Hard to start O-360

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andy
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Re: Hard to start O-360

Post by andy »

stevesMaule180, you didn't mention not preheating in your original post. I always preheat my O-360-C1F before starting when the temperature is below 50F. It's difficult to start otherwise and there's a risk of running the battery down or overheating the starter motor as well as possible backfiring due to unburned fuel. I was using a portable propane heater with a custom built duct/SCEET arrangement. That works very well but requires me to bring the propane cylinder back and forth from home in my car since the airport won't allow flammable fuels in the rented T-hangar except what's in the airplane's tanks. A year ago I bought an Aerotherm Deuce electric preheater in case I ran out of propane or forgot to bring it. That has turned out to work well with the addition of a Kennon cowl blanket. It doesn't get the engine as warm as the propane heater but the oil temp is around 70F when I start the engine and it starts well with hangar temperature in the 20s. I turn it on before preflight and by the time I'm done, the airplane is ready to start. The insulated cowl blanket helps a lot.
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Re: Hard to start O-360

Post by stevesMaule180 »

Never heard of frosting plugs, but it does kinda make sense!
Possibly ‘fine wire’ plugs would be better on lowers, like another person mentioned.

Thanks,
Steve
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Re: Hard to start O-360

Post by Kirk »

3 thoughts on this thread:

1)Someone mentioned “morning sickness” and the possibility of a stuck valve. That to me seems to be the biggest impact on safety of all the possibilities. It also seems like one of the more likely issues. I couldn’t find the original Lycoming article but here is a good one from AvWeb that covers it all:
https://www.avweb.com/ownership/dealing ... ck-valves/

2) A tip I picked up on this forum years ago was that pumping the throttle in addition to priming increases the possibility of backfire and carburetor fire since you are adding raw fuel at the carb vs straight to the cylinders with prime. Made sense to me, something to think about.

3) Frosted plugs seems pretty unlikely. That issue really only seems to come up in extremely cold weather. I’ve only seen it once after pulling an airplane out of a heated hangar then trying to start after sitting outside for 30 minutes in -40 temps.

Hope this helps and hope you get to the bottom of this.

Kirk
Last edited by Kirk on Sun Jan 23, 2022 12:41 pm, edited 1 time in total.

asa
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Re: Hard to start O-360

Post by asa »

While I agree that preheating is an excellent thing for long term engine health and makes starting easier, I would be concerned if my O360 was difficult to start below 50F.
andy wrote:
Sun Jan 23, 2022 3:37 am
stevesMaule180, you didn't mention not preheating in your original post. I always preheat my O-360-C1F before starting when the temperature is below 50F. It's difficult to start otherwise and there's a risk of running the battery down or overheating the starter motor as well as possible backfiring due to unburned fuel. I was using a portable propane heater with a custom built duct/SCEET arrangement. That works very well but requires me to bring the propane cylinder back and forth from home in my car since the airport won't allow flammable fuels in the rented T-hangar except what's in the airplane's tanks. A year ago I bought an Aerotherm Deuce electric preheater in case I ran out of propane or forgot to bring it. That has turned out to work well with the addition of a Kennon cowl blanket. It doesn't get the engine as warm as the propane heater but the oil temp is around 70F when I start the engine and it starts well with hangar temperature in the 20s. I turn it on before preflight and by the time I'm done, the airplane is ready to start. The insulated cowl blanket helps a lot.

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Re: Hard to start O-360

Post by Andy Young »

asa wrote:
Sun Jan 23, 2022 12:40 pm
While I agree that preheating is an excellent thing for long term engine health and makes starting easier, I would be concerned if my O360 was difficult to start below 50F.
andy wrote:
Sun Jan 23, 2022 3:37 am
stevesMaule180, you didn't mention not preheating in your original post. I always preheat my O-360-C1F before starting when the temperature is below 50F. It's difficult to start otherwise and there's a risk of running the battery down or overheating the starter motor as well as possible backfiring due to unburned fuel. I was using a portable propane heater with a custom built duct/SCEET arrangement. That works very well but requires me to bring the propane cylinder back and forth from home in my car since the airport won't allow flammable fuels in the rented T-hangar except what's in the airplane's tanks. A year ago I bought an Aerotherm Deuce electric preheater in case I ran out of propane or forgot to bring it. That has turned out to work well with the addition of a Kennon cowl blanket. It doesn't get the engine as warm as the propane heater but the oil temp is around 70F when I start the engine and it starts well with hangar temperature in the 20s. I turn it on before preflight and by the time I'm done, the airplane is ready to start. The insulated cowl blanket helps a lot.
Agreed. While I have seen Continental IO-360s that were really hard to start anywhere below 50°F, my experience with Lycoming O-360s is that they will always start very easily without a preheat, even in temps well below where it’s a good idea, wear-wise.

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Re: Hard to start O-360

Post by stevesMaule180 »

Ok the O-360 is starting better now thanks to all the suggestions.
Turns out I was too worried about flooding the engine, and one or two primes not enough after cold and sitting for a couple weeks.

Also, just leaving throttle 1.5-2.0 turns (from full closed) helped ‘do the trick’. I had the throttle too far open, so not enough ‘suction’ to get fuel coming out of the jets.

Thanks for all your comments!

Stephen
Passing the faster planes, as they re-fuel ðŸ˜￾

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Re: Hard to start O-360

Post by Andy Young »

Good to hear!

Yeah, I find that three to four shots (depending on temperature) is about right on a cold engine.

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