More surprises!

Curiouser and curiouser! I spent a fair amount of time during disassembly taking measurements and writing things down, and then promptly forgot to worry about any of those numbers. When I was sold this engine, it was sold to me as a 2180. There was some mystery behind its history, but I didn't think too much of it. However, as I was ordering parts today, I realized that the numbers didn't match up.... specifically, the cylinder and crank numbers. 

A Volkswagen 2180 engine begins life with around 2/3 that displacement, and then a bit of machine work is down. The crankshaft, which comes stock with a stroke of 69mm, is replaced with a crank with a stroke of 82mm. In addition, the cylinders and pistons, originally in the 85-90mm bore range, are replaced with 92mm sets, which gives the final displacement of 2180cc.

My Volkswagen "2180" engine no doubt had similar beginnings, but the end result is a bit different - the pistons are not 92mm, but 94mm. The crank stroke, likewise, instead of 82mm, is 78mm. The engine I'm working on has, in fact, a displacement of approximately 2165.

What does that mean? I'm not sure. Obviously the parts for it are different. As far as power and reliability, those depend a lot more on quality of workmanship than they do on any other factor. Bottom line, I *may* have a little more torque, or I *may* not, and at the end of the day it's still up to me to build a solid engine. 

This does cause some complications, though. The main one I've run into so far is that nobody sells cylinders for a 78mm stroke... only 69mm and 82mm. That being said, some folks sell the 82's as "78-84mm," and don't give any other dimensions. There are three possibilities, as I see them (in order of most preferable to least preferable from my point of view):

1. The cylinders are short enough for 78mm stroke, and you add shims to use them for longer strokes

2. The cylinders are long enough for 84mm stroke, and you cut them down on a metal lathe if you need shorter cylinders

3. The cylinders are somewhere in the middle, and we don't really expect you to worry about compression ratio that much.

I'll know better once they show up and I can measure them. One way or another I'll get this engine built.... but if I have to custom cut each cylinder, it'll probably cause me to wait a little longer before the next rebuild.

On a more normal note, I finally got my crankshaft ready to send out for NDT (Non-Destructive Testing). Here's the key in the slot:

Partway removed:

All the way out:

I hope to spend some time this weekend cleaning the parts I intend to reuse... we'll see if I can pull myself away from this guy long enough to get any work done.

Slow progress, but promising results!

A few months ago, my wife and I relocated to Rochester, NY for work, and to be closer to her family.

A small part of my new job is machining odd parts on a Tormach 1100, a 2.5 axis CNC mill. As a result, I'm now able to make *much* nicer and more complex parts than I could on my drill press in my shop back in PA. Which is really handy, since I ruined a couple of custom pieces taking this engine apart.

This is a two-piece housing that holds an oil seal. All of the information I could gather said that this should be attached in a way that prying and application of heat would allow its removal. All of that information was incorrect, as it turns out. Several #6 screws, hidden by RTV sealant and covered with paint, held this assembly on. I managed to bend it during my first failed attempt at removal, but even worse, I scraped the sealing face pretty bad with the screwdriver I was using to pry it off. As a result, I needed to replace both pieces.... and it just so happens I now have the tools to do so.

I didn't take a lot of pictures, but here's a shot of an aluminum blank next to one of the (almost) finished pieces:

I think the originals were turned on a lathe, based on the finish on the old parts vs the finish on the new parts. (Admittedly, I am not what most would call a competent machinist, so maybe I just failed to produce a quality part.) However, I think the new pieces will work out just fine.

According to the book I'm reading, "How to Rebuild your Volkswagen Aircooled Engine," Tom Wilson says the best way to clean the aluminum/magnesium engine case is with regular old soap.... with phosphate. Probably wasn't hard to come by when the book was written, but now it seems nobody sells it. I'm going to try regular old soap without phosphate, and see what happens. I'll be taking my crankshaft in next week to have it magnafluxed, and if it passes I'll be placing my big order for engine parts. My hope is that the engine will go back together pretty quickly, since there was no apparent damage and it ran ok before. 

As explanation for my apparent lack of significant progress, allow me to placate you with a picture of my son, who was born a few weeks ago, and has been eating up all of my time. Strangely, I don't mind....

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: https://www.motorencenter.de/fileadmin/usercontent/King-Engine-Bearings-catalog-2015_2016.pdf )

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....

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.

Engine DISassembly (Part 3)

I've been stuck trying to find the right tools for the last week or so, and then trying to find the time, but I finally made some progress. The pictures below show a collar assembly on the front of the motor, behind the prop hub. Apparently this setup is an anomaly - no one I spoke with was able to identify it. There are 4 screws that hold the front collar onto the back collar, which has one screw into each side of the case. Once I got the right size hex key, these came off and the case came apart.

These two collars house an oil seal around the crank shaft where it exits the case. My first inclination is to replace the seal, but I'm not sure what kind of damage I might do removing the prop hub. I'll have to think about it.

Once the case was split, I pulled all the cam followers and labelled them so I could replace them in the same locations. I'll be taking a lot of pictures once I've cleaned things up, but the camshaft looks like it's in great shape, so that and the followers will probably stay.

The inside of the engine wasn't as pretty a machining job as I'd expected, but everything turned nice and smooth when it was all together, so I'm not too worried about it. I haven't found a reason for the fine metal shavings yet, which makes me uneasy. 

This is where I left it. There are only a couple of things left to do on the case before it can be cleaned up and inspected, and I don't expect the crankshaft assembly will be difficult to take apart. After that I can begin blueprinting, clean and inspect, order my parts, and put this thing back together.

Engine DISassembly (Part 2)

Not much progress today, but I got a little further. I keep running into bolts that I don't have wrenches for, although hopefully that will stop soon. The main thing I accomplished today was setting up a table to work on, covered in plastic, and transferring the engine block from the stand to my new "workbench."

I got the pistons out, which ended up being easy enough... the Teflon buttons really were just floating in there, but I needed something sharp to stab the sides of the buttons to get enough grip to remove them. I forgot to take pictures of them tonight, but when I get into working on the cylinders I'll be spending about a paragraph on how crummy those buttons are.

Removed cylinders yesterday, but they're all laid out in order here. You can see the lower right cylinder has a lot of corrosion on the outside of it - the other three cylinders aren't corroded much at all. I think the corroded cylinder was a quick replacement to avoid a more serious rebuild earlier in this engine's life.

Another disappointing discovery when I removed the accessory case that covers the flywheel - the teeth are chipped pretty bad on about a quarter of the flywheel. Not messing around with that - I'll have to replace it.... unless they sell just the ring gear for it. I'll look into that...

I also removed the valve springs, and while those all seem to be in good shape, I did notice that the same cylinder with lots of corrosion also has mismatching valves.... the valve on the far left below has almost no carbon deposited, not to mention is shaped different. I'll have to make a decision on whether or not that is an issue/will bother me enough to get new valves.

And here's the part where I don't have a big enough wrench - or rather, big enough socket. Not sure a wrench would be really effective, since this is recessed inside the flywheel.

Tomorrow I'll pick up some more specialty sockets, and hopefully make some more progress on tearing this thing apart. My goal is to have a semi-final list of parts to order by the end of the coming weekend, as I suspect some of the parts will take some time to acquire... especially if I wait until the holiday season.

Engine DISassembly (Part One)

After a bit of a hiatus, I began tearing down the engine I intend to hang on the front of the plane. I'll be using a 2180 Volkswagen engine, originally built for aircraft use by Hapi a number of years ago. When I received the engine, it was mostly assembled, but I wanted to tear it down, blueprint everything, and rebuild it myself so I know it's done right. Besides, it's hard to powder coat an engine block with stuff attached. So today I finally started yanking stuff off.

Engine on the stand, ready for disassembly:

First I pulled the intake manifolds and spark plugs. I'm working on this engine away from home, so I lack most of my tools and all the helpful things like oil drain pans... Therefore, I used an empty lemonade bottle to catch the old oil. Seemed to work.

I pulled the valve covers, then the valve train. Sure looks a lot simpler than any other engine I've taken apart.

Next step was to pull the head, which came off pretty easily, along with one of the cylinders. The other cylinder wasn't much trouble.

The pushrods and pushrod tubes fell right out as well, and I hung onto those for referencing when I reassemble. I'll probably replace them, along with a good deal of other hardware inside.

The left head valve train was shimmed about .122 off of the head.

The right side wasn't any more difficult than the left. Valve train shimmed .088 on the right side.

I'd have liked to do more, but a little research is in order. The pistons are held on by a large pin, and that pin is usually captured by E-clips or similar devices. Whoever assembled this engine most recently used Teflon blocks that ride against the cylinder wall instead. Nice idea in theory, but if they ever wear down, there wouldn't be anything holding the piston pin in place... which would mean a catastrophic failure. I also noticed that one of the Teflon "buttons" had picked up some debris and scored the cylinder wall with it... another thing that wouldn't happen with the right hardware. I'll have to take some measurements and decide whether I want to hone that cylinder or replace it.

This is where I left off today.

You can see the Teflon "buttons" in the picture below - they're the white circles on the sides of the pistons. I have no idea how to remove these, unless they're to be pressed out with the piston pins. Time for research.