hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 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. Quote
hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 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. Quote
hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 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): 1 Quote
hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 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: Quote
hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 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.: Quote
hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 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. 1 Quote
hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 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. Quote
hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 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): 1 Quote
MikeOH Posted October 28, 2024 Report Posted October 28, 2024 By no means am I questioning your ability but you may be pushing the Coleal interpretation pretty far into the gray area. I assume you are going to record this in your engine log, as required. Have you considered how an IA at a future annual is going to react to this repair with only an owner's signature for the work? What is your plan if he balks? 1 Quote
hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 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 2 Quote
Andy95W Posted October 28, 2024 Report Posted October 28, 2024 Don- I thought your spring compression tool was effective, common sense, well thought-out, and inexpensive. Nice! Quote
hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 I had to buy a 3 ft piece of aluminum at Lowe’s - $30. Did the job! 1 Quote
hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 #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: 2 Quote
N201MKTurbo Posted October 28, 2024 Report Posted October 28, 2024 Did you track the push rods so they went back in the same place? It looks like you threw them both in the same bucket. Quote
Fly Boomer Posted October 28, 2024 Report Posted October 28, 2024 10 hours ago, hammdo said: 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. Love the spring compressor -- couldn't be simpler. 1 Quote
hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 1 hour ago, N201MKTurbo said: Did you track the push rods so they went back in the same place? It looks like you threw them both in the same bucket. Yes, marked them so I knew where they went… sharpe dot on the exhaust. Same with the rockers… -Don 1 Quote
hammdo Posted October 28, 2024 Author Report Posted October 28, 2024 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 1 Quote
hammdo Posted November 1, 2024 Author Report Posted November 1, 2024 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… Quote
hammdo Posted November 1, 2024 Author Report Posted November 1, 2024 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 2 Quote
hammdo Posted November 1, 2024 Author Report Posted November 1, 2024 To be complete, this is my engine log entry (unsigned here). Cylinder Drain Tubes on separate entry: Quote
hammdo Posted November 10, 2024 Author Report Posted November 10, 2024 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 1 Quote
hammdo Posted November 22, 2024 Author Report Posted November 22, 2024 Everything has gone great -- did some IFR approaches with low ceilings (400 ft). While doing some lubing, I realized the rudder and elevator controls need some love. I ordered some low time control rods from a 66 Mooney that look like new! My current ones look like this (below) so I think its time to have them updated. I'll see if Maxwell's have time -- wouldn't think it would take too long. I also purchases the dual elevator rods that are in the tail section. I'll have them replace the rudder heims and that should really get this in great shape. 1 Quote
Ragsf15e Posted November 22, 2024 Report Posted November 22, 2024 On 8/12/2024 at 8:23 AM, hammdo said: The Big Texan Restaurant was outstanding -- food, service, atmosphere -- really great place and a must stop on I40 in Amarillo. Everything was delicious -- jalapeno coins were awesome in their ranch dressing: Ha! I just saw that you went to the Big Texan! We use to go there all the time when I was teaching USAF pilot training. Amarillo is a good dinner stop on cross country. If you call the restaurant from the fbo, they’ll come pick you up in a huge black limo (~60s era?) with real Texas longhorns across the entire width of the front of the hood! 3 Quote
hammdo Posted November 25, 2024 Author Report Posted November 25, 2024 Looks like the oil leak is solved, did a flight today and the residual oil is pretty much gone. Doing oil change now to clear out the dye. Noticed my electric step stopped going up/down though - it’s attached to the beacon and that is still working. Sent a note to @takair about it. Will report back on it. Gonna give Maxwells a call on the control rods to see about changing those out. Never ending maintenance it seems… -Don 1 Quote
hammdo Posted November 26, 2024 Author Report Posted November 26, 2024 Well, started on oil change, found the quick drain won’t go up anymore. Tried to remove it and someone in the past seal those drain plugs forever. I tried removing the plug on the pilots side and BROKE my cheap wrench! So, had to resort to using the electric oil drain pump and that did the job. I’m not about to drop the sump - I have a feeling the sump would need to be replace since these damn things are in there for good. Not spending 3k to 4k on a new one — didn’t find a used one either. Electric oil drain pump worked just fine and a drip of oil occasionally from the quick drain. Would love to know who seal the drains shut… Anyway, change is done, filter on, run up with no leaks. Didn’t see the problem yet on the step - looked for the fuse but didn’t see one. May have to have the shop look at that during annual. -Don Quote
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