Surefly Mag / IO-540 Plugs Fouling

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Hunt-man

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Hunt-man
I had a Surefly SIM6L installed a few months ago at annual on the left side. I starts better. Don't notice any performance difference in flight. Same TAS. Fuel flow is higher but I also had a valve issue that was found and fixed and had the right mag serviced and timed.

I am having problems with the plugs fouling, during taxi I lean a lot, on approach with the mixture rich and ready for a go around, the plugs on the Surefly usually foul. I've started doing run ups prior to shut down to check the plugs, often I need to run it lean to clean them. The Surefly mag check is often slightly rough.

Should I change plugs? Tempest fine wire? Looks like I have Champion RHM38E massive with about 200 hours on them, since 2014 installation and just inspected at annual.
 
Someone confirm this, but wasn’t 2014 the time when champion had those crappy plug debacle ?
 
From the Surefly website; - "A slight engine stumble during mag-check is expected and normal. This condition is caused by a magneto switch that grounds both ignitions during the transition between left and right. A startup delay is designed into the SureFly to determine proper rotation. In many cases this condition can be masked by changing the cadence in which the switch is cycled."

Doesn't explain your fouling, but might explain the mag check stumble.
 
Hunt-man said:
on approach with the mixture rich and ready for a go around, the plugs on the Surefly usually foul.
Click to expand...

Maybe the FI version is different, but when I had an O540, the only time I was full rich was on takeoff or go around. All other times, I was leaned. Otherwise the plugs fouled.
 
WannFly said:
Someone confirm this, but wasn’t 2014 the time when champion had those crappy plug debacle ?
Click to expand...
Yes. Pull one of the Champions. Look down inside the plug. If you see a screw head, replace with appropriate Tempest.
 
Did you have fouling issues before the new mag ? When you remove the fouled plugs, are they oil fouled ? Older Champion plugs had issues with the some internal resistors going extremely high in value. Test the resistance from the contact inside the plug to the tip electrode..you should get a reading below 10k ohms...usually about 2k ohms. If the resistance is very high....say 20k or higher, try installing a different plug. If the plug tests ok, it can still have a broken ceramic somewhere that you cannot see. Make note of which plugs are causing issues...if you continue to have issues on the same cylinders, test your ignition leads. I suspect bad plugs...if you get a rough mag check, it is usually a fouled plug problem..a bad wire will not clear up with leaning.
 
Lycoming specified a very rich mixture at full rich for the carb on the O-540. You need to lean that thing almost all the time. We had the same issue on our R182, and I talked to the Precision Airmotive guy about it. They were the manufacturers of that HA-6 carb at the time (2006 or so).
 
Thanks for all the replies!
I'll order some new plugs. Tempest. At least I can eliminate the plugs as the issue.
I'm having to be way more aggressive with leaning since the Surefly mag was installed.
The roughness in NOT the stutter when switching between L and R mags, that is more of a skip and is of no concern.
There is very mild roughness on the left mag, often but not always. I suspect fouling.
I don't have the same mild roughness on my R Slick mag, that was just serviced. It never seems to foul or run rough on mag check.
My habit is to go full rich on short final in case of a go around, and lean again when I clear the runway, and that seems enough to foul it.
I now do a run up after landing, lean past peak, run at peak for a bit and still have issues with mild roughness.
So I'll try new plugs. Then look at the wires if I continue to have problems.

Appreciate the help! :)
 
Read the POH for that airplane. It will talk about leaning, and its advice will be somewhat different than you'd find in a 172 POH, say.

Also check the Lycoming O/IO-540 operator's manual. https://www.lycoming.com/sites/default/files/O & IO-540 Oper Manual 60297-10.pdf

Pay special attention to pages 3-4 and 3-5. Remember that temperature affects density altitude, and on warm days you might have to lean more than you're used to.
 
Dan Thomas said:
Read the POH for that airplane. It will talk about leaning, and its advice will be somewhat different than you'd find in a 172 POH, say.

Also check the Lycoming O/IO-540 operator's manual. https://www.lycoming.com/sites/default/files/O & IO-540 Oper Manual 60297-10.pdf

Pay special attention to pages 3-4 and 3-5. Remember that temperature affects density altitude, and on warm days you might have to lean more than you're used to.
Click to expand...

Thanks for that link. I read those pages. Good info. Full rich for take off and full power. I have a EGT / CHT x 6 gauge. Interesting to see below 75% to run at peak EGT, I try to run a bit rich, 25 to 50.
Before installing the Surefly I had to lean but now I'm having to be way more aggressive leaning. My problems are on the Surefly side, not the Slick mag side.
I called Tempest and they suggested a bigger gap, 28-30 instead of the 16-18... (Not sure what to do with the gap)
Surefly's website says to use the standard recommended gap. I'm waiting for a call back from Surefly to see if they have any suggestions.

Then I'll order some Tempest URHM38E plugs and see what happens.
 
Talked to Surefly.
Surefly suggests checking the harness, especially the springs under the cap, as they can get bent and not connect properly. Also the ends at the plugs.
Say's they have not had fouling issues with Surefly mags.
Also said a bigger spark plug gap is fine, as long as the mechanic is ok with it.
 
They are expensive, but replace the massives on the Surefly mag with fine-wires. Rarely do they foul.
 
Chip Sylverne said:
They are expensive, but replace the massives on the Surefly mag with fine-wires. Rarely do they foul.
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I think I have read somewhere surefly works best with fine wire when I was evaluating SureFly. I agree though with fine wire things are much smoother
 
Too late. Already ordered the massives... Surefly did not recommend the fine wire when I talked to them today.
I'll just guess that when I have problems with the massives, they'll recommend the fine wires and say I should have bought them in the first place. Ha! :)
I've got a date with my mechanic on Thursday and we will check the wiring and connections. New plugs for the Surefly when they arrive next week.
 
I've got about 100 hours on my IO550 with a SureFly and massive electrode plugs. No problems with fouling. Haven't heard that complaint from others either.
 
I am running Electroaire on two engines 0-360 and IO-540. Run fine wires on both EI's (massive on the mags) and do not have any issues with fouling with either engine. Of course I am not sure that the Electroaire will require exactly the same set up as the SureFly. Electroaire is pretty adamant about using fine wires.
 
I pulled the plugs. All had the slotted screw slot. #3 cylinder plug is oily. Annual was in February. #3 had 0 compression at annual. I had that one pulled, valve replaced and cylinder reworked back in February. The mechanic forgot to tighten the intake manifold bracket for #3. Ran very rough. Fine after he replaced the gasket and torqued the bolts for #3. I can see some scoring inside #3. I'm worried about #3. Will check compression and bore scope again. :(
New plugs here next week. Tempest massives.
Also found a 2/3 around crack in the exhaust pipe after a flight today. Will source that part tomorrow.
Oh my. Rains it pours, eh?
 

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I think you're missing 6 plugs. Obviously, you have two wet plugs. Which cylinders and top or bottom?

You may want to check the rest of your exhaust system. No sense putting a new part on a failing system.
 
Hunt-man said:
I pulled the plugs. All had the slotted screw slot. #3 cylinder plug is oily. Annual was in February. #3 had 0 compression at annual. I had that one pulled, valve replaced and cylinder reworked back in February. The mechanic forgot to tighten the intake manifold bracket for #3. Ran very rough. Fine after he replaced the gasket and torqued the bolts for #3. I can see some scoring inside #3. I'm worried about #3. Will check compression and bore scope again. :(
New plugs here next week. Tempest massives.
Also found a 2/3 around crack in the exhaust pipe after a flight today. Will source that part tomorrow.
Oh my. Rains it pours, eh?
Click to expand...

The oily plug,0 compression, and the crack stack should tell you some thing.
 
Domenick said:
I think you're missing 6 plugs. Obviously, you have two wet plugs. Which cylinders and top or bottom?

You may want to check the rest of your exhaust system. No sense putting a new part on a failing system.
Click to expand...

I only pulled the 6 that were related to the rough Surfly mag. 1,3,5 are bottom plugs, 2,4,6 are top plugs. #3 is the wet oily plug and is the bottom on #3. That cylinder, valve and valve seat were reworked less that 15 hours ago. #3 HAD NEW rings installed. The other Slick mag / plugs purr smooth and run fine.

The exhaust collector was replaced a few months ago at the annual, it had been welded many times before. Intakes / Exhaust manifolds looked ok at annual.

Tom-D said:
The oily plug,0 compression, and the crack stack should tell you some thing.
Click to expand...

What? That cylinder was reworked / repaired a few months ago. Its' in the upper 70's now.

Last night I had a mechanic over. We scoped the cylinders and valves and all looked good. The mechanic thinks #3 with its' new rings is still breaking in, causing the oily plug. We discussed how it would have been better to run mineral oil for the break in. But when it was repaired, I asked about that and I was told, just to run the 80 plus / avblend I had in there that was quite fresh. Next time mineral oil = but too late now.

We did a cold compression check and all were mid to high 70's, even the oily one.

I checked resistance on the 6 plugs. One would give no reading, the rest were under 3,000.

WILL CHANGE ALL THE PLUGS TO Tempest and see what happens. Plugs and pipe here next week.

Thanks for the help and comments. :)
 
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Hunt-man said:
I only pulled the 6 that were related to the rough Surfly mag. 1,3,5 are bottom plugs, 2,4,6 are top plugs. #3 is the wet oily plug and is the bottom on #3. That cylinder, valve and valve seat were reworked less that 15 hours ago. #3 HAD NEW rings installed. The other Slick mag / plugs purr smooth and run fine.

The exhaust collector was replaced a few months ago at the annual, it had been welded many times before. Intakes / Exhaust manifolds looked ok at annual.



What? That cylinder was reworked / repaired a few months ago. Its' in the upper 70's now.

Last night I had a mechanic over. We scoped the cylinders and valves and all looked good. The mechanic thinks #3 with its' new rings is still breaking in, causing the oily plug. We discussed how it would have been better to run mineral oil for the break in. But when it was repaired, I asked about that and I was told, just to run the 80 plus / avblend I had in there that was quite fresh. Next time mineral oil = but too late now.

We did a cold compression check and all were mid to high 70's, even the oily one.

I checked resistance on the 6 plugs. One would give no reading, the rest were under 3,000.

WILL CHANGE ALL THE PLUGS TO Tempest and see what happens. Plugs and pipe here next week.

Thanks for the help and comments. :)
Click to expand...

is easy to swap a couple plugs and see happens.
why did the stack crack?
 
Do you realize when you have overheated a cylinder the rings are the thing that show first?.
and when the temper of the rings is lost, they lose the ability control oil flow
be-careful you may have ruined a cylinder before it got broken in.

running it hard may not always be the best way.

there are compression rings and oil control rings, the oil control rings are the first to feel heat because they are the lowest on the piston, over heat them and they will lose their temper, then the ring collapse into the cylinder and too much oil is allowed to pass the rings, resulted in high consumption.
 
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Tom-D said:
is easy to swap a couple plugs and see happens.
why did the stack crack?
Click to expand...

I don't know why the stack cracked. I looked in the logs and couldn't find when it was installed. It could be 20 years old. It cracked on the outside of the bend, where the metal was stretched to make the bend. The collector I just replaced was old.
The fact that it cracked so quickly and such a large crack is concerning. No rust. The metal at the crack is much thinner than the end of the pipe.

Tom-D said:
Do you realize when you have overheated a cylinder the rings are the thing that show first?.
and when the temper of the rings is lost, they lose the ability control oil flow
be-careful you may have ruined a cylinder before it got broken in.

running it hard may not always be the best way.

there are compression rings and oil control rings, the oil control rings are the first to feel heat because they are the lowest on the piston, over heat them and they will lose their temper, then the ring collapse into the cylinder and too much oil is allowed to pass the rings, resulted in high consumption.
Click to expand...

The mechanic that looked at it said it was normal. He thought the rings would seal up.
I have not been running it hard. I keep on the rich side of peak in cruise, rich for TO, and only lean aggressively for taxi.
After some more hours we'll see if it breaks in or needs to be redone.
How many hours does it usually take for rings to settle in?
 
I've got about 150 hours on a Surefly. I had done a wider gap on the plugs at install. Pulled the plugs yesterday and they were very clean. The Surefly really has been a nice addition.
 
I changed the plugs for the Surefly. Replaced the cracked exhaust. Did a run up.
Surefly mag purrs like a kitten again. All is well in Comanche-land.
As far as plug gap, I just used the 18-19 the Tempest came from the factory with. It isn't that easy to open the gaps, and I forgot to order the special tool, and no one had it at the airport. All the spark plug tools I borrowed are for closing gaps, not opening them. If I have fouling problems on the Surefly I'll try a bigger gap, 28-30 was what Surefly said was working.

Thanks for the help.

Just to follow up, I'm not having any issues with "fouling" anymore on the Surefly or the Slick mag plugs. It was my bad plug on the Surefly side. I still need to lean on the ground but just not as much as I was. FYI
 
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