NB Ocelot

I now have muliple Blogs

My new Blog will be about the tours of the waterways on NB Ocelot. Reporting on the events, incidents and people I meet along the way.

http://nbocelot.blogspot.com/

I will, of course, continue to report on progress of the National. But there are a few things that need doing to Ocelot before the winter.

A Slight Pause

My last entry said that I was a bit short of funds.

Its now time to confess why!

I have to admit that I've gone over to the dark side. As a fellow blogger put it, "...been seduced by the sirens of Dursley".

In plain terms, I've bought a Lister JP3. The up side was that it is wrapped in a 56' Steve Hudson shell (and interior).

I couldn't help it. I fell in love:

Oh.... It's got a bed, bathroom, kitchen and lounge to!

So what will happen to the National. Simple.... work will continue. All be it at a slightly slower pace. To be fair, it will probably become a winter project.

I suppose I'll have to start an 'Ocelot' blog now.

Dry Build

Lack of funds are holding up the engineering work on the crank, bearings, pistons and liners; but that is not stopping progress at the moment.

When you get an engine as a box of bits (all be it a big box! - well actually a 7x5 trailer and back of an estate car sized box), there is always that feeling in the back of your mind.... have I got all of the bits?

In fairness to Lionel, he had stripped it down and meticulously labeled almost everything, even putting nuts and bolts in little bags with labels on them.

When I did the first sort of inventory of bits, the only obvious thing I found missing was a pushrod. I did of course miss the fact that the crankshaft counter weights had gone AWOL http://d3national.blogspot.com/2008/01/new-year.html but this was a minor oversight.

What I had never done, was to open up all of those small packets of nuts and bolts.

Another task (bear with me) is to make all of the joints for the various components.

With these two tasks in mind, I came to a decision. The best way to check on the nut and bolt inventory and assess what joints were needed where would be to carryout a 'dry build'.

The result:

Now, it's not time to get to excited as its all got to come apart again, but it does give an impression of the finished article.

I also now know of a few studs that need to be replaced and a couple of nuts that are missing. Additionally it has helped me find a few places (on the machines surfaces of the castings) that need to be painted before final assembly as they will be virtually impossible to get too once assembled.

A useful exercise and it does raise the level of hope!

Engine Mounting and Bugger!

A while back I posted an entry about the construction of the engine bed and the fun and games had with drilling the engine mounting holes.

Well…. I made a decision about the mounting method and have gone for a modern product call ‘TICO S’. A "High performance machinery mounting pad", according to the manufacturers.

http://tiflex.co.uk/tico_s/tico-on-line/tico-on-line.html

It comes in various guises, but I bought a strip of the stuff 100mm wide (4" in old money) by the standard 12.5mm deep. I also bought some of their TICO S washers.

The engine is to be mounted on the TICO strip and the bolts have TICO washers at the top of the engine. This has effectively cushioned the engine between the TICO material and should absorb a lot of the vibration but still hold it firmly to the engine bed.

The ‘Bugger’ bit?

Well… Whilst carrying out this exercise I noticed an error in the engine bed manufacturing process.

I welded the cross members between the longitudinal members at the engine mounting points. This would give the frame the most strength/rigidity at the mounting points. Fine at the front (this will be effectively covered by the flywheel overhang). A problem at the rear though.

The National has a sump that is separate to the crankcase. The clearance from the bottom of the crankcase to the top of the rear cross member is 4.1/4". What’s the depth of the sump?… 5.1/4" ……. Bugger!

I’ve now got to ‘notch’ out at least 1" from the top of the rear cross member. A bit of an exercise if the engine bed had been built of wood, but its not. It’s built from 6mm structural steel!

It’s been a while since I’ve used a gas axe. Man the fire extinguishers!

Still, at least I’m dealing with these problems in the comfort(?) of the garage. Imagine trying to do it having just lowered the engine in through the roof of your boat on to an engine bed that had just been welded to the bottom plate of your Narrowboat!

Happy days!

Flywheel

'Flywheel'

It's quiet a boring heading I know, but I have finally attacked the flywheel.

Originally the engine had an industrial flywheel (as can be seen on the blog header). This would have been a problem as it did not have any teeth for an electric starter (the engine being hand start only). However, a suitable toothed marine flywheel that matched the crankshaft mounting was supplied with the engine.

So, as per usual, the task in hand was to remove all of the paint back to bare metal.

How much paint can a flywheel have on it! There were layers of the stuff!

There's a lot more surface area to a flywheel than you think. Several tins of paint stripper and many hours with a wire brush and the thing was cleaned up.

One thing it did reveal on the inner boss was the stamping 49909. Could this have been the engine number of the 'donor' engine? If it is; thank you 49909, because your flywheel is now going to be well and truly bolted to the front of 56214. And long may it remain there (mainly because its to blood heavy to get off!).

Of course, once you get all of the old paint off and get the metalwork cleaned up, you've got to put the new stuff on. The result is:

A nice big black shiny flywheel!

Oh........ and another thing. The previous entry was with regard to the water pump. Well, here's a picci of the finished item assembled in full. I think it looks great against the black of the engine (the picci doesn't do it justice and it looks better in the flesh)

Water Pump

Really sorry for the lack of updates. I know its been the best part of a month. Unfortunately things like w##k and maintenance on the home have been taking a bit of a priority of late. I know its not good enough - but that's the fact's.

Anyway, what have I been up to. Not a great deal, but there has been a little tinkering hear and there when the opportunity arises.

The current semi project has been the water pump drive unit.

The water pump is a plunger type unit that is powered via the fuel pump cam shaft.

A set of skew gears turns the drive through 90 degrees and operates a brass plunger via an eccentric cam.

All very simple but, hopefully, very effective.

Obviously the first thing to do was to break it down in to its component parts so that every thing can be inspected and cleaned up.

In fairness, it was all in pretty good nick, so it then followed on with the usual (you know the score).

At the end of the task, another semi component is ready and wait for the great assembly process

I love the cam lubrication process. Remove cover by undoing brass wing nut, open the spring loaded reservoir cap and fill reservoir with oil. A wick feed then drips the oil down on the the 'big-end' of the plunger and trough via an oil way to the 'little-end' of the plunger.

Another little pre-start up job.

Once coupled up to the cylinder body, it will look the mutt's nutt's bolted to the side of the black beast.

I do need to make some new leather washers for the plunger. Anyone got any spare laderhosen?

Next up, I intend to attack the flywheel. It shouldn't be to much trouble apart from the many layers of paint and the sheer weight of the thing and the associated problems that that brings with it.

Watch this space!

Governor Case Re-build

Well, I've talked about it enough, so now it was time to actually do some work on the governor.

It's quite a lumpy bit of casing with a vertical shaft run direct from the crankshaft up through one side.

The large section at the top housed a set of spring loaded centrifugal weights and the shaft drives the oil pump at the bottom.

Obviously the first job was to strip it down in to its component parts. Then the usual cleaning up, etc, etc. Eventually it turns in to this:

The oil pump was in good condition and just needed a thorough clean up.

Once everything was cleaned up, all of the various component part that required painting had an initial coat of paint. Then it was time to put everything back together.

Ensuring the oil pump had the correct thickness of cover plate joint took a while. To thin and the gears were tight against the cover plate. To thick and there would be to much clearance between the cover plate and the gears which would result in a noisy and inefficient pump. The task was done by trial and error with multiple 0.5mm joints (all hand cut) until the correct thickness was achieved.

New joints where made for all of the other mating faces and, after a bit of fiddling around the final result:

Another bit ready to fit come the time of the great re-assembly.

Photo's

Any regular views may notice that there are a few more photo links.

I had a bit of a sort out of the photo's and have put them in to 10 basic categories.

Ignore the Photo Bucket cr#p and feel free to have a look.

Please let me know if any of the links don't work.

Engine porn at its best!

Edited to add:

A gentle slap on the hand from Sarah (see comments). There are a couple of acknowledgements I should really add.

The photos of the 'National Works' are courtesy of Sarah (NB Warrior). See: http://d3national.blogspot.com/2007/12/national-works-aston-under-lyne.html

The 'Engine Pre strip down' and 'Initial strip down' are courtesy of Lionel Knight: http://d3national.blogspot.com/2007/12/well-i-think-i-may-have-added-some.html

I think the rest are mine.

End Bed

Well, it was a weekend of cutting, grinding and welding. A bit of a change from degreasing, cleaning, stripping and wire brushing!

The result - an engine bed all fabricated up and ready for the re-build.

Its basically fabricated out of 75mm x 150mm channel (that's 6" x 3" in old money). The ultimate plan is to rebuild the engine from the bottom up, direct on to the bed plate. Get the gear box setup and aligned and once all finished and tested, the whole shooting match get transported up to the boat builder and welded in to place direct to the base plate.

Once fabricated, it was time to drill the holes for the mounting bolts. 21" apart and 20" along, 3/4" holes. Using the old adage of measure several times and drill only once, checking the diagonals to ensure they where all perfectly aligned, it drilled some 4mm pilot holes.

Before stepping up to eventually drill the full 3/4" holes; I 'dropped' the bottom end with the mounting legs on to the frame. Theoretically, the pilot holes should have been right in the centre of existing 3/4" leg holes.

Were they buggery!

Remove the bottom end, double check all of the measurements on the bed. Yes, everything was true and square. 21" x 20" with equal diagonals.

Check the engine legs (not an easy task with 2/3 cwt of engine bed floating in mid air on the hoist). Hole centres are 21" x 20". Equal diagonals - NO! The engine legs are pi##ed.

Take the legs off the Crankcase. Yep, they're fine. All of the original locating dowels are in place and true and the legs cannot be put on the 'wrong side' because the dowel won't allow it.

Put the legs back on, bolt them all. Re-check the measurements. Still askew!

Because the pilot holes have been drilled, the only answer now is to get a 3/4" hole saw and (after clamping the engine base to the bed) drill down through the leg holes and straight in to the base.

So much for the science of measuring and drilling as per the 'factory measurements'.

Hey Ho!

Governor and speed control

One of the big outstanding issues is the governor arrangement on the engine. The majority of Nationals and Russell Newbery engines have horizontal governors. Not the case in my engine.

It has its own casing that is mounted on the end of the timing casing and is a vertical arrangement. The centrifugal governor weights are at the top of a vertical shaft (with the connections to the speed controller and the fuel pump), whilst the oil pump is at the bottom.

To be fair, at the moment its a bit of an 'un-known' as to how well it will control engine speed throughout the required range of 250 - 1,000 rpm.

If the engine originated from a generating set, it is almost certainly set up to run at constant speed. The governor then adjusts the fuel rack to ensure a constant speed irrespect of load on the alternator.

On my linkage from the governor to the fuel pump there is a lever and cam arrangement. From what I can work out, this appears to be a rudimentary speed control. But how redamentary is it?

One school of thought is that it may be a speed controller to slightly adjust the 'constant running speed' for frequency control. Say +/- 20 rpm. If that is the case, it may prove difficult to control the lower speed ranges required (but not impossible!).

The other school of though is that it is full range speed controller. This is the one I like because it will work perfectly - forever the optimist! A few clues have revealed themselves:

1. All of the industrial generator sets that I have seen usually have the engine plate marked up as: '##hp at ####rpm' or 'operating speed: ####rpm', etc. My engine plate just gives Engine Type and Engine Number.

2. When I cleaned up the cam linkage it had two marks on it with arrows to a fixed mark. One said 'WORK', the other was unmarked (but why have it?). I'm hoping the unmarked arrow is 'idle'.

To be honest, until the Black Beast is fired up, I'll not know (unless anyone else knows differently??). Even if it is a constant speed unit, a bit a playing with the spring tension and cam profiles should be able to sort it (there goes the optimist again!).

Needless to say, it is now subject if stripping down, degreasing, cleaning, wire brushing, painting etc, etc.

Work and Play

The bank holiday weekend saw a little more progress on the engine combined with a bit of engine orientated socialising.

Sunday saw me pottering up to the Russell Newbery Works open day at Daventry. I wont bore you with to much detail, but rest assured that most of the talk was around RN's, but the National owners (3 of us I think) were present too!

Sarah on NB Warrior has more detail on her blog:

http://nbwarrior.blogspot.com/2008/05/i-can-not-believe-this.html

Note the cock up on the hand over of the pistons and liners - DOH!

What of the engine?

My previous post was about the template for the engine bed. Whilst I was thinking about ordering steel, I also thought about how I would eventually mount the starter motor and fabricate a suitable mounting bracket. The engine was originally hand start only and had a large industrial flywheel with no ring gear. Not to much of a problem as the engine came with a 'marine flywheel that should fit'.

One thing I had never done was check to see if it did. Probably because both of the two mating components (flywheel & crankshaft) were so damn heavy to shift around.

Whilst talking about this, anyone reading ye olde blogg who is considering rebuilding any engine of this ilk, please take in to account the weight of components that you will have to 'move around'. The flywheel is about 2 cwt, the block 2.75cwt, the crank is over 4' long and even things like timing covers make you grunt when you lift them. Every thing takes 3 times as long and twice as much effort!

Don't be put off though, its great fun (in a fairly masochistic sense).

Anyway, The sunshine saw me wheeling out the engine, putting together the 2 tonne engine hoist and lift up the flywheel to offer it up to the crank. Did it fit? Like a glove! The shoulder on the crank matched the recess of the flywheel, as did the bolt holes and diameters.




I then took various photograph and measurements so that I could look at working out how to mount the starter motor bracket (once it was fabricated - which is another job!).

Looking at the above photo you would expect the paint to be in fairly poor condition. Over about 30% of the area it was, the remaining 70% it was stuck like poo to a blanket. I spent a whole day stripping several layers of paint off the flywheel ready for the usual wirebrushing etc, etc. Again a job complicated by having to move a 2 cwt lump of metal around.

Engine Bed

I've stopped procrastinating and made a decision.

I’m going to mount the engine: flywheel at the forward end and the gearbox at the rear. If I took the propshaft of off the flywheel end, I had a 4" stub of crankshaft at the non-flywheel end to mount any drive pulleys for alternator(s), water pumps etc. Where as the flywheel has numerous holes to through mount an extension shaft to run anything.

Flange of off the 4" stub, flexible coupling, then into the gearbox. The gearbox mounted in its own frame just behind the engine and all bolted to the same engine bed.

I’ve also decided to wait for the new PRM 260 with a 1:1 ratio as well. Its currently being tested (still no timeframes for ‘launch to the market’) but it will be ideal for my requirements. 21" standard prop and 1 ½" shaft/stern gear.

Now that the decision is made, my thoughts turned to an engine bed.


My plan is to set up whole engine up on an engine bed as part of the rebuild process. Everything would then be bolted down and aligned etc before the whole thing was supplied to the boat builder. All that would then be required would be to weld the engine bed to the base plate.

The engine is sitting on a 2 tonne trolley during the rebuild and it has an excellent flat surface. I wanted to make a template so that I could confirm all of the dimensions, hole centres and crank alignment dimensions.


First thing was to get every thing of off the trolley and give it a good clean. Next I stuck sheets of A3 paper all over it and then carefully placed the engine back on it. It was then a case of marking around the engine feet and the mounting holes.

The next thing was marking the ends of the crankshaft to get the centreline. I did this by carefully ‘plumb-lining’ from the ends of the crank.


Lift everything off, and hey presto, one engine bed template.


Knowing the gearbox dimensions and allowing some space for the coupling in between, I have estimated the engine bed to be approximately 5’ long. In practice it may be a bit shorter, but its easy to cut a bit off!

The engine bed will now be constructed out of 3 x 6 ‘C’ section (75mm x 150mm in new money). A quick call to my local steel stockist confirmed 13’ of channel would be a shade over £100.

Covers etc

Although I haven't been blogging much of late, things have been happening (apart from liner measuring)

I thought that I had better show a little bit more of the progress.

The next string of shots are really before and after shots. Before being, various components wire brushes and cleaned ready for painting. The after being similar shots of the same components with paint on them.

First up is the 'Airbox'. This sits on the side of the block and is the common air filter box for all three cylinders. The individual intakes for each cylinder draw air out of one of the three elongated slots. The multiple slots face downward toward the bottom of the engine. The Airbox is another component which I found the engine number stamped on it. Each of the outlets were also stamped 1, 2 & 3 respectively as well. The two studs sticking out of the side of the box are for mounting the fuel filter on.

The frame below is located inside the Airbox and (allegedly) holds the wad of horse hair together.

I think I'll cheat and use moderns synthetic filter material.

Next up is a few cover plates. Top left in the photo is the crank end cover for the non flywheel end. Top right is an inspection plate for the governor casing. The bottom two are blanking plates for cylinders 1 & 3, waterside of the block.

Next up are a series of pictures showing the cylinder block inspection doors. Obviously one door on either side of the engine. One having the oil filler point.

At some point in time I'm going to have to make joints for all of these various covers. Break out the Klingerite and wad punches!

The Liner Wars (and Pistons)

Not so much a war - but I had to make a decision about the liners for the re-build.

NB Warrior kindly donated their old liners and pistons to see if they were better than mine. Now it was time to see which ones where the best.

There is no real alternative but to use good old fashioned measuring. And the measuring device – an internal micrometer of course.

Along came the evening when I had the house to myself. The liners duly found themselves on the kitchen table (hence the house to myself) all in a nice neat row.


Now I know, there’s only 5. The left hand three being mine the right hand two being ex’ Warrior (one never made it http://nbwarrior.blogspot.com/2008/03/even-goldfish-can-count-to-three.html)

The first measurement was the very top and very bottom of a liner. This confirms the original (non worn) diameter. Measurements are taken at 90 deg’ at each point to check to see how oval the bore is.

The reference measurements on my original liners was 4.125" (4.1/8th"). All three were spot-on.
Next was measuring the ‘worn area’. I was pleasantly surprised to find each liner gave the same readings of wear:
Longitudinally: 4.128 (3 thou wear). Transverse: 4.130 (5 thou wear) at the top of the stroke and slowly tapering out down to the original diameter as you went down the stroke. A max of 5 thou wear and 2 thou oval. Not a bad result.


Next up was the two (of three) liners from Warrior. The first difference was the original diameter. 4.135" top and bottom. They were both 10 thou oversize. The remaining measurements confirmed that the overall wear was of a similar pattern to mine but 1 thou less on each measurement.

The original factory spec was 4.1/8th" bore and 6" stroke. It would appear the Warriors liners, although slightly less worn than mine, have had a 10 thou re-bore in a previous part of their life.

Which ones to use – well, mine of course. I’ll have a chat with the machine shop, but I think a 5 thou hone from the original diameter to remove the oval bore and "the jobs a good un".

An examination of the pistons found them all to be of a similar condition. Mine have got the oil rings well and truly jammed in and are yet to be eased out. Both sets of pistons have slightly scuffed skirts, but nothing much to worry about. The ring groves are still tight and true. Overall, either set could be recycled with no problems.


All its going to take now is a trip over to Warrior to re-unite them with their 'bits'. Any excuse to see another National will do!

A useful exercise - and thanks to Jim & Sarah for the offer of their old liners and pistons.

A view of things to come

Well the block is finally painted with its couple of initial coats of paint.

I need to check the amount of 'free' crankshaft at the non-flywheel end of the engine. This will either be used to drive alternators etc or be coupled to a gearbox (the jury is still out on this one).

The only way to be sure was to assemble the timing cases on the end of the engine and break out the ruler. It was a nice day to day so I wheeled the engine out in to the freash air and:

A view of things to come?

It was then a case of bolt on the timing case and then the governer/oil pump casing.

The result? 4 inches. It doesn't sound much, but as the Actress said to the Bishop, "4 inches can make all the difference!"

Mmmm...... what to do?

Loads of Pistons!

It’s been over 10 days since the last entry. Sorry.

It's not that I haven’t been doing anything either. I’ve been doing bits here and there, plus a bit of socialising. I can’t spend all my time in the garage being "Billy –no mates".

The main thing of note is ‘pistons and liners’.

I want to try to keep the engine as original as possible (I may have mentioned this before - yawn). Anyway – to cut a long story short, Jim and Sarah of NB Warrior fame very kindly offered me Warrior’s old pistons and liners if theirs were better than mine (they had all of theirs replaced with new shiny alloy ones when RN re-built their engine).

Plans were made and we decided to attend a CWF Banter at Napton (last Monday). Pistons would be compared and exchanged there. As it happen, I went to the boat gathering at Stoke Bruerne on the Sunday, so did Jim & Sarah, and the exchange took place in the Museum car park.

In the end I’ve kept all of the pistons and liners so that I can measure them and decide what are best. On the face of it, Warriors liners appear to be hardly worn at all and I think they could easily be recycled after a slight hone. The pistons also look better and again. I think these can be re-used.

A few other bits finished off now are the rocker covers and the cylinder head air intakes.

They where a real pain to clean up and paint, but they look nice now.

Hopefully I’ll hear back from PRM soon about the gearbox and coupling arrangements, I can then get the crank etc sent off for machining. It’s sat in the garage at the moment ready to go.

Still... plenty of other things to do in the mean time. I really do want to attack the cylinder heads soon!