Dialed In

1) I put a new PCU on last year and had the same symptoms. Prop was new in 2006 and has 1500hrs on it. I got ahold of the manufacturer APS and they told me to send it back to them. They polished a spool and sent it back to me. It now works as expected. If you need contact info let me know. 2) Check and make sure your oil cooler lines are routed to the correct ports on your filter head. I also rebuilt my engine this year with oversight. OAT 60 degrees @ 6500ft yesterday 68%power 100 degrees ROP and 206 degree oil temp. 35 hours on engine so far. Oil cooler should be warm if your oil temp is over 190 at shut down.

Make sure you blow out all of the contact cleaner before your final assembly or it will eat the weather pack.

@AerostarDriver what did you decide to do on this repair and how did it turn out?

@Steve Dawson any headway yet?

These are what mine looked like before I replaced them, 1965 e.

I'm just trying to get a more complete picture. An inflight mag check would tell you that both ignition systems are firing under load. A runup mag check might be good but when the pressures and temperatures are higher in flight a maginal plug may be not firing. I'm pretty green on aircraft piston engines but I do know that when running on one plug the EGT's for that cylinder go way high. The engine will run like this in cruise but I have heard under full power it can be detrimental. Also if the plug is not firing it will accumulate carbon and foul. I would perform a compression check on the cylinder to see if there is air leaking anywhere it should not be. Don't assume the cylinder is good just because it was just gone through. Turbo's don't produce positive pressure all of the time, just when the drive pressure from the exhaust is greater than the suction from the intake. It is common to have a vacuum in the intake system at idle. How much is your oil usage in quarts/hr? Is everything else satisfactory? Good power? If the only complaint is fouling a plug it could be a bad plug, bad wire, or something wrong with the mag.

Have you done a bore scope inspection and compression test on the number one cylinder since overhaul? What do you have for engine monitoring? How hot is the number one cylinder vs others? Have you performed an inflight mag check? When do you find the fouled plug? At the next run up or after the flight it runs rough?

I had a terrible experience with west coast governor last year when I purchased my new pcu-5000. I will never do business with them again. The guys that manufacture the pcu, APS, however are top notch and have fantastic service. Find someone other then west coast to buy it from though.

https://www.flywildblue.com/airplane-for-sale/1967-piper-arrow/n3962t @N2391Y I have a 1965 m20E and love it. I have not read all the responses however my hanger neighbor is selling this arrow, it is well sorted and he takes very good care of it. If I were in the market this one would be towards the top of my list.

It would have likely been cheaper to just move the tach pickup to the other mag instead of using the signal converter. I suspect when you kill the surefly mag the signal also dies so you get no tach reading. I just went through this install and elected to move my tach pickup to the right mag instead of using a signal converter.

I’ve never heated the tail section of my E and have yet to have had an issue, I even have a 5 year old wet gill battery. I typically plug the oil pan heater in over night and then heat the cabin for 1/2-1 hour before the flight. It’s not uncommon for us to have 2-3 weeks of highs in the -20 Fahrenheit during winter and I fly a couple hours every week. I did have the gyro serviced three years ago, it was the first time the oil had been changed in it since 1965.

So I have my engine assembled and hung on the plane, I have done all my ground runs and everything seems normal. During the ground runs we were about 60 degrees outside and after the ground run we went through an annual. Now the weather has changed and we are 20-30 degrees Fahrenheit for a high and around 10 for a low. I plan on following lycoming’s recommendations on breaking in an engine. My IA is fine with doing the break in when it’s chilly like this since the DA will be lower and the cooling will be better. I should mention he worked on aircraft in Alaska for a few years so he is familiar with the cold and breaking in engines. I’m not worried about the cold starts as the engine and oil will be at 70 degrees. I’m just curious what others opinions are on breaking in an engine when it’s cold outside. I’m well aware of ring flutter and cylinder cooling in the decent. Thanks, -Chase

What were the hours and how long ago (calander) was the overhaul preformed?

You can see the weep hole on my manifold pressure line at the top by a small dab of silicone if you zoom in. I think most are further down by the intake.

Do you have a mechanical gauge or digital?