hammdo

W91 - Smith Mountain? I believe they too rent hangers… -Don

Same response when they deferred it… -Don

Hell of a racer too… -Don

Did another flight today in the pattern. Post flight check was great. I only see the residual oil left so cleaned it up. I’ll probably have to do this a bit more as it was really a mess before the fix. I’ll fly it one more time in the pattern then change the oil again. As of now, running great and I’m slowly getting the oil leaks taken care of… -Don

This should work ;o) -Don

Congratulations! Well done! -Don

To be complete, this is my engine log entry (unsigned here). Cylinder Drain Tubes on separate entry:

Did the run up today, then did a high speed taxi. Checked things out and did a full flight in the pattern -- flew and ran great! No more leaking oil on the top after 1.5 hours of run time! She looks pretty good -- did see some residual oil from the leak but at least its not all over the place anymore (before and after the run). I'll do another cleaning to get as much of the old oil out but this looks to have taken care of about 90% of the leaks (oil cooler fittings and the quick drain need updates). Overall, really turned out great and boy this engine runs well... -Don

Decided to do cylinders #1 and #3 -- pretty straight forward but, on #3 the exhaust valve spring has an ash-like coating on it - I didn't remove it but I'm wondering if this is what Sal's was eluding to about cam guard (#1 has the silicone gasket). Also replace the #1 cylinder drain tube…

Initial run up today went well, did an extended run with the cowling off so I could look for leaks. Warmed her up, did about 1500 RPMs, ran smooth! I’ll button her up and do a full run up and maintenance flight next. The left side had the leaks so I’ll stop where I’m at to make sure all is good. I fly her in the pattern for a couple of days, then probably change the oil as it’s right at that time again… -Don

Yes, marked them so I knew where they went… sharpe dot on the exhaust. Same with the rockers… -Don

#2 cylinder updated -- same steps -- note the spring clamp is oriented differently (just to be complete). Replaced the dented tube on the exhaust side since it was clearly leaking at the dent:

I had to buy a 3 ft piece of aluminum at Lowe’s - $30. Did the job!

I document it completely for sure. I did check on this and from what I saw, replacing was ok. If an IA balks, I’ll let them re-do it. It really is not a complex process. Removing a mag, cylinder, yeah, not gonna do that without AP/IA. Pushing Coleal? If this was a complex job (which to me this wasn’t and well within my skill set), I’d agree. I guess time will tell… The reason I documented it was to show I’m working with what I can tell is in the spirit of Coleal. Simple maintenance task that are not complex. -Don

Before I started, I got everything ready AND put rubber mats down -- just in case I dropped anything (don't want a broken spark plug -- those fine wires are expensive):

DId number 2 cylinder the same way (it had a big dent in the tube). I also inspected #4 and the shroud for the intake side had a bad spot right where it entered the cylinder. While I was at it, I replace the #4 cylinder drain tube since it had chafing on the aluminum tube. I did put chafing tape on that area also. Pics of #2 and #4 cylinder completed and ready for a run up. I plan on doing #1 and #3 too. Just taking my time and not rushing things ;o) I know these are good tubes, new seals with new spring clamps. I also know the spark plug has new washer too. Not a bad job and after reviewing Coleal, this is not a complex disassembly and simple to do with the right set of tool. I didn't do this because it was cheaper (it certainly was not since did buy all those tools -- including the calibrated torque wrenches) but since I felt I had the necessary skill set, I did it. I did use the assembly lube on all contact areas, push rods, and rocker arms.

Next put the pushrods in and then assembled the rocker arms. I had to make a spring compressor to allow me to 'tweak' the rocker arm shaft so it would glide in -- you know, the lifters were still pumped up and I didn't want to even remove those. Once that was done, and the rocker arms were back in place, I then re-installed the Thrust Buttons and install the new valve cover gasket. Lycoming has and SI that details the torque spec and sequence. After that, I reinstalled the spark plug with a new washer, torqued using the calibrated torque wrench (30-35 ft lbs), then installed the lead. THE LEAD required me to use a 7/16 wrench to hold the lead from moving while I used a 3/4 wrench to tighten the lead down on the spark plug. THIS IS A MUST to prevent the lead 'cigarette butt' from breaking.

Using a new spring clamp, lock plate, and nut, assembled and torqued using a calibrated torque wrench to 96 inch lbs. I then had to tighten the nut a bit more so the lock plate would sit flush -- you can see that in the pic. I then used a channel lock to crimp the lock plate down.:

Next, I clean everything, made a 85% 50 wt mineral oil, 15% STP mix per Lycoming SI instructions for rockers. Once I did that, setup the new push rod shrouds (I did paint them with self etching primer and HI temp engine gray paint), setup the seals using the assembly lube mix, and install the tubes - pushing until I felt the 'pop' once its locked in. I used a screwdriver handle that was the same size as the tube to confirm they were properly seated:

I then removed the spring clamp, lock plate and nut -- keeping them in the same orientation. Then I removed each shroud and put the appropriate pushrod to keep track of the push rods (shown above):

Once that was done, I removed the rocker arms and push rods -- noting the side they belonged to and organized them. I noted the orientation of the pushrod shroud, spring clamp, lock plate, and nut. This is important to make it easier to re-assemble. I organized the shrouds with the pushrods so I would know where they went. I did 1 cylinder at a time to keep things simple.

Well, I decided to go ahead and do the pushrod shrouds. This is a multi-post set so I'll do each in steps so the pics flow. After reviewing all the SIs and Lycoming maintenance manual, I decided its really a pretty simple and not complex process. So I started on #4 and removed the rocker cover. I then removed the spark plug, got the cylinder on TDC, verified the intake/exhaust were off the lobs, then I slid the rocker arm shaft side to side to remove the Thrust Buttons from both sides of the rocker shaft -- that was VERY easy to do.

Extra plug or put a fine wire plug in the lower cylinder spark plug location. id try that after ring flush… -Don

Maybe try the cylinder ring flush first as Mr. Busch suggests…. -Don

Keep the inspection panels! -Don