engine rebuild service?
 

hi all,
i am just getting back into r/c planes with a hobbico nexstar plane. while at work a co-worker i was talking to tells me that her late husband who had passed 6 years ago flew r/c planes and that i was welcome to all of them if i would just come and get them. after spending this saturday bringing these home and taking inventory there are 7-8 engines from O.S., super tigre, etc that are in good condition but feel all "gummed up" i guess you could say when you turn over the engines. there are also about 10 of the little cox tiny engines that look pretty simple that i would like to rebuild as well since i used those in my youth. i think i could rebuild the cox engines, but not the larger engines. i doubt the larger engines need much more than a disassembly, cleaning, and tuning. so i guess my question is, is there a company or service out there that can get these engines back into flying condtion and clean them up and tune them for me that doesnt cost an arm and leg? thanks for any input -matthew

RE: engine rebuild service?
 

I wouldn't be disassembling them unless your just compelled to do so? You will more than likely do more harm than good?

Just remove the back plates and flush them out with a thin oil like 3 n 1 or WD-40 or Dexron Auto transmisson fluid

RE: engine rebuild service?
 

The first thing I would do is to sqirt some new fuel into the carb and flip it over a few times. More than likely they will just loosen up and be good to go

RE: engine rebuild service?
 

Exactly. Would try some fuel in the carb, down the glow plug hold and through the vent nipple. I would follow up using Marvel Airtool oil.

This may well clean things up. Also you may need to take out the needle valve and pass a pipe cleaner soaked with lighter fluid or fuel through.

You can usually fix a gummy engine without a rebuild.

Tom

RE: engine rebuild service?
 

I picked up an old Super Tigre .40 in a trainer at a garage sale. The motor was stuck. I soaked it in Kroil overnight. The next day it turned over just fine, but a buch of junk came out of the motor. I took the backplate off and flushed it with fuel. Then I tried to start it. It would run wide open or not at all. I pulled off the carb and cleaned and checked the spray bar, and set the low speed needle valve per the Super Tigre web site. It would start and idle, but would not transition smoothly to full throttle. Then, in searching for help on the internet I found the following advice about tuning these motors in a RJL .61 manual:

1> Start the engine and open the carburetor to the full open position, then adjust for peak R.P.M. with thehigh speedneedle.

2> Close the carburetor barrel slowly until the lowest possible speed is reached without the engine stopping.

3> Go to full throttle after about 10 seconds of idling. If the engine gains speed slowly, the idle mixture is too rich.
If the engine stops, the idle mixture is too lean. Turn the idle needle clockwise if mixture is too rich
and counterclockwise if too lean.

The engine will accelerate from idle to full throttle smoothly and instantaneously when properly adjusted.
The engine may not idle well at a low setting or accelerate as quickly until it is well broken in.
Turn the idle needle clockwise if mixture is too rich and counterclockwise if too lean.


This has helped me get some of my dad's old engines running again.

Joe