it stops by flooding or it runs at around 10,000 RPM ... I can not get it to run stably below 10,000 RPM - it just goes too rich and stops.

I am using an APC 13x8 with 80:20 Methanol and castor oil fuel for running in as I do with all my engines.

Any suggestions?

RE: 61RF-P ABC Running in problems
 

spaceship1, how many tanks of fuel have you run through this engine?? Most engines will not give the performance or throttle transition untill well run in. Using the engine manual as a guide run this engine in, then do it again, it will improve after a good gallon of fuel.

RE: 61RF-P ABC Running in problems
 

With the O.S. Max .61 RF-P engine, we usually prop it so that it will turn in the high 11,000's at full throttle when leaned to peak.

With the pumped engine, we NEVER open the needle more than 1-1/4 turns out from closed. It will be too rich otherwise. Since you have the non-ringed version, advance the throttle to full and then immediately lean the engine so that it is running in "2-cycle" mode. Running it too rich will damage it and not allow it to break in properly.

Once the engine is run-in enough to lean to peak, you want to lean the engine as far as possible without detonation or RPM drop and leave the needle there. DO NOT lean to peak and richen it.

You should have no problems with your 80:20 fuel. Because you have no nitro, you may want to make sure you're using an O.S. #8 plug or even the #a# plug, which is a little hotter than the #8.

You may wish to examine the O.S. FAQ pages:

http://www.osengines.com/faq/index.html

RE: 61RF-P ABC Running in problems
 

Dear Bax,

Thanks for the reply, you have mentioned that I should open the throttle to full and immediately lean the engine so that it is running in 2-cycle mode ... problem is that I expect that the engine should be around 6000 to 8000 rpm for running in, but this engine does not want to run below 10,000 which I think is too high for break in????

If I try to bring it down from 10,000 by opening the needle at full throttle, it suddenly goes too rich and I have to kink the fuel line to keep it running ... closing the needle again beings it to around 10,000 suddenly ... This is my first experience with this type of a pumped engine so I do not know if this is normal behavior ...

Please also consider that where I am the current ambiant temperature is around 35degC. I am using #8 OS plug, and an OS pipe.

Any further suggestions?

RE: 61RF-P ABC Running in problems
 

You are trying to run the engine too slowly. With a 12 x7 APC prop, you start the engine with the high-speed needle at about 1-1/4 turns open, and advance to full throttle. Immediately lean until it just stops running in 4-cycle mode. You h ave the non-ringed engine. Running it too rich will ruin it, not allow it to break in. Don't worry about RPM. Just accept whatever RPM you get.

The pipe won't be tuned, of course, because the engine's not broken-in yet. Just make sure the tuned pipe system is too long for the RPM you're running.

RE: 61RF-P ABC Running in problems
 

Dear Bill,

Again, thanks for your reply and for the advise. Just out of curiosity and for the sake of learning, I have always broken engines both ringed and ABC type by running them rich (4 stroking) for the first 2 tanks or so (more than 2 tanks if engine hesitates to run lean) and then alternating between lean and rich until it holds lean steadily ... you mention that this could damage an ABC type engine? can you please explain how this might cause damage?

Have a nice day and thanks again for taking the time to answer my questions [8D]

RE: 61RF-P ABC Running in problems
 

Please see our FAQ on the subject. It applies to ABC as well as ABN engines.

http://www.osengines.com/faq/product-faq.html#q2

RE: 61RF-P ABC Running in problems
 

Thanks for the help Bill - really appreciate the time you took to answer the questions. The FAQ is very helpful, I should have read it in the first place!

Have a nice day [8D]