The first thing I would do is clean the web real well and look very carefully for cracks. The earlier ones are a lot lighter than the later ones and tend to break for it.
Can a later, heavy, web be used in an earlier block that had a lighter one? Are the webs in general interchangeable or they have to go with the block they were made for?
I pulled the web on mine with a steering wheel puller/general bearing puller. Put it on the protected nose of the crank, then screw bolts through the puller, and into the holes on the web. They are meant for it. Honestly, you can pull that engine with a set of: sockets, allen wrenches, box wrenches, and screwdrivers. Possibly even with just the stuff in the toolkit.
Yes, you can. But somewhere in the back of my mind is something about the oil passages that don't line up. I'll check tonite how old and new compare. Paul.
Interesting area we are getting into. I have several webs. I think I have all older ones. Not sure I haven't done much with this stuff in a year but I'm supposed to be building an r100 engine. I have found that the web is an easy part to pull. But the problem is the crank gear in front of it. Always protect the crank tip with a button or something. It may be a good idea to pull that bearing first, I usually have pulled it with the gear. I've done several with Snap On and OTC pullers. I now have a BMW shop puller but it may not work at all because it's damaged. I think on reassembly it would be a good idea to heat the block and chill the web. Which brings us back to Anton's idea that this whole mess can be easier handled with the engine out of the frame. He would know, he does this stuff daily.
Anton isn't the only one here that works on them every day offering some great advise. Sure you can take the engine out but you don't have to in order to do the job perfectly and that includes heating the case up in the frame and going over the rest of the engine in the frame to give it some love. Personally, the only engine repair that I can think of that can be done better with the engine out of the frame is the rear main bearing. I am just trying to help the OP.
Okay, here goes on the matter of the front bearing webs, if the OP doesn't mind, that is. Old vs new; Note the newer has more 'meat' and a different tensioner for the chain, plunger vs spring, as seen on the right on the right web. View at the side of the web, the old has 2 holes, one for the oil to enter, and one to feed the camshaft bearing, where the new has a gallery to accommodate both. How that lines up with the engine casing can be seen on the next pic. The scribed line at 4 o'clock is the oil feed from the pump. (in) The scribed line at 6 o'clock is the oil feed to the camshaft. (old) The line next to it is the newer oil feed to the cam (new) The arc is the area the gallery in the new web covers. The lines at 10 and 02 o'clock is where the oil feeds to the rockers, same for both old and new. Last pic on this subject shows the holes in a newer casing, oil in, connection to the filter cavity (rectangular) and feed to the cam. And to stay on topic, a pic from the pin in question, fitted and peened over. Paul.
If the OP is a member of ABC, drop Oak a line. I "think" he suggests tapping that hole and threading in an allen bolt with Locktite. I don't remember the size or the exact method. It should be in the ABC news letter from the last several months. Anyway, the advantages are you can remove it later, it won't fall out and your bearing will be securely in place.
Plse explain the difference. I know peened over, but staked I don't know the Dutch translation. As far as I can see from this, the hole isn't running the length of the part, but a little off-set. The pin is inserted from the bearing side and locked by a square pushed in. This better? Here you can see 1/2-2/3 of the pin off-set through the hole and the square pressing. Paul.
Method of retaining pin I think is an issue and what brought us this far so far. I like the idea of a threaded bolt. As far as interchangeability of the two style webs, it looks like the oil will not be an issue. I'm not sure I have that right, but is that what the examples tell? However the timing chain tensioner was mentioned. The old style fits a double row chain and the new style fits a single row chain. So at first glance I think they are not interchangeable with out a few, maybe more, changes. Unless those chain tensioners will work on either chain?
I wish you had comparative photos of the peen bosses too. The later ones are a lot beefier in that area too. I am pretty sure you can crack the web while peening in the pin. I have seen a couple cracked right there although I am not sure that I didn't crack one of them myself.
Your wish is my command. The last pic is from the later web, here's one from the earlier one, /5-/6 me thinks. Paul.
There are beefier duplex webs. By mid /7 for sure. I think they did it in a couple of stages. The old pin will work fine. You use the same hole in the web. It's the bearing that needs to be drilled and reamed. I recommend having someone with experience do it. It's a tricky job to do it right no matter which way it is done.
After reading your description of staking I don't understand how that pin is staked? I use to work on prewar US aircraft a lot and I have never seen or heard of any aviation threads staked. For a situation like I think you are describing I have seen different standardized threads used that have an interference thread. The adjuster studs and lock nuts on Travel Air interplane struts comes to mind as do the adjuster lock nuts on a couple of parasol wing struts.
And as far as interchangeability goes the timing chain tensioners will both work on either type chain? I'm putting a question mark there because I haven't got one to look at but nobody said I couldn't so I guess I'll have to try and compare them myself, if this ever comes up. If I remember the directions for installing the pins. The hole for the pin is drilled in several steps so the pin is an interference fit and the Aluminum of the web is crushed with a punch, the factory used a square punch, I think a small chisel will work also. The "stake" is to prevent the pin falling out. If there is not enough metal for this in the old place the pin was then put it in another place. I've never done this but think that would be the way. A small bolt held in with Red Locktight might be better but I'll wait for some expert to tell me how that works, how to properly install it. I don't see much problem with the pin. The OP's pin was not properly staked at the factory so it fell out. The problem when rebuilding the lower end of the engines is selecting the proper bearings for the size crank you have.
