Saturday, January 21, 2017

Those bearings fit a what!?

I began searching for clues as to what bearing replaced the usual #4 on this engine. First, I checked the bearing, and was able to find some numbers: 7D03 and 7D02, as well as STD (abbreviation of Standard, meaning this bearing fits new engine cases for the engine it's designed for, as opposed to bearings for engines that are line bored larger during overhaul.) So I started with that. Unfortunately, none of the parts stores I got in touch with were able to cross-reference that number to any of their bearing sets. Since the company that converted my engine for aircraft use is no longer in business, I couldn't contact them for help. I reached out to other folks who are part of the homebuilt and vw-for-aircraft community, but they were unable to provide any information. So I took some measurements and called the parts stores to see if they could match up a bearing set to dimensions. NONE of the parts stores I talked to had any way of doing that! At this point, I was at a loss. I looked into setting up the engine to run with the prop on the flywheel end instead of the pulley end, but my engine case was modified so I'd need a special bearing anyway, and without a way to order bearings by dimension, I was up a creek. Eventually, through several long nights exploring deep into the heart of the internet, I found a very large PDF from a company called King that links bearings to their vehicles AND THEIR DIMENSIONS, and was able to find fairly quickly with a search function *exactly* what I was after. (A direct link to the catalog is here: )

Once armed with a part number, I was able to cross reference that number and get a Federal Mogul number, which Rock Auto had available for about 15 bucks. Upon arrival, I checked all the dimensions, and I'm quite convinced that this is the bearing used in my engine. What does it fit? Why, a 1968 Nissan 520 Pickup, of course.

New bearing below, along with old one for comparison:

With that mystery solved, I'm cleaning my crankcase and crankshaft so I can have them tested for cracks. I don't expect to have that done this week, as I'm coming down with something nasty and don't feel like doing *anything.* Baby steps are still progress....

Saturday, January 7, 2017

Engine DISassembly (Part 4)

Between the holidays and lacking the proper tools half the time, it took me until now to finish gearing the engine apart. Mainly, the prop hub and crank gears were my main difficulties.  The prop hub I removed with the aid of a 3 jaw puller and two 4-foot extensions. One was a piece of angle iron drilled to fit the prop hub holes to keep the crankshaft from turning, the other was a 1" iron tube around a breaker bar.

Once the prop hub was off, the next task was removing the cam and distributor gears. I machined a couple of pieces of aluminum and made a makeshift puller for those. Forgot to take  a picture of that, but it worked. This picture shows the crank before the gears were removed.

The next two pictures are the main bearings, which I'm having difficulty locating replacements for. It seems the 4th bearing (bottom of first pic, right-most in second) is something different than normal, and I'm not sure where to look to find one that matches.

Once I have that figured out, I'll start ordering parts and cleaning things up for reassembly.