New Engine Start
#1
Thread Starter

My Feedback: (10)
I have a Tower Hobbies .75 engine mounted in the inverted position. Installed a remote ignitor in the fuselage. Followed instrutions on first time starting. When I remove the glow plug starter, engine dies. Tried adjusting carb, but with same results. Any suggestings?
#2
when the motor dies when the igniter is removed is way to rich. Are you breaking the motor in? if so this is normal. is it dying at open throttle or idle.
#4
Why are you trying to idle it during break in?
You don't need to idle it during break in. Run 2 or 3 tanks through it at wide open and do it a little rich--like any ABC engine.
As for the idle--AFTER you get it broke in--you need to set your fuel tank so that the centerline of the tank is even with the spraybar on the carb. Since you've mounted the engine inverted, your carb is most likely lower than the fuel tank now. The tank is going to siphon into the carb all the time. You'll have a difficult, if not impossible, time getting the carb properly adjusted for good idle and transition.
Either install an on-board glow driver:
http://www2.towerhobbies.com/cgi-bin...&I=LXDZ82&P=ML
Or, rip the tank support out and lower the tank down. You need to have the center of the tank even with the spraybar in the carb.
You don't need to idle it during break in. Run 2 or 3 tanks through it at wide open and do it a little rich--like any ABC engine.
As for the idle--AFTER you get it broke in--you need to set your fuel tank so that the centerline of the tank is even with the spraybar on the carb. Since you've mounted the engine inverted, your carb is most likely lower than the fuel tank now. The tank is going to siphon into the carb all the time. You'll have a difficult, if not impossible, time getting the carb properly adjusted for good idle and transition.
Either install an on-board glow driver:
http://www2.towerhobbies.com/cgi-bin...&I=LXDZ82&P=ML
Or, rip the tank support out and lower the tank down. You need to have the center of the tank even with the spraybar in the carb.
#5
Senior Member
My Feedback: (1)
If at all possible, the BEST position for an engine is sideways. In that position the spray bar is reasonably close in height to the center of the tank.
FWIW - MANY of the Tower engines are prone to airleaks. This will be most noticable during transition and shut down (or lack thereof). The MAJORITY of the airleak problems can be solved with a little silicone between the backplate and the crankcase and on the carb o-ring.
FWIW - MANY of the Tower engines are prone to airleaks. This will be most noticable during transition and shut down (or lack thereof). The MAJORITY of the airleak problems can be solved with a little silicone between the backplate and the crankcase and on the carb o-ring.
#6
it will not idle until about 2 tanks. lean out the low end about 1/2 turn. close the high end needle and open it 2 turns. open the throttle 1/4 open then advance to full as soon as it gets going and leave it there. tower motors actually instruct the pinch method of break in. AT this point the motor shouldn't run with the igniter removed. every 30 second or so pinch the fuel line so the motor speed up to full RPM then release do this throughout the tank.
half way through the second tank start leaning it out it should start surging from a lugging tone to a high pitch 2-stroke tone. lean a hair more and remove the igniter. finish the reset of the tank with a quick pinch every 30 seconds. The third tank lean the motor out to peak RPM then back off 500 RPM 5-6 clicks and let it run wide open. half way through bring it to a high idle and bring it down slowly till it dies. open the throttle a hair and restart.
pinch the fuel line and listen to the motor. if it speeds up and dies it's rich. lean out the low end.
if it just dies it's lean. richen the low end. restart and repeat. backing the throttle a little more until you get a decent idle.
it's still not going to idle well until your second gallon of fuel. advance to full and reset the high end. then back to idle and redo the low end. it's a delicate balance but once it's right their no stopping em.
half way through the second tank start leaning it out it should start surging from a lugging tone to a high pitch 2-stroke tone. lean a hair more and remove the igniter. finish the reset of the tank with a quick pinch every 30 seconds. The third tank lean the motor out to peak RPM then back off 500 RPM 5-6 clicks and let it run wide open. half way through bring it to a high idle and bring it down slowly till it dies. open the throttle a hair and restart.
pinch the fuel line and listen to the motor. if it speeds up and dies it's rich. lean out the low end.
if it just dies it's lean. richen the low end. restart and repeat. backing the throttle a little more until you get a decent idle.
it's still not going to idle well until your second gallon of fuel. advance to full and reset the high end. then back to idle and redo the low end. it's a delicate balance but once it's right their no stopping em.
#7
I have a Tower .75 and it is my most reliable engine. This thing will scream -- but you have to break it in properly. The manual that came with the engine should be followed. Basically what has been stated here earlier. Start it and move to full throttle. Let it runs a rich as you can without it going into 4-stroking (very bad for an ABC engine). It should smoke like crazy (I always break in my engines on the bench -- when done in an airplane you will deliver as much oil and fuel to the airframe as you would in about 30 normal flights). After a couple of tanks then you start the pinch and mid range. 5 pinches and if it increases then a couple of click leaner for 30 seconds then back to mid for 30 seconds. Back to full, 5 pinches and if all increase, then click again. You do this over and over until there is no more increase and a pinch will drop RPMs back off 1/4 turn and finish that tank cycling from high (30 seconds) to mid (30 seconds). Now your ready to check your low end. I have two tower engines and have never needed to reset the low end idle.
One thing that you will need to make sure on this engine is no Air Leaks! When installing the carb, it must be pushed down during tightening. It has a very big O-ring and if not seated it will blead air and you will never get the low end set.
By the way, this engine will scream with a Top-flite 12x6 Simitar and also really works well with APC 12x8 for speed. I have a Super Sportster with a Tower .75 which turns a 12x6 at nearly 15,000 RPMs. Starts with a flip and has never died in flight in over 80 flights.
One thing that you will need to make sure on this engine is no Air Leaks! When installing the carb, it must be pushed down during tightening. It has a very big O-ring and if not seated it will blead air and you will never get the low end set.
By the way, this engine will scream with a Top-flite 12x6 Simitar and also really works well with APC 12x8 for speed. I have a Super Sportster with a Tower .75 which turns a 12x6 at nearly 15,000 RPMs. Starts with a flip and has never died in flight in over 80 flights.




