Josephine rebuild

[Keith Clements]

Another interlude as yesterday was spent taking Amy's cat to the vet. The cat was in a very poor state but after a day on a fluid drip, a night of attention and another day on a drip , she seems better. A close run thing. The jury is out on what it was. But we are looking for lillies.

Anyhow to double check on Philip's question I sorted through the box of pumps again, to find a broken one ( I think this was from the Welsh rally). I also found a very early one with small bore pick up pipe.


All use the same size gears.

I then decided I was not happy with the drive gear on the SA pump that I had put back in as it was worn.
I tried to do a dimensional assessment of the wear and came to the conclusion that visual is easier.

The worn gear is on the right.
The 'new' pump I had put in has a gear that has different dimensions which was perhaps paired with the new brass worm. Only bluing will prove this. But the used gears did show differences as to where the wear occurred, so perhaps some set up or checking is needed. Some wear only on part of the gear , others along its whole length. Some wear more on the tip, others on the full height of the tooth.

Anyhow whilst down the vet the postie tried to deliver my gauze . So I had to wait to go and collect today.



Shows the difference in mesh size.

All now installed and tested with a good spray out onto the worm gear.

[PJGD]

Keith,
Many thanks for checking on that for me; I have the later pump available to me and so had that gear dimension, and I simply assumed (and you know what that makes me!) that the earlier short body pump must have had a shorter gear in them. In retrospect, early engines with hydraulic tappets would have required a healthy oil supply, but then the later engine with solid tappets did not need as much oil to the lifters but needed more to the crank bearings due to the change to tri-metal bearing shells that run hotter than the early white metal shells.

I note that the JCL Service Notes Bulletin 59 from July 1951 discusses the introduction of the lip to the oil pick-up filter, with mention of the appropriate dimensions. Prior to that date, no lip was specified.

Philip

[Keith Clements]

The oil pump screw gear was put in with the longer boss towards the back. Careful manipulation and some trial and error was required to align the slot in the distributor drive with 1/2 TDC (the white mark on flywheel). Yellow mark is 3/4 TDC.

If this is incorrect, the distributor leads will be pointing the wrong way and the CB terminal may foul the water pump body. Note early dizzie has different orientation.

The key was inserted and timing chain sprocket with two centre pops facing outwards. The crank pulley was put on and operation of the gearing checked. There was NO backlash, not even a smidgen. Thumbs up for new gears. If I get a chance I will see what backlash there was on the old worn gears.

The dial micrometer was then set up on No 1 Inlet push rod and all clearance adjusted out of the tappet. The camshaft was rotated until at base of cam and the dial zeroed. Then the cam was turned until there was 13 thou or .33 mm lift.


The observant will note that the last picture shows the dial on the exhaust valve as I was checking lift.

Then the new timing chain was assembled with the link pushed in from the back. It is worth relaxing the timing chain by turning back the crank slightly. It makes it easier getting the pins in. The centre plate of the link was put in by folding back the outer links.


You can do the assembly on the bench at this stage as the sprockets are not yet fitted.
It is most important the chain is put on with the circlip at the front otherwise the pins of the link will destroy themselves or the screw gear.
A new lock plate was made and the 5/16 pin cleaned up with emery. I also made sure it was a sliding fit in all the sprocket holes.

The crank was then turned to 12 BTDC (the red mark)


The top sprocket large holes were aligned with the 5/16 screw holes.


and the closest aligned holes chosen to insert the dowel pin.

The crank was rotated through a couple of turns noticing total rocker lift was 1.55mm. There is an increase in valve lift due to lever action of rocker but a decrease due to tappet clearance.

The lift when the flywheel again reached the 12 deg BTDC was found to be .33 mm. Brilliant. So locking plate put on and bent over and checked again for good measure.

[Keith Clements]

I thought I would do a more thorough check on the rocker shaft so took it apart , cleaned and inspected. There was lot of sludge inside the shaft which took some shifting in the parts washer.

All the small oil ways were cleaned out with a drill.

and the shaft was checked for wear. I did not crack test but might be worth doing as I ( and Scott) have had one snap.

The rockers were also ground to lighten ( see earlier picture of racing shaft) and the tappet faces refaced to get rid of pitting.
All was reassembled and I reckon the springs on the end need to have their larger diameter coil pointing towards the rocker otherwise they eat into shaft because they get trapped.
Then found a bent pushrod when adjusting the tappets so had to select and clean up another. . The push rods should be turned when installed to make sure they do so without binding.
New rubber gasket in the rocker covers
Then put a new gasket on the timing cover and a new oil seal and fitted it.

[Keith Clements]

Completed timing cover installation , fitting pintel valve and tube, push rod covers, shortening of delivery pipe to water pump so that it fits Jupiter, yet to do oil filler pipe.
Made gearbox gasket and fitted reconditioned gearbox. Lifted down off stand and fitted in test bed.


Is there a hole missing?....layshaft! Note the paper gasket must also seal brass cowl so needs to be cut on brass cowl recess not the clutch housing recess. If it does not the brass cowl is loose in its housing.

[Keith Clements]

Slightly interrupted by rugby and the six nations and packing for my trip to India and Nepal, I progressed with installing the engine on the test bed.
The Jupiter engine mounts had to be changed to Javelin ones. I tried to modify a Javelin oil filler into a Jupiter one but failed to un-braze the screw thread. I may have to fit the original one.

The test bed frame needed some cutouts to accommodate the exhaust and the tappet covers needed a bit of grinding to fit the carb adapters. On one side I had to retain the paper gasket as the countersunk would not bed down, on the other I used the Loctite 501. Having had problems with intake tract sealing before (using Hylomar and paper)I thought I would try the 501 which is a metal to metal sealant. Sorry I did not take pictures of the carb adapter which is a 10mm thick plate with two 5/16 BSF countersunk screws pointing upwards to hold the Dellorto carb. A standard angled aluminium plate is modified to take two unequal length countersunk 5/16 BSF set screws to bolt it into the head. The two plates are joined by four unequal length countersunk 4 BA set screws with the angled plate tapped to take them.




The next issue is the water pump/fan as I may have to fit a Javelin one for the test bed.

[Keith Clements]

Here are a couple of pics of the carb adapter.



Since i could not fit the Jupiter water pump I lashed up this thermosyphon system. We will see how long it takes to overheat.


The head temperature sensors were wrapped in PTFE tape and inserted in the drain tap holes.


The heater pipe was also blocked off.
My spare electric petrol pump and a T piece with some plastic hose was used to supply petrol. Temporary of course. I wonder why Jowetts changed the feed on the Jupiter to separate pipes and did not use the Javelin arrangement. Could it be the Javelin suffered from vapourisation due to proximity of pipes and filter to engine heat?


The mechanical pump drive was blanked off. I have put a stud in here as it is all too easy to put in the wrong length bolts.


The Accuspark spark plugs with three spark gaps were put in.

The DM2 distributor with Accuspark electronic ignition was put in with a new set of ignition leads.
The starter motor was fitted and a battery used to try to turn the engine over. Battery needs charging so left overnight.

[Keith Clements]

It is well over a month since I last posted mainly because I have been in India and Nepal and then because I have been recovering from a bug I picked up on the plane coming back.

Before I left I did try to start the engine but failed. Since returning I have spent a few short days down the garage trying and checking various things.Checking for sparks at the correct time, compression on all cylinders, petrol in the right places but all to no avail. I also tried a high torque starter motor lent to me by Richard Gane.
It had taken me a while to sort out a petrol pump which worked. I had three which ticked but did not seem to deliver petrol at the right pressure. I also used a fresh can of petrol. I did get an occasional cylinder to fire.
A couple of days ago I replaced the electronic ignition for an original with points. I also changed back to single anode spark plugs.
Today I looked at the new ignition leads which showed a resistance of 90k so swapped them out for an old dizzie cap and copper leads. I think the spark was better and the car seemed to fire more easily, although still would not run.
I had rechecked valve timing. This afternoon now running short of causes I thought I would look at the valve opening periods. It really is something I should have done when fitting the new camshaft.
Subject to a recheck and confirmation with a known working cam this is what I discovered.
I checked cylinder one using the white mark on my crankshaft pulley and cylinder three using the yellow mark on my crankshaft pulley. The two marks are 180 deg apart.
I then judged the position of when the valve starts to open and finishes closing (also gauging approximately when it is fully open). Both cylinders seemed to be the same.

Inlet starts to open just before TDC (That is good because that is how it was set up on the 12deg BTDC mark). It had fully opened at 30 deg but was closed by 160 deg, which was about 80 deg too soon!

Exhaust opened at 90 deg (rather than 130 deg) and closed at 20 deg BTDC rather than 15 ATDC.

I need to sleep on this and ratify with a known good cam tomorrow. It also really needs to be done with a dial micrometer, although sight of the rocker and spinning the push rod are fairly good indications of opening and closing.

[Keith Clements]

Whilst redoing the valve timing for the third time the push rod on No. 1 inlet dropped and left a 5 mm gap. So that was the problem. I presume the new cam follower had a burr on it (probably the bronze push rod seat) that prevented it from going fully in. No 4 inlet had a similar problem. So that explained the short period of opening of the inlet valve and the mistiming of all the other valves. How that follower held its position through numerous checks on the tappet clearance, setting up of the valve timing many times and a few weeks of trial starting and turning over is hard to believe. Anyhow valve periods of opening now OK and will try starting today.
Sods law of course that it was on No 1 inlet!

[Keith Clements]

Started on first revolution once the valve timing was set up. Sticking cam follower was problem.

https://youtu.be/0TtzHPY1UfY

[Srenner]

How did you like the super starter? WOuld you rate it a good or useful upgrade?

[Keith Clements]

The starter is good, especially if you have a tight engine. It also turns over at lower battery power. I swapped back and forth between the two over the last few days.

Richard says it may be a tight squeeze on a Jav. The cost is probably comparable to an original replacement but I have so many second hand and really have not had many issues with them.


Changed back to the original test bed ignition coil so I have a known working test bed. Then put back the new ignition leads.

Then have to revert back to electronic ignition and three anode spark plugs.

A battery pack that stopped charging caught me out as the engine would not start. Eventually noticed its volts had gone down to 6.

[Keith Clements]

So after an interlude with Sam's block and repacking the display cabinets from the show, I filled the engine up with water and fired it up for a more exhaustive test.
The big fan had to be switched on as the paint on the exhaust burnt itself off.
There was a knock on the camshaft so the adjuster was screwed in and back 1/4 turn whilst engine stopped.
Oil pressure held at 75 psi, head temps rose to 85 but balanced with header at 75. (note there is no water pump or thermostat in circuit). Exhaust temps at 260C and even.

Revs well and held at 4000 rpm .
Vibration meter showed a consistent 7.7 mm/s at this speed dropping to 3.4 at 1000 rpm.

The engine seems well balanced so left as is, as yet have not a comparison with another.
Removed engine from test bed ready for installation .

[Keith Clements]

Some progress ..but slow.
Started by clearing up some of the stuff left from preparing for the Resto Show, testing the engine, doing Sam's block and just general untidiness!
I fitted the rear inner wings made from a pair of trailer wheel arches. These will protect the fragile aluminium wing from flying wheel weights and stones as well as keep all the muck and water from finding its way into sills and light fittings. Previously also fitted to Amy's SC they considerably reduce road noise as well.
The front part is cut to narrow it and to a certain extent reduce any muck from the front wheel going up over the arch.
Some trimming is done , but not a lot is required. A hot air gun can be used to form around the end of the sill.
The original 1/4 BSF captive nuts that held the original strip of aly inner wing were used to secure.

An additional stainless steel self tapper was used on the forward part of the arch

and three were also used to join the split in the arch.

This shows the rear which fits without modification.

The clearance was checked at full bump with a tape measure to give the same distance as between axle and bump stop (6 inches).
The plastic arch does need to be deformed by bending another 5 cm about 20 cm up using the heat gun so as to give enough clearance at the front of the tyre.
The front of the arch is then vertical for 20 cm rather than curving as made.

[Keith Clements]

The headlamp bowls that previously housed a pair of 7 inch lamps were straightened up (as they had met the tyre wall at Donnington) and checked in the apertures before being grit blasted and painted. A pair of late PF770 gaskets were ordered. Not from Holdens which were three times the price and out of stock!