LOVE my J, HATE starting it.

[thomas1142]

OK! Complete frustration! I have read the threads about staring the engine when cold, warm, hot and even flooded. I have tried each of those approaches. I have read and reread the manual. Still have problem starting when it's hot, and this afternoon I had trouble starting it even after a two hour cool down.

what the heck is going on?

[KLRDMD]

3 minutes ago, thomas1142 said:

OK! Complete frustration! I have read the threads about staring the engine when cold, warm, hot and even flooded. I have tried each of those approaches. I have read and reread the manual. Still have problem starting when it's hot, and this afternoon I had trouble starting it even after a two hour cool down. what the heck is going on?

Your technique may be fine. It may be ignition related items that's the problem.

[Andy95W]

 

[M016576]

22 minutes ago, thomas1142 said:

OK! Complete frustration! I have read the threads about staring the engine when cold, warm, hot and even flooded. I have tried each of those approaches. I have read and reread the manual. Still have problem starting when it's hot, and this afternoon I had trouble starting it even after a two hour cool down.

what the heck is going on?

Mike Busch also has a great great article on starting aircraft engines- his is more related to big bore conti's, but many of the principles apply to the lyc 4's as well... I wish I had the link, I'd post it: maybe someone else does?

[Jeff_S]

That Mike Busch article may be confusing as there are some elements to it that are truly targeting the Continentals. There are a few pinciples in it that apply to any engine, though. Namely, if the engine won't cold start, add fuel. If it won't hot start, too much fuel.

But I agree with the reply above that says in the OP's case, perhaps it's time to have someone look at the engine. There could be some mechanical issues that will fix the problem. The IO-360 is usually pretty easy to start if configured correctly.

[LANCECASPER]

Of the three, Fuel, Air and Spark, I'd bet on Spark - either plugs, mags, timing, harness.

[kpaul]

This may have nothing to do with it, however I started having troubles getting my IO-360 to start.  I could not figure out what I was doing wrong.  Turned out it was a weak starter.  I learned it was the starter when it quit and I had to replace it.  The motor starts like a dream now.

 

[jasona900]

What is your hot start procedure?  For my J, my hot start procedure is similar to the cold start, minus a prime with boost pump.  For a cold start, I prime using the boost pump for 5 seconds with full throttle and mixture rich. To start, throttle is pulled about ½ inch from closed and mixture is full lean.  Engage the stater, and as soon as the engine starts, full rich with the mixture.  

I have had issues starting other fuel injected engines after an extended fuel stop in hot (90 degrees +) weather.  Could have been vapor lock, which in my experience, you would have to simply wait out. 

[jetdriven]

Cranking with the boost pump on eliminates vapor lock 

[thomas1142]

55 minutes ago, Andy95W said:

 

I viewed the same video, yup, so darn easy on tv.

[thomas1142]

21 minutes ago, kpaul said:

This may have nothing to do with it, however I started having troubles getting my IO-360 to start.  I could not figure out what I was doing wrong.  Turned out it was a weak starter.  I learned it was the starter when it quit and I had to replace it.  The motor starts like a dream now.

 

Hi Kevin, s that you flying around 54J today? Looks like a stop at Monarch is in order.

[Bob_Belville]

Keven mentioned possible weak starter. Problem could also be the battery or the plugs. A new Concorde RG 35 AXC and a set of Tempest fine wire plugs might end your frustration.  

If you have an EDM check to be sure you're seeing at least 13.8 V when the engine is running.

[jaylw314]

If your cold starts are fine and your problems are only on hot starts, it's probably technique.  My instructor suggested just flooding the engine after one failed hot start, it's just not worth the time, and it keeps your passengers from getting anxious

[Tommy]

Take a video of how you do your hot start and post it up here! Will give us a lot more info!

Cool down actually makes it harder to start because the vapour lock. Always warn your pax that it's a lot harder to hot start so they don't get anxious about it.

 

 

 

[ArtVandelay]

I push the throttle and mixture all the way in for 10+ seconds, this dumps the hot fuel, then I do normal hot start. This results in all my hot starts, whether they are 2 minutes like in Maxwells video or 25 minutes in the real world, consistent...I always start from the same state: hot engine and empty lines.

[kpaul]

8 hours ago, thomas1142 said:

Hi Kevin, s that you flying around 54J today? Looks like a stop at Monarch is in order.

I wish, I was stuck at work not flying. 

[Bob - S50]

Thomas,

Agree that if you have no problem with cold starts, it is technique.  If you have problems with cold starts, it could be the starter or electrics.  We have a 78 J with an A3B6D engine, Tempest fine wires, and a Skytec starter.  If that's similar to what you have...

Cold start:

Throttle open about 1/2", mixture full rich, boost pump for 5 seconds.

Mixture full lean, crank, when it catches, mixture smoothly half way to full rich, throttle back to 1000 RPM.

Hot start:

Same as above but no boost pump.

Warm start.  Try the hot start.  If it won't start the first time:

Throttle open about 1/2", mixture full rich, boost pump on just long enough to show pressure on the gauge (probably about 1 second).

Same cranking technique as cold and hot starts.

[Piloto]

I had a similar problem even with cold starts. Found out it was due to the electric pump not having enough pressure, just barely above the red line with full mixture and throttle. Replaced the pump and it start now on the first prop turn.

José

[thomas1142]

2 hours ago, Piloto said:

I had a similar problem even with cold starts. Found out it was due to the electric pump not having enough pressure, just barely above the red line with full mixture and throttle. Replaced the pump and it start now on the first prop turn.

José

Is it supposed to go past the red line? I get right up to it but definitely do not go past. 

[thomas1142]

16 hours ago, teejayevans said:

I push the throttle and mixture all the way in for 10+ seconds, this dumps the hot fuel, then I do normal hot start. This results in all my hot starts, whether they are 2 minutes like in Maxwells video or 25 minutes in the real world, consistent...I always start from the same state: hot engine and empty lines.

Boost pump off during the 10 seconds?

[Piloto]

2 hours ago, thomas1142 said:

Is it supposed to go past the red line? I get right up to it but definitely do not go past. 

Even though the pump sounds healthy it would be difficult to prime the engine with low pressure. Just replace the pump. My new pump reads 25 psi.

José

Edited September 17, 2017 by Piloto

[ArtVandelay]

Boost pump off during the 10 seconds?

Yes, BP off, if you have master on, you can watch fuel pressure drop, takes about 10 seconds, wait until it drops to 0, then you can do normal hot start: throttle 1/4-1/2", mixture cutoff.

 

It takes a few blades because it has to get fuel flow going again, I usually turn on the BP for a second to re pressurize the lines, I think needs less revolutions.

 

The big plus is there is no vapor lock, no doubt what state the engine fuel is in, it results in more consistent starts.

 

P.S. My AP came up with this method, he flys a 78J

[marky_24]

Try this,  

Before shut down bring the rpm's to 1200, tighten the friction lock so you dont bump it getting out.  Next pull mixture to cut off.  Then when you restart,  DONT TOUCH ANYTHING, just crank the engine.  5 blades or less the engine will fire,  briskly move the mixture to rich and bring rpm's to 1000. This has never let me down and i live where it gets to 110+ in the summers. 

 

[philiplane]

If you have Slick magnetos, and the engine starts fine cold but not hot, you may have a problem with the ignition coils. It is fairly common for Slick coils to lose continuity on the coil tab, which is where the distributor's carbon brush rides. This can be duplicated with the magneto off the plane. Heating the coil with a toaster oven or heat gun to 250 degrees duplicated the hot soaked engine condition. Testing for continuity through the coil will reveal a bad coil. You clip a multimeter lead to the tab, and the other to the inout, and apply pressure in various directions to the tab. I've probably found over 100 bad coils this way, after pilots report problems starting hot but never when cold. 

[Hank]

I have nothing to contribute to fuel injected hot start procedure since I fly an always-easy-to-start carbed model.

But I find threads like this, recurring periodically, to be in stark contrast to the frequently-offered opinion that the IOs are easy to start whenever a carb pilot mentions that our planes are so simple to crank . . . . .

Now back to your regularly-scheduled programming.