610 engine rebuild and lift/tilt control valve fix up.

[alchemysa]

The engine is finally out of the Bobcat 610. I had to remove it with the drive sheave still attached. What a job that was! Lots of other bits had to be removed including the left side engine mount so I could rotate it enough to maneuver it out the back. With the donk out I was brave enough to apply sufficient heat to get the sheave off. It took a LOT of heat.
Anyway, a rebuild is in the works. You can see in the pic the terrible condition of pistons 2 and 4. Pistons 1 and 3 weren't as damaged but they were well and truly worn. This engine has obviously been rebuilt once before, many years ago. The pistons were already 20 thou oversize, so I have decided to go for resleeving and returning to standard size pistons. I shall post a few pics as i go if anyone is interested but it will take a while because I have to get parts from the U.S. (I think I'll be getting parts from Rock Creek Consulting). You can also see the 7 snapped head bolts. No way were they going to budge so eventually I just had to snap them. I'll have to drill them out now. I tried welding nuts to the studs but they just snapped off.
Under the engine was about 3 inches of almost rock hard oil and dirt. I'm glad I have cleaned it out now because some nasty rust was starting to develop in the channel below the engine mounts. Another couple of years and it might have eaten right through to the petrol tank.
As I have gone this far I figure I may as well tackle the control valves and try and stem some leaks. Anyone done this before? Is there a kit I can get for this? Do i have to get the parts from Bobcat or do I just get stock seals from any hydraulics place?

 

[6brnorma]

Amazing……..I can't count the number of people I have told that engine can not be removed without first removing the variable speed sheave.
Pictures are great…….I have gone completely to the frame a number of times, now is the time to correct anything that needs attention in that machine. If it were my machine, I would pull the wheels and give attention to maintenance required inside the chain case as well. All of your valve seals can be had at any good hydraulic shop and I would definitely service that valve at this time. That valve is no longer in production …….. spools are your biggest concern. I see some other things I will comment on later…….gotta get to work.

 

[alchemysa]

Amazing……..I can't count the number of people I have told that engine can not be removed without first removing the variable speed sheave.
Pictures are great…….I have gone completely to the frame a number of times, now is the time to correct anything that needs attention in that machine. If it were my machine, I would pull the wheels and give attention to maintenance required inside the chain case as well. All of your valve seals can be had at any good hydraulic shop and I would definitely service that valve at this time. That valve is no longer in production …….. spools are your biggest concern. I see some other things I will comment on later…….gotta get to work.

6brnorma... it was a nightmare getting it out with the sheave attached. And I made it especially hard by working outside on uneven ground with a chain block and makeshift gantry. It would have been much easier on a level concrete floor with a proper engine hoist. Lots of stuff has to be removed in order to rotate the engine, but the hardest part part is removing the left side engine mount.
Yes I intend to remove the wheels and work on the axles. I hope 3 of them are OK, but the left rear leaks badly and definately needs attention. The chains, clutches, liners, and sprockets are all OK.
The sheave eventually came off with plenty of heat and pressure. And the flywheel came off after I ground some small grooves into the hub so the puller would stay on. (You can just see them in the pic below.)
The reason everything on this Bobcat is so hard to undo is because it sat outside in salty sea air for years. Every bolt on the frame is rusted deep into the threads. Most would not budge with any amount of penetrating oil or rattle gun persuasion. So, besides the puller set, the other invaluable tool has been the nut splitter set. ($26 on ebay) Its amazing how easily a splitter loosens up a totally rusted nut. You don't need to actually split the nut, you just have to apply a bit of pressure to a couple of facets of the nut and it distorts it enough to break the internal rusted bond. It can then be easily removed with a spanner. Many of the nuts will even be re-usable. I wish I'd discovered these nut splitter gadgets years ago.
One thing you might notice in the engine bay picture above is the large black hose running from the valves to the fluid distributor block. Because I have a 'fixed' variable speed sheave I removed the variable speed valve and and fitted this hose in its place. The hose is a bit long but it was a mis-made hose the shop had in their rejects box so I got it for just $30.

 

[alchemysa]

6brnorma... it was a nightmare getting it out with the sheave attached. And I made it especially hard by working outside on uneven ground with a chain block and makeshift gantry. It would have been much easier on a level concrete floor with a proper engine hoist. Lots of stuff has to be removed in order to rotate the engine, but the hardest part part is removing the left side engine mount.
Yes I intend to remove the wheels and work on the axles. I hope 3 of them are OK, but the left rear leaks badly and definately needs attention. The chains, clutches, liners, and sprockets are all OK.
The sheave eventually came off with plenty of heat and pressure. And the flywheel came off after I ground some small grooves into the hub so the puller would stay on. (You can just see them in the pic below.)
The reason everything on this Bobcat is so hard to undo is because it sat outside in salty sea air for years. Every bolt on the frame is rusted deep into the threads. Most would not budge with any amount of penetrating oil or rattle gun persuasion. So, besides the puller set, the other invaluable tool has been the nut splitter set. ($26 on ebay) Its amazing how easily a splitter loosens up a totally rusted nut. You don't need to actually split the nut, you just have to apply a bit of pressure to a couple of facets of the nut and it distorts it enough to break the internal rusted bond. It can then be easily removed with a spanner. Many of the nuts will even be re-usable. I wish I'd discovered these nut splitter gadgets years ago.
One thing you might notice in the engine bay picture above is the large black hose running from the valves to the fluid distributor block. Because I have a 'fixed' variable speed sheave I removed the variable speed valve and and fitted this hose in its place. The hose is a bit long but it was a mis-made hose the shop had in their rejects box so I got it for just $30.

In the process of cleaning up this engine for the rebuild I discovered something that really surprised me.
Maybe I've overlooked something but this is how it appears to me...
The oil filter on the VH4D engine filters the oil AFTER it has run through the fine internal spray jets that lubricate the internal components of this engine. In other words raw 'dirty' oil, straight from the sump, is pumped to the jets. Only a coarse wire screen on the oil pickup provides any filtering of the raw oil but, as you can see in the second pic, the holes in the wire screen are larger than the hole in the oil jet. The oil filter canister (when fitted) is actually the LAST component in the lube system before the oil returns to the sump.
Not surprisingly 2 of the 4 jets were clogged in my dirty old engine. If the lubrication of everything, including pistons, is dependent on these jets then obviously this is a serious problem.
It then occurred to me that perhaps the oil in the sump is also splashed onto the crankshaft by the downward movement of the crankshaft counterweights. But no, as you can see in the last pic, the green 'full oil' line is well below the lowest arc of the counterweights.
I know these engines have been around for decades but this almost seems like a design thats doomed to fail.
The oil jets can be got at and cleaned by removing the plugs on the side of the engine and poking with a wire, but unfortunately that requires that all the components on the right hand side (the rear of the Bobcat) are removed. Pic 3 shows the inner oil jacket into which the jets are screwed.

 

[alchemysa]

In the process of cleaning up this engine for the rebuild I discovered something that really surprised me.
Maybe I've overlooked something but this is how it appears to me...
The oil filter on the VH4D engine filters the oil AFTER it has run through the fine internal spray jets that lubricate the internal components of this engine. In other words raw 'dirty' oil, straight from the sump, is pumped to the jets. Only a coarse wire screen on the oil pickup provides any filtering of the raw oil but, as you can see in the second pic, the holes in the wire screen are larger than the hole in the oil jet. The oil filter canister (when fitted) is actually the LAST component in the lube system before the oil returns to the sump.
Not surprisingly 2 of the 4 jets were clogged in my dirty old engine. If the lubrication of everything, including pistons, is dependent on these jets then obviously this is a serious problem.
It then occurred to me that perhaps the oil in the sump is also splashed onto the crankshaft by the downward movement of the crankshaft counterweights. But no, as you can see in the last pic, the green 'full oil' line is well below the lowest arc of the counterweights.
I know these engines have been around for decades but this almost seems like a design thats doomed to fail.
The oil jets can be got at and cleaned by removing the plugs on the side of the engine and poking with a wire, but unfortunately that requires that all the components on the right hand side (the rear of the Bobcat) are removed. Pic 3 shows the inner oil jacket into which the jets are screwed.

Sorry about the size of the pics above. If I could delete them and make them smaller I would but its too late now. <p? Also, the plugs behind the spray jets mentioned above are on the left side not the right side. But anyway its the rear of the Bobcat.

 

[alchemysa]

Sorry about the size of the pics above. If I could delete them and make them smaller I would but its too late now. <p? Also, the plugs behind the spray jets mentioned above are on the left side not the right side. But anyway its the rear of the Bobcat.

Yippee, my parts have arrived from the U.S. so the engine rebuild can commence.
My badly worn Wisconsin VH4D engine currently has 20 thou oversize pistons. My original plan was to fit sleeves and return it to stock size but that was going to get expensive, especially if anything went wrong. So I have now decided to fit 40 thou oversize pistons. Initially I did not consider this was an option as I could not find 40 thou pistons at a good price, but then I found this Agkits crew offering 40 thou (and 60 thou) oversize pistons. A kit with 4 pistons, rings, wrist pins, shell bearings, and upper gasket set was $338 US. Now I can take the jugs to get them bored out. (That'll cost about about $260 US).
http://www.agkits.com/wisconsin-vh4d-gas-inframe-overhaul-engine-rebuild-kit.aspx#.V_TITiRv5yh
Some other bits came from Rock Creek Consulting. They advertise Wisconsin parts on US Ebay and I think his prices are pretty good. From him I ordered a complete engine rebuild gasket set (only about $35), valve guides, full set of head bolts, oil seals for each end of the crank shaft, spark plugs, oil filter, and flywheel key. (I'll now have 2 sets of upper gaskets but thats OK).
http://www.ebay.com/itm/Complete-Wisconsin-Engine-Gasket-Set-for-VH4D-W4-1770-VF4D-READ-AD-/162215103743?hash=item25c4c60cff:m:mPq_qEC9ZgXhA-TZe-Ndh8w
(Below). A sample of the bits. It doesn't look much does it... but 'internally' theres really not much to these engines.

 

[Tazza]

Yippee, my parts have arrived from the U.S. so the engine rebuild can commence.
My badly worn Wisconsin VH4D engine currently has 20 thou oversize pistons. My original plan was to fit sleeves and return it to stock size but that was going to get expensive, especially if anything went wrong. So I have now decided to fit 40 thou oversize pistons. Initially I did not consider this was an option as I could not find 40 thou pistons at a good price, but then I found this Agkits crew offering 40 thou (and 60 thou) oversize pistons. A kit with 4 pistons, rings, wrist pins, shell bearings, and upper gasket set was $338 US. Now I can take the jugs to get them bored out. (That'll cost about about $260 US).
http://www.agkits.com/wisconsin-vh4d-gas-inframe-overhaul-engine-rebuild-kit.aspx#.V_TITiRv5yh
Some other bits came from Rock Creek Consulting. They advertise Wisconsin parts on US Ebay and I think his prices are pretty good. From him I ordered a complete engine rebuild gasket set (only about $35), valve guides, full set of head bolts, oil seals for each end of the crank shaft, spark plugs, oil filter, and flywheel key. (I'll now have 2 sets of upper gaskets but thats OK).
http://www.ebay.com/itm/Complete-Wisconsin-Engine-Gasket-Set-for-VH4D-W4-1770-VF4D-READ-AD-/162215103743?hash=item25c4c60cff:m:mPq_qEC9ZgXhA-TZe-Ndh8w
(Below). A sample of the bits. It doesn't look much does it... but 'internally' theres really not much to these engines.

I'd have thought those parts would have cost a lot more than that. Older engines seem to attract higher parts prices, glad this was not the case.
I hope the rebuild goes smoothly from here on.

 

[alchemysa]

I'd have thought those parts would have cost a lot more than that. Older engines seem to attract higher parts prices, glad this was not the case.
I hope the rebuild goes smoothly from here on.

Tazza.. I'm very pleased with the prices for parts for the Wisconsin donks. Being just a petrol engine helps of course. Seems like theres plenty of these engines around, and and some 'not too greedy' parts suppliers in the U.S.
Stock size pistons would have been even cheaper. I actually priced oversize pistons here in Adelaide. They wanted $200 EACH!! Many of the smaller/cheaper US suppliers don't want the hassle of sending overseas but fortunately I have a friend in North Carolina who will forward the parts to me.
As for the rebuilding ... it should go OK. I have about 20 plastic bags with big Texta labels . Even simple stuff like 'Sump bolts' I label. Its so easy to forget where things go, especially when its a long, drawn out rebuild.

 

[Tazza]

Tazza.. I'm very pleased with the prices for parts for the Wisconsin donks. Being just a petrol engine helps of course. Seems like theres plenty of these engines around, and and some 'not too greedy' parts suppliers in the U.S.
Stock size pistons would have been even cheaper. I actually priced oversize pistons here in Adelaide. They wanted $200 EACH!! Many of the smaller/cheaper US suppliers don't want the hassle of sending overseas but fortunately I have a friend in North Carolina who will forward the parts to me.
As for the rebuilding ... it should go OK. I have about 20 plastic bags with big Texta labels . Even simple stuff like 'Sump bolts' I label. Its so easy to forget where things go, especially when its a long, drawn out rebuild.

$200 each? that is robbery! The interenet makes it so much easier for us to get good prices on parts rather than having to pay the sometimes insane prices suppliers put on parts.
I know what you mean about issues with not everyone wanting to export, i am having that issue right now with getting a “restricted” part out of the USA.

 

[6brnorma]

$200 each? that is robbery! The interenet makes it so much easier for us to get good prices on parts rather than having to pay the sometimes insane prices suppliers put on parts.
I know what you mean about issues with not everyone wanting to export, i am having that issue right now with getting a “restricted” part out of the USA.

Alchemysa……check and make sure that crank seal fits on both ends. I know of four different seals for those engines and that number doesn't cross to any of them. I'm not saying it won't work…….just double check. Also……I can't tell from the pic but you may need to flip that ring gear over…..it may be just fine, can't really tell.
Keep us updated on the temps of your engine when you finish…….I've always been afraid to go .040 over in this engine due to the extreme temps we have here so I go .030 and that's it. This will be interesting.

 

[alchemysa]

Alchemysa……check and make sure that crank seal fits on both ends. I know of four different seals for those engines and that number doesn't cross to any of them. I'm not saying it won't work…….just double check. Also……I can't tell from the pic but you may need to flip that ring gear over…..it may be just fine, can't really tell.
Keep us updated on the temps of your engine when you finish…….I've always been afraid to go .040 over in this engine due to the extreme temps we have here so I go .030 and that's it. This will be interesting.

6brnorma... Rock Creek Consulting alerted me to the variety of oil seals so I sent them pics of the two end cases to ensure I got the correct seals. The gear case end is SKF #14875, the same number as the old seal. The sheave end seal #14211 is a Chicago Rawhide seal in a SKF box. There is no discenable number on the old 'cork' seal but its the same size so I am confident it will fit.
Regarding the 40 thou oversize pistons. The wear on the bores required more than a 10 thou shave so I couldn't use 30 thou pistons. I had 'for and against' opinions about going 40 thou oversize. Rock Creek Consulting advised that if going above 30 thou its best to fit sleeves then revert to stock size pistons. Initially I liked this idea. The sleeves were only about $40 each and pistons were only about $150 a set. But the local engine shop here was luke warm on the idea of using customer supplied sleeves because it doesn't give them any margin for error. They suggested that sometimes the sleeves can go in a bit wonky, requiring a second round of boring. Their preferred option was to bore, fit their own sleeves, then rebore to take the stock pistons. Regardless of how it was done, sleeving was going to get expensive.
So the next option was to use 40 thou pistons requiring only a single session of boring. The old Wisconsin 'expert' I spoke to over here thought 40 thou oversize should be fine so I'm going with it. I shall certainly you informed.
Good point about the rings. I shall follow the instructions carefully.

 

[6brnorma]

6brnorma... Rock Creek Consulting alerted me to the variety of oil seals so I sent them pics of the two end cases to ensure I got the correct seals. The gear case end is SKF #14875, the same number as the old seal. The sheave end seal #14211 is a Chicago Rawhide seal in a SKF box. There is no discenable number on the old 'cork' seal but its the same size so I am confident it will fit.
Regarding the 40 thou oversize pistons. The wear on the bores required more than a 10 thou shave so I couldn't use 30 thou pistons. I had 'for and against' opinions about going 40 thou oversize. Rock Creek Consulting advised that if going above 30 thou its best to fit sleeves then revert to stock size pistons. Initially I liked this idea. The sleeves were only about $40 each and pistons were only about $150 a set. But the local engine shop here was luke warm on the idea of using customer supplied sleeves because it doesn't give them any margin for error. They suggested that sometimes the sleeves can go in a bit wonky, requiring a second round of boring. Their preferred option was to bore, fit their own sleeves, then rebore to take the stock pistons. Regardless of how it was done, sleeving was going to get expensive.
So the next option was to use 40 thou pistons requiring only a single session of boring. The old Wisconsin 'expert' I spoke to over here thought 40 thou oversize should be fine so I'm going with it. I shall certainly you informed.
Good point about the rings. I shall follow the instructions carefully.

Interesting……so does that seal actually have a 14211 stamp on it or was it just the box? If it does not work….let me know, I think I have some of the 'cork' seals in stock and I would send you one. If it does work……I'd like to try one out myself. Yes, the 14875 is the most common seal.
I've always felt the .040 would work but since I have quite a selection of old 'jugs' sitting around, I've never had the need to go over .030……you're doing great.

 

[alchemysa]

Interesting……so does that seal actually have a 14211 stamp on it or was it just the box? If it does not work….let me know, I think I have some of the 'cork' seals in stock and I would send you one. If it does work……I'd like to try one out myself. Yes, the 14875 is the most common seal.
I've always felt the .040 would work but since I have quite a selection of old 'jugs' sitting around, I've never had the need to go over .030……you're doing great.

Yes its actually stamped on the seal.... CR14211USA

 

[alchemysa]

Yes its actually stamped on the seal.... CR14211USA

I have too many things in pieces, so before starting the engine assembly I figured I better finish the control valves.
Theres not much to these things really. Like most things on this Bobcat they look a bit daunting at first but are actually pretty simple. After cleaning 2 inches of rock hard dirt and oil off the valves I found they really only consist of these bits shown in the pic below plus the 3 spools.

But of course this unit needed more than just a cleanup. Two of the spools had deep rusty pits at the linkage ends. After grinding the rust with a cheap little hand grinder I had 10 holes about 1 mm deep. Some were 3 or 4 mm long. The recommended solution for this problem is usually to buy expensive new spools (if they available) or have them professionally repaired and hard chromed. (Also very expensive). Time will tell if my redneck fix will hold up.

My first patch-up attempt (below) was with Permatex. After letting it set for a few days I filed it down to a nice glass smooth surface. It looked great but I wasnt satisfied that it was sufficiently bonded to the metal. I was able to pick it out of the holes too easily. So, after grinding the holes out again I had a good think, and decided to try soldering it. Solder material isn't particularly hard of course but I figure in my case these patches are not going to be getting a real lot of work and anyway they are really just rubbing up against a rubber ring.

You cant do this with a soldering iron. You need plenty of heat, but thats not hard to arrange. The gas torch was only about $6 on Ebay and the gas cans are about 4 for $4 when on special at the hardware store. The 'Plumbers Solder' kit containing solder wire and flux was about $25.

After a fair amount of trial and error (and grinding out the holes a few more times) I worked out that the best way to solder these shallow holes is like this... (1) Paint some flux onto the spool and onto the wire. (2) Heat the spool until its hot enough to melt the solder on contact. (3) As soon as you have a pool of molten solder in the hole press it down with a very hot knife blade. If you don't do this it just tends to sit in the middle of the hole and doesn't bond to the edges.

It looks a mess at first but once you clean up the splatter you should be left with some easy to file patches.
The two spools on the left were patched with solder but after filing down the solder I found I still had a few pinholes around the edges of some of the larger holes. The solution here was to clean out the pinholes with a pointed engraver tool and fill them with Permatex. The spool in the middle shows this. The little brown dots around the edge of the solder are actually pinholes filled with Permatex. I'm pretty confident the stuff will stay put in these pinholes.
The spool on the right presented a different problem. It had no deep pitting, but the chrome had been eaten away from the end that was exposed to the open air. To prevent further deterioration I took it to a zinc plater and had it masked off and plated. The line at the chrome/zinc interface looks significant but once I ran over it with a fine flat file it can barely be felt.
Its all back together now with new 'quad' sealing rings. I've got plenty to do before I can put this to the test but I'm reasonably optimistic it will be an adequate fix.

 

[6brnorma]

I have too many things in pieces, so before starting the engine assembly I figured I better finish the control valves.
Theres not much to these things really. Like most things on this Bobcat they look a bit daunting at first but are actually pretty simple. After cleaning 2 inches of rock hard dirt and oil off the valves I found they really only consist of these bits shown in the pic below plus the 3 spools.

But of course this unit needed more than just a cleanup. Two of the spools had deep rusty pits at the linkage ends. After grinding the rust with a cheap little hand grinder I had 10 holes about 1 mm deep. Some were 3 or 4 mm long. The recommended solution for this problem is usually to buy expensive new spools (if they available) or have them professionally repaired and hard chromed. (Also very expensive). Time will tell if my redneck fix will hold up.

My first patch-up attempt (below) was with Permatex. After letting it set for a few days I filed it down to a nice glass smooth surface. It looked great but I wasnt satisfied that it was sufficiently bonded to the metal. I was able to pick it out of the holes too easily. So, after grinding the holes out again I had a good think, and decided to try soldering it. Solder material isn't particularly hard of course but I figure in my case these patches are not going to be getting a real lot of work and anyway they are really just rubbing up against a rubber ring.

You cant do this with a soldering iron. You need plenty of heat, but thats not hard to arrange. The gas torch was only about $6 on Ebay and the gas cans are about 4 for $4 when on special at the hardware store. The 'Plumbers Solder' kit containing solder wire and flux was about $25.

After a fair amount of trial and error (and grinding out the holes a few more times) I worked out that the best way to solder these shallow holes is like this... (1) Paint some flux onto the spool and onto the wire. (2) Heat the spool until its hot enough to melt the solder on contact. (3) As soon as you have a pool of molten solder in the hole press it down with a very hot knife blade. If you don't do this it just tends to sit in the middle of the hole and doesn't bond to the edges.

It looks a mess at first but once you clean up the splatter you should be left with some easy to file patches.
The two spools on the left were patched with solder but after filing down the solder I found I still had a few pinholes around the edges of some of the larger holes. The solution here was to clean out the pinholes with a pointed engraver tool and fill them with Permatex. The spool in the middle shows this. The little brown dots around the edge of the solder are actually pinholes filled with Permatex. I'm pretty confident the stuff will stay put in these pinholes.
The spool on the right presented a different problem. It had no deep pitting, but the chrome had been eaten away from the end that was exposed to the open air. To prevent further deterioration I took it to a zinc plater and had it masked off and plated. The line at the chrome/zinc interface looks significant but once I ran over it with a fine flat file it can barely be felt.
Its all back together now with new 'quad' sealing rings. I've got plenty to do before I can put this to the test but I'm reasonably optimistic it will be an adequate fix.

Excellent work alchemazing………that's sure a lot cheaper then my system.

 

[Tazza]

Excellent work alchemazing………that's sure a lot cheaper then my system.

Nice job indeed, It amazes me that there are no protective boots covering the exposed part of the spools.
Never would have thought of usind soft solder, not hot enough to mess with the temer of the metal either.

 

[6brnorma]

Nice job indeed, It amazes me that there are no protective boots covering the exposed part of the spools.
Never would have thought of usind soft solder, not hot enough to mess with the temer of the metal either.

The lack of a protective boots was a major problem for these early machines……especially since so many of them were used in barnyard, poultry and dairy situations. Valve sat where it collected all sorts of manure and urine……not a good situation.

 

[alchemysa]

The lack of a protective boots was a major problem for these early machines……especially since so many of them were used in barnyard, poultry and dairy situations. Valve sat where it collected all sorts of manure and urine……not a good situation.

Well most of the engine is back together. Its been rebored and the new pistons are are in. Now its a matter of reattaching all the bits and pieces. I'll paint the outer cooling panels but the engine itself can stay as it is.
This is the housing for the distributor and the hydraulic pump coupling. It had no oil seal on the outer end and was leaking so it needed a fix of some kind.
I managed to break it at both ends while I was trying to dismantle it. The trouble was that the Woodruff key for the drive gear had sheared and the gear had spun until it welded itself to the shaft. I simply could not press the gear from the shaft while it was still in the housing so I eventually had to press the shaft from the small end. Consequently I broke the lip that holds the large circlip that retains the main bearing. My fix for this looks rough but its effective. I just welded some dobs of metal to the housing then cleaned out the groove with a dremel. It holds the circlip nice and securely.
At the outer end of the housing (the pic on the right) theres supposed to be an oil seal but it was missing and there was nothing to indicate how it fitted anyway. The parts book doesnt give any clues either. There was only about 2mm of lip; not enough to retain a seal, and the end was pretty chewed up so I couldn't tell if the bearing was removed by pressing it inwards or outwards. I chose poorly and pressed it the wrong way (from the inside) and cracked the lip of the housing in a couple of places. Fortunately I stopped before I really wrecked it and was able to hold it together with a few more welds. (Its rough but it seems strong enough. I have no experience welding these cast pieces so I didn't want to muck around with them too much). Fortunately the bearing was OK and could be re-used.

That still left me with the problem of how to fit an oil seal. I ordered a seal from the US but when it arrived it just didnt seem right. It fit the shaft perfectly but the outer diameter was too small. To solve this I fitted the seal inside a 1/2" length of aluminium pipe that I had lying around. I had to lathe just a little bit out of the inside of the pipe the get the seal to fit snuggly. The outer diameter of the pipe fitted nicely into the hole in the end of the housing but of course it wasn't oil tight so I bogged the whole thing together with Permatex. Unfortunately I didnt take a good photo before I fitted the coupling and bolted it back onto the engine. Only time will tell how effective this all is but I think it will be OK. I'd still like to know how the correct seal is supposed to fit.
I spent a lot of time getting the metal couplings on the drive and the hydraulic pump 'just right'. The original setup was badly aligned and the couplings were running 'metal on metal'.

 

[alchemysa]

Well most of the engine is back together. Its been rebored and the new pistons are are in. Now its a matter of reattaching all the bits and pieces. I'll paint the outer cooling panels but the engine itself can stay as it is.
This is the housing for the distributor and the hydraulic pump coupling. It had no oil seal on the outer end and was leaking so it needed a fix of some kind.
I managed to break it at both ends while I was trying to dismantle it. The trouble was that the Woodruff key for the drive gear had sheared and the gear had spun until it welded itself to the shaft. I simply could not press the gear from the shaft while it was still in the housing so I eventually had to press the shaft from the small end. Consequently I broke the lip that holds the large circlip that retains the main bearing. My fix for this looks rough but its effective. I just welded some dobs of metal to the housing then cleaned out the groove with a dremel. It holds the circlip nice and securely.
At the outer end of the housing (the pic on the right) theres supposed to be an oil seal but it was missing and there was nothing to indicate how it fitted anyway. The parts book doesnt give any clues either. There was only about 2mm of lip; not enough to retain a seal, and the end was pretty chewed up so I couldn't tell if the bearing was removed by pressing it inwards or outwards. I chose poorly and pressed it the wrong way (from the inside) and cracked the lip of the housing in a couple of places. Fortunately I stopped before I really wrecked it and was able to hold it together with a few more welds. (Its rough but it seems strong enough. I have no experience welding these cast pieces so I didn't want to muck around with them too much). Fortunately the bearing was OK and could be re-used.

That still left me with the problem of how to fit an oil seal. I ordered a seal from the US but when it arrived it just didnt seem right. It fit the shaft perfectly but the outer diameter was too small. To solve this I fitted the seal inside a 1/2" length of aluminium pipe that I had lying around. I had to lathe just a little bit out of the inside of the pipe the get the seal to fit snuggly. The outer diameter of the pipe fitted nicely into the hole in the end of the housing but of course it wasn't oil tight so I bogged the whole thing together with Permatex. Unfortunately I didnt take a good photo before I fitted the coupling and bolted it back onto the engine. Only time will tell how effective this all is but I think it will be OK. I'd still like to know how the correct seal is supposed to fit.
I spent a lot of time getting the metal couplings on the drive and the hydraulic pump 'just right'. The original setup was badly aligned and the couplings were running 'metal on metal'.

Just to clarify. In the pic above, the Permatex isn't structurally holding the housing together. Its just retaining the oil seal.