ORIGINAL: Free Bird
Free Bird et al,
Just got off the phone with Hank at Sonic Tronics. He indicated that our problems were as a result of not having enough amperage to drive all three cylinders. He said we should have 1000 mA for each cylinder and that was why my 2300 mA 4-cell was not enough to keep things hot. I am going to try a 4200 mA 4-cell that I have but it will be a couple days before I can report.
He also said that the only reason the 5-cell did not blow out a glow plug, besides being very lucky, was because I left part of the “servo wire” on the battery, which offered enough resistance to lower the 6 volts. Battery not being charged to maximum and only run at start and 1/3 or less throttle also helped.
Hope that helps, buying a new 3000mA or greater 4-cell battery is the cheapest of solutions so far presented. BTW, Hank invited anyone to call if they had more questions.
jimm
jimm,
While all of this sounds good, my experience has been contrary to the above. I'm using a 4-cell 4500 nimh (I know the instructions say to use nicds). However, none of my LHS had nicds of this size on hand, only nimh, so that's what I used. But, let's think about this for a moment, each plug requires 1.5v and about 3amps to be properly lit. That means that the pack needs to supply 4.5v and around 9amps continously for a 3-cylinder engine. Under these conditions, I think a 4-cell 4500 pack is already over taxed, hence the low output on the plugs. I think the way to go is to use a regulated 2-cell 25c lipo. Voltage would be around 5v (a 4-cell hot off the charger is over 5v), and the pack would be able to supply the necessary amps without any problems. I'll be checking with my LHS this weekend to see if they have the necessary stuff.
Hill202: A Saito 150 IMHO, is way more than the model needs. Mine with the 170R3 was a lot faster than scale and I flew the first flight at around 1/2 throttle.
More to come..........
FB
Thanks Free Bird. I think I'll go with a OS 120, that is if my LHS has not sold the plane. I do have a OS 95, that might would be enough.