T

trib

Well Known Member
Not sure if I have a problem or not. My engine (an ECi I assembled), typical O-360, carb, 8.5:1 compression pistons, lightspeed 2 and mag for ignition, fixed prop, primer to 3 cyl with electric solenoid switch. When I start it cold, I use the lightspeed and the mag is off. I hit the starter and then basically hold the primer switch on until the engine starts (probably about 15 sec). Once it starts, I turn the mag on. The engine runs great and will exceed the 2700 rpm limit on the prop in level flight at 2500'. Once warmed up, no primer is needed and the engine starts in about 5 sec. I initially thought this was a cold weather thing, but now that temps are in the 60's I've tried going back to no primer, and also tried with 5 sec of primer, but still have to hold the primer on while cranking to start it. I can definitely live with this, but just wanted to throw it out there for any ideas.

thanks

By the way, 40.3 hrs on the airplane and securing Phase I until I get some aerobatic training, when I'll put it back to get those added to the limitations (only rolls so far) :)
 
I have an O-320 and my start procedure is to first turn on the electric boost pump, let it pressurize the fuel system, then for first cold weather start of the day I push the primer button (electric primer system like yours) for 6 or 7 seconds then stop priming and turn off the boost pump. Then I crank the engine over with about 1/4" throttle open and the engine typically fires up on the second prop blade. When the engine is warm I only prime about 4 seconds using the above same procedure.
 
trib said:
Not sure if I have a problem or not. My engine (an ECi I assembled), typical O-360, carb, 8.5:1 compression pistons, lightspeed 2 and mag for ignition, fixed prop, primer to 3 cyl with electric solenoid switch. When I start it cold, I use the lightspeed and the mag is off. I hit the starter and then basically hold the primer switch on until the engine starts (probably about 15 sec). Once it starts, I turn the mag on. The engine runs great and will exceed the 2700 rpm limit on the prop in level flight at 2500'. Once warmed up, no primer is needed and the engine starts in about 5 sec. I initially thought this was a cold weather thing, but now that temps are in the 60's I've tried going back to no primer, and also tried with 5 sec of primer, but still have to hold the primer on while cranking to start it. I can definitely live with this, but just wanted to throw it out there for any ideas.

thanks

By the way, 40.3 hrs on the airplane and securing Phase I until I get some aerobatic training, when I'll put it back to get those added to the limitations (only rolls so far) :)
Click to expand...

Trib... I sent you a PM...
 
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Starting a Lycoming is darn near an art, seems every engine has a mind of it own.

Try using slightly different procedures to find what works best. If I get just the right amount of prime fuel into the intake, the engine will start on the first blade turn, hot or cold.

The trick is getting it down right everytime and I still have not figured that out. I can get it running every time but I don't like having to crank it 8 or 10 blades to get it to fire off.

When I do get it down, I won't share the trick because it probably won't work with your engine anyhow. :)
 
I have the same setup. But I took out the primer. Use electric pump to ensure system is "full" then off.

Start cranking the engine then a quick pump of the throttle. Usually starts although sometimes it takes two or three throttle pumps while the prop is turning.
 
Mag & Lightspeed both ON

I do it like Ron, Run the boost pump until it slows, 1 or 2 quick pumps on the throttle while cranking and she fire right up - Hot or Cold.

Once in a while I don't get it right the first time. If it takes more than a few seconds on the starter, I give it a rest for 30 seconds and do it again.

I also don't have a primer system but rarely fly when outside temps are below 40F.
 
look for a problem

Tim,
I have the same set-up except C/S prop.
If I held my primer for 15 seconds I would think I would flood it.
Sure sounds like you NEED the primer to start it and that isn't right in 60 degree weather. Look for some problem. I'm sure since your engine is new, then you most likely have a new carb as well. I might think about the starting circuit or low speed circuit of the carb and make sure it is set up correctly. How about idle and idle cut off etc.
I'm also assuming you have the EI on the left and standard mag on the right, without impulse coupling? That should be giving you "0" timing on the EI for starting or something close and the mag would be firing at 25BTDC so you leave that off until after start up, which is recommended to avoid kickbacks.
Good Luck. You got me thinking here.
 
O-360 Hard To Start

I have found that on my O-360 if the mags are the least bit out of time it makes the engine hard to start.

I have no primer system and almost never have a problem starting my O-360 (provided the mags are timed properly). Here's my system:

Cold Start:
Master on, Mixture full rich, Fuel pump on, 2-3 full pumps of the throtle and leave throtle 1/8" open. Turn the key and she'll usually fire on the 2nd blade!

Hot Start.
Master on, Mixture full lean (off), Fuel pump on till it slows, Fuel pump off, 1/2pump of throtle and back to 1/8" open, Turn key and as the prop starts to spin, slowly push the mixture in (toward rich). When she likes it she'll fire (everytime)!

Tommy Walker
RV-6A, N 350 TW
O-360 FP, 498 Hrs & "Climbing!"
 
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twsurveyor said:
ICold Start:
Master on, Mixture full rich, Fuel pump on, 2-3 full pumps of the throtle and leave throtle 1/8" open. Turn the key and she'll usually fire on the 2nd blade!
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This gets brought up from time to time, and because it is a safety issue, I'll mention that when you pump the throttle (with an accelerator pump tat squirts fuel, as on an 0-360) without cranking the engine to create a suction (to draw the fuel into the cylinders) you are creating a puddle of fuel in your airbox. If you get a backfire, there's a good potential for a fire!

I always prime with my accelerator pump, but ONLY when the engine is cranking (to draw the fuel into the cylinders). I try to rarely give advice, but in this case, I do urge caution.

Paul
 
Hard to start

Good advise Paul. I may need to amend my "Cold Start" procedures. Although I've been starting Lycomings like this for 25 years now and never had a problem, the next start could "be the one". I'll try the "spin & pump method" tomorrow AM.

Your never too old to learn something new and that's what this forum is all about! ALWAYS SAFTEY FIRST!!

Tommy Walker
RV-6A, N 350 TW
498 Hrs. & "Climbing!"
 
I started doing the "only pump while turning" when a plane near me caught on fire when it was being started. Luckily, fast action by the attendant in the terminal building saved the day (and the plane and the fuel pumps). The attendant had the fire extinguisher in action before the pilot even saw the flames.:eek:

Even though I learned about the risk of a fire during starting when I got my PPL, this incident made me realize just how real the risk is.
 
Ironflight said:
I always prime with my accelerator pump, but ONLY when the engine is cranking (to draw the fuel into the cylinders). I try to rarely give advice, but in this case, I do urge caution.

Paul
Click to expand...

I strongly agree with Paul. I will not pump the throttle unless the engine is cranking (and at a healthy rotation speed). Doing so with a nearly dead battery can give you a damaging kick back.
 
Tim, I have the same setup as you (exactly, with the exception of me using dual P-mags). I do the following, hot or cold weather, doesn't matter - works every time:
- Fuel pump on until pressure comes up
- apply the primer solenoid for 6 to 8 seconds (warm weather is 6 seconds, cold is 8) [Note: if your panel is wired like mine, then you'll have the fuel pump running when you apply the primer. Otherwise, shut off the elec. pump AFTER you prime]
- open the throttle 1/4-inch
- start

Let me know if you find a better way to do it.
 
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I have an 0-360 carbed with dual Slicks no primer system, fp prop...

Cold start:
Boost pump on, pump throttle 2 or 3 times while cranking... usually starts right off....

Hot start:
Leave throttle closed & mixture at cut off as when shut down, boost pump on, start cranking & slowly push mixture in.. fires right off when it likes the mixture..
Sheldon
 
I live in Canada. I have no primer even installed on the plane. Spin and pump works every time. The engine usaully starts about halfway through the second push.
 
And the winner is...

Finally got to the airport after being away for a week. The common thread from everyone's advice seemed to be that I shouldn't be leaving the electric pump running after pressure was up as I had been. During my startup procedure it is often running for a minute or so before I actually hit the starter.

So I... just before starting, turned on the pump, as soon as pressure was indicated on the EMS hit the primer solenoid for a 5 count, then released and turned off the fuel pump. Hit the starter and the engine started after only a few blades as nicely as you could hope for:). Problem solved. Apparently leaving the pump running was somehow forcing fuel and to some extent flooding the engine.

Thanks again guys!!
 
I took my primer system out a few years ago because I never used it. Two pumps after the first blade and it will fire right up with the boost pump off, hot or cold. Turning on the boost pump on a carbed engine for start will make absolutely no difference since the carb bowl is full of gas anyway. If you operate the throttle rapidly with the carb on the bench and with the bowl full of fuel the accelerator pump will shoot a stream of fuel 20ft into the air. Primers are completely unnecessary when the carb has an accelerator pump.

About a year ago I watched a buddy of mine start an F8F Bearcat when it caught on fire with flames going all the way back to the cockpit. He kept cranking which put out the fire...had he stopped cranking one of only six flying Bearcats would have been lost.
 
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