One thing I did forget to mention is that we also removed all of the rocker box covers (also known as valve covers). The Navalized versions of the R-3350-26WD have a manifold drain system to assist in draining oil from the lower cylinders (The Navy had Wright install them so that the carrier decks wouldn't be quite so oily...or so I'm told). It's kind of a cantakerous little item to remove and install, but it does wonders for how clean the engine runs. On the 3350 installations that are on most of the Sea Furies out there, that manifold drain system has been modified to include a scavenge tank and electric pump, which pumps the oil from the lower cylinders, back up into the oil tank (when the engine is not running). You won't believe how clean you can get these ol' "dirty-three-filthys" to run.
So anyway, back to the pushrod tube resealing job. Normally, I would just go around the engine in the numerical order of the cylinders (1,2,3, etc.), and some folks go around in it's firing order (1,12,5, and so on). It's just a matter of personal technique really. On this particular job, I chose to start with all of the front cylinders in hopes that we could get the front end finished up before I had to leave. (At the time, Dave was still nervous about reinstalling the prop without me there.)
I started with #18 cylinder (it just happened to be on the side of the airplane I was working on), but forgot to take pictures. So, here is how it goes while working on #16 cylinder.....
First, you look at what you've just gotten yourself into and say a few "choice words" about how you know your hands are going to feel at the end of the day. Notice that we had already removed all of the hold down nuts and washers for the lifter body housings (the studs sticking up with no hardware on them...a little tough to see due to the camera not focusing on what I wanted.
).......
Okay, so the
real first step is to insure that you have the cylinder on top dead center (the intake and exhaust valves should be closed). I'm sure there are several different sequences you can do the next few steps in, but here's how I attack it....
Remove all safety wire and loosen the lower pushrod tube gland nuts, but just break them loose. You really don't want to see more than one thread showing beneath the nut. You need this assembly to be as compact as possible for the removal in a later step....
Then you pull the lifter housing (with gland nut still attached) up the pushrod tube. It'll only go so far, but should clear the studs. If not, then you've got the gland nut too loose. Sometimes you need to use a little screwdriver or similar as leverage to help slide the housings up.....
Then you can loosen (all the way) the upper pushrod tube gland nut....
Once that's done, you need to loosen the pinch bolt securing the rocker arm adjustment screw, followed by backing the adjustment screw off as far as it will go (a modern day dzus tool fits the adjustment screw perfectly).....
Now comes the tricky part where a little technique is required. The lifter is of the "hydraulic-roller" type, and although we won't be removing the lifter all the way, the guts will be coming out of it. Unlike on most cars, the lifters on this engine have no retaining springs for the guts. The pushrod does all of the retaining. Sooooo, what you need to do to remove the pushrod is to pick up on the rocker arm with your fingers and hold it (there will be a slight amount of spring tension)....
Then you place your screwdriver (or other smooth, flat surface) on top of the lifter to hold it down (compressing the spring).....
You should then have adequate clearance to slide the pushrod (and pushrod tube) off to the side for now.......
Then remove the lifter cup and spring from the lifter (on the lower cylinders, this step is taken care of automatically
).....
It's important to get the first pushrod tube loose and set it to the outboard side of it's lifter to start with, in order to make room for the removal of the other pushrod tube. I've yet to figure a way out how to do one at a time. Once both pushrods and tubes are loose, you can remove them from the engine.....
This is how the assembly should look after removed, followed by the order of how the seals are stacked once you remove the lifter housing from the tube......
Then after cleaning the parts up and polishing the ends of the pushrod tubes (they sometimes become out of round due to over tightening), you lubricate the new seals with Dow Corning #4 (DC-4), and install them on the tubes, followed by the housing.....
The suckiest, most hand-torturing part of this job has to be the removal of the old lifter housing gaskets that are inevitibly left on the engine. It took me 45 minutes just to scrape the two gaskets off for this one cylinder. Fortunately, the part the gasket was stuck to was steel, so even though you must be careful not to gouge the metal, it's not as crucial as an aluminum part would be. Once you have the part(s) nice and clean, you put a thin coating of EZ-Turn (the old Fuel Lube replacement) on the gaskets and slide them into place.....
Make sure you put the right pushrod back in the right pushrod tube. I always mark the pushrods when they come out of the engine......
Then reinstall the lifter spring and cup, and hold them down with the screwdriver so that the pushrod can go back in place. (Notice in the first and third pictures here, how I had already installed the other pushrod tube and set it aside. Otherwise it won't go back in place if you've already installed one tube).....
Once both pushrods are in place, slide the housings onto their studs. Install new hardware and torque as required.......
Then you to to the UPPER gland nut and tighten it first. It torques to 400 inch pounds........
Then you tighten the lower gland nuts (forgot to take a picture of this step). These torque to 230 inch pounds.
Safety wiring the gland nuts is next. I know most of you already know how to do safety wire, but I thought I'd go ahead and show this process step by step as well, since these gland nuts can tend to be a bit tricky. The first step is to make a nice little hook on the end of the wire. (Sorry if the pictures are poor. It's kind of tough to get these little cameras to focus on what you want sometimes).....
Then you manuever the safety wire through the proper hole in the gland nut.......
Pull the two halves of wire to together and determine the right length needed to make the twist with the safety wire pliers.......
Once the twist is made, then make another little hook in the end of the wire so that you can put it through the other gland nut.......
Pull the wire through and give it it's final twist.......
Cut the excess off and make a nice pig-tail. (These pictures really don't do this justice, but I'm sure y'all get the idea.).........
Oh, and do the same for the upper gland nuts as well.......
The last step for now is to screw the rocker arm adjustment screw down to where you have just a small amount of clearance (.015"-.020" is fine). You want the valves to still operate when rotating the engine when working on the other cylinders, but you don't want them so tight that you get anything in a bind. Oh, and FYI...the valve clearance on this engine is .010", which will be adjusted when after all of the pushrod tubes are done..........
So there you have it...one pair of pushrod tube seals & gaskets replaced. Only 34 more and you've completed the job.
I've got to get some work done on the B-24 right now, but I still have enough pictures for one more installment of the Skyraider adventure later.
Gary
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