Need Help With This

Clarkie · #1 06-17-2014, 05:50 PM

OK. The RV-6 has been running like a champ. Last week my partner and I performed the GAMI Lean Test to see if any of our injectors needed to be re-sized. John Paul from GAMI called back after he analyzed our data and said, "Don't touch a thing. You are exactly where you want to be." Great news or at least it was until yesterday.

Flew the airplane yesterday from Charlotte to Cincy to see a friend. We generally run the airplane LOP now with tremendous success and efficiency, so I settled into my normal leaning procedures during the climb and cruise. At cruise I noticed the number 3 EGT was higher than normal. Normally all EGT's are very close to each other. Not today. See pic Below:

Then I switched the engine monitor to Peak Mode and noticed I could not get the airplane to run anywhere near LOP as it normally does and observed these numbers. I can normally lean to about 50 LOP and 7.2-7.5 at altitudes above 10,000' See below:

Anyone have idea what's going on here? Clogged injector or fouled plug maybe? I performed a "mag check" on the dual EI system on the ground and in flight and all seemed normal.

rv7charlie · #2 06-17-2014, 06:33 PM

Intake air leak? How does it idle?

Clarkie · #3 06-17-2014, 06:40 PM

Idles just fine.

erich weaver · #4 06-17-2014, 06:52 PM

Your last pic seems to show the aberrant cylinder is a little LOP whle the others are quite ROP. Taking that at face value, suggests significantly lower fuel flow and clogged injector.

DanH · #5 06-17-2014, 07:46 PM

Quote:

Originally Posted by erich weaver

Your last pic seems to show the aberrant cylinder is a little LOP whle the others are quite ROP. Taking that at face value, suggests significantly lower fuel flow and clogged injector.

Yep.......

RV3bpilot · #6 06-17-2014, 07:51 PM

I'm with the other guy, plugged injector. I use a 10 micron filter purchased from aircraft spruce that does a great job of keeping my injectors clean. I have clogged up my filter but not the injectors, the filter is easy to clean and put back together. I hope you get it repaired before melt down!!!!

airguy · #7 06-18-2014, 07:58 AM

Plugged injector.

Clarkie · #8 06-22-2014, 03:08 PM

So.....Good news is the fuel injector looked fine and not clogged. Bad news is the cylinder head is cracked. Not happy.

Smilin' Jack · #9 06-22-2014, 08:06 PM

Tom,
You stated the cylinder was cracked where. You are really hauling with your RV6 what engine are you running Hp? When you start to run lean of Peak what % power are you running. I have tried lean of peak but generally start off at 65% ROP then go LOP and usually lose around 3% end up at about 62% LOP

I have had an injector plugged with a small piece of carbon and my engine was so rough I could not even do a satisfactory mag check. Mine was the #1 cylinder.

Hope your situation is not too bad on the engine cylinder
Jack

Clarkie · #10 06-22-2014, 08:24 PM

Jack,
I haven't seen the damage yet. I took the cowl and the plenum off and left it for the mechanic and left for an out of town event. I get home tomorrow and will report back.

We are running an ECI IO-360 with 10:1 pistons putting out 200 HP. Our cylinders are affected by the AD they issued a few years back, but was told that if we hadn't experienced such cracks within 400 hours, chances are we were good to go. They made it to 768TT.

The engine has been an incredible performer up to this point. Both my partner and I religiously follow the leaning procedures that Mike Busch and John Deakin write about so often. Generally we run about 65-67% at higher altitudes with WOT and lean within the parameters that both leaning gurus suggest.

More info to come tomorrow after I see the engine.