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Video Sticky Valve and Reaming Cyl 4 on 390 Angle Valve

M

Micke

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Below link to my youtube video showing the reaming of the No 4 exhaust valve on my Lycoming 390 Thunderbolt. I had no prior experience in this area but it is very doable. Study vansairforce posts, kitplane articles, youtube videos. Follow the steps in the applicable engine maintenance manual. Pay attention to parts like gaskets and washers that should be replaced. The parts numbers in the Lycoming parts manual can be used when ordering parts from Spruce. Cyl 4 runs considerably cooler (CHT and EGT) than the other cylinders which seems to support Mike Busch's view. 330 hours on engine.


Mike
 
Micke said:
Below link to my youtube video showing the reaming of the No 4 exhaust valve on my Lycoming 390 Thunderbolt. I had no prior experience in this area but it is very doable. Study vansairforce posts, kitplane articles, youtube videos. Follow the steps in the applicable engine maintenance manual. Pay attention to parts like gaskets and washers that should be replaced. The parts numbers in the Lycoming parts manual can be used when ordering parts from Spruce. Cyl 4 runs considerably cooler (CHT and EGT) than the other cylinders which seems to support Mike Busch's view. 330 hours on engine.


Mike
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Very nicely done. Most seem to have the issue with their hottest CHT cylinder. What oil are you using? Did you see any morning sickness in your EGT's?
 
dmattmul said:
Very nicely done. Most seem to have the issue with their hottest CHT cylinder. What oil are you using? Did you see any morning sickness in your EGT's?
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The builder/seller used Phillips Victory oil so I stayed with that but added Camguard. Oil changes used to be at 50 hours intervals but I think I will go for 25 hours. Plane has a Raven air/oil separator.
I had two short morning roughnesses on coller mornings and the third time Iost EGT for one minute.
 
Micke said:
Below link to my youtube video showing the reaming of the No 4 exhaust valve on my Lycoming 390 Thunderbolt. I had no prior experience in this area but it is very doable. Study vansairforce posts, kitplane articles, youtube videos. Follow the steps in the applicable engine maintenance manual. Pay attention to parts like gaskets and washers that should be replaced. The parts numbers in the Lycoming parts manual can be used when ordering parts from Spruce. Cyl 4 runs considerably cooler (CHT and EGT) than the other cylinders which seems to support Mike Busch's view. 330 hours on engine.


Mike
Click to expand...
what oil pressure do you typically see in cruise?
 
Do you have a link for that tool to push the spring in? I made one and it did the job but it is as ugly as hell.
 
Micke said:
The builder/seller used Phillips Victory oil so I stayed with that but added Camguard. Oil changes used to be at 50 hours intervals but I think I will go for 25 hours. Plane has a Raven air/oil separator.
I had two short morning roughnesses on coller mornings and the third time Iost EGT for one minute.
Click to expand...
Thanks, I assume you are aware that Victory already contains an antiscuff/antiwear additive (LW-16702) but Camguard can't hurt. For some reason the use of Phillips oil seems to have a higher incidence of sticking valves in the IO390. Maybe not statistical but "seems" so. I used Phillips Victory for a couple hundred hours (No Camguard) but switched to a multiweight Aeroshell product as the Phillips would get fairly dark quickly and the Aeroshell at least looks cleaner longer. I also change my oil every 25 hours and filter every 50 since new and now have over 700 trouble free hours. (Hopefully luck will continue)

Again, thanks and welcome !
 
Thanks for taking time to video and post your experience. At about 400 hours, I recently decided to ream all the exhaust valve guides on my -14A. I didn’t see the amount of build up you saw, but cylinders 2 and 3 had some.

For anyone working on cylinder 4, I found that I could push the rocker arm pin out without cutting a hole in the rear baffling. Instead, I simply unscrewed three screws on the rear baffling that allowed me to push the baffling out of the way.
 
I also used a Valve Wizard when I did #4 on my O-360. It is a funny looking tool, and not cheap, but it makes the job REALLY easy.
 
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