A RUSTY RESCUE

By Staff
1 / 16
Peter Rooke’s latest project, a 3 HP IHC Model M.
2 / 16
The mixer after the needle valves and the air intake baffles had been removed.
3 / 16
The new lever for the tap, showing the tapped hole and special screw.
4 / 16
The new needle valve heads made out of steel rather than brass to match the original fittings.
5 / 16
The spring and baffle from the air intake.
6 / 16
New fuel pump ram, and retaining bush with new packing and spring.
7 / 16
The restored fuel mixer.
8 / 16
Repaired air intake baffle and freshly turned water pressure valve and seat.
9 / 16
The refurbished fuel pump.
10 / 16
Remains of old fuel tank.
11 / 16
Steel ball used to lap check-ball seat.
12 / 16
A small diameter tube bender.
13 / 16
Completed drain pipe fitting and draw-off pipe.
14 / 16
Adapted components of drain fitting.
15 / 16
The finished igniter.
16 / 16
The drain tap with new screw. The brazed hole is just visible in the base of the globe.

Editor’s note: Last issue, we began a three-part feature on
Peter Rooke’s latest restoration project. We continue below with
Part 2.

Fuel mixer

Like most fittings on this rusted engine, the fuel mixer needed
considerable attention.

It was necessary to give the body of the mixer a good clean with
a wire brush and all brass fittings were also removed. The fuel
reservoir was cleaned using kerosene and a small toothbrush. The
screw to hold the choke cover broke when I tried to remove it, so I
drilled the remainder then use a tap to re-cut the thread.

The lever on the tap to control/empty the fuel reservoir had
long since rusted away, making it difficult to remove the tapered
shaft. While it is possible to heat the shaft to pop it out, I do
not like using heat on cast iron unless I have no other option. An
alternative is to drill a hole in the base of the casting, using a
punch to press the taper out of its seat, then tap the hole and fit
a screwed plug to seal it. However, I had to make a new lever for
the tap and rather than peen the brass of the body over the new
lever to hold it in place, I decided to drill and tap the body for
a large head screw. The threaded hole could then be used for a
temporary bolt to help pull the shaft out.

Once the body of the tap had been extracted, its seating area
was cleaned. The top of the tap was faced off, the remains of the
old lever removed, and a new lever was drilled and filed to shape.
A brass screw was turned to hold the lever in place and the head
made over sized for a very shallow slot that could be filed when
the screw was firmly in place.

The needle valves had to be replaced and the state of the valve
seats was unknown. Some 5/16-inch brass was turned, then threaded
5/16-by-18-inch and tapered to match the originals. At the same
time that the lathe was set up to turn the taper, a piece of steel
was machined to copy the brass stems. Later, the steel was used to
lap the valve seats with very fine compound so the new valves would
be a good fit.

It was necessary to cut the rusted steel nuts from the brass
rod, which could be reused after cleaning the threads. The moving
baffle had to be replaced and a new one was fabricated by machining
some steel of different diameters then drilling holes before
brazing together. To complete this part of the repair a new spring,
shaped choke back plate and choke front plate were purchased.

There was no sign of any float valve moving in the water inlet,
despite prodding with a piece of wire to clear any dirt, so it was
necessary to remove the water pressure valve seat. Unfortunately,
it would not budge, despite resorting to the impact driver, so it
had to be drilled in order that all the accumulated dirt could be
cleaned out. A new alloy valve was made from some aluminium and
brass turned to copy the original seat.

To complete the mixer, new caps were made for the fuel
reservoirs and pointer for the needle valves.

Fuel pump

Like all other components, the fuel pump was seized solid and
the spring had virtually rusted away. The ram resisted all efforts
to remove it and, as the casting was badly rusted and undoubtedly
weakened, care had to be taken. The use of hydraulic pressure
through the out pipe to push up the ram, might have caused more
problems than it solved.

The top cap on the ram was removed by filing the peening holding
it in place, in order to remove it and the remains of the spring.
Fortunately, the check valve and the inlet pipe connector were
unscrewed without too much effort.

The pump was then rested upright and penetrant applied, and
allowed to work for a couple of days before gripping the top of the
ram with a pipe wrench, and gently twisting out while holding the
body of the pump in a vice.

Once the ram was out, the check ball in the bottom of the pump
was removed and stored safely until needed. The bore of the pump
was cleaned, and a length of brass, 7/16-inch, was inserted to test
the fit. It was slightly sloppy, so an adjustable reamer was used
to true up the bore, which ended up over-sized by 0.0001 before a
piece of brass was turned to a sliding fit to replace the old ram.
In any event, the ram needed replacement in view of the high amount
of uneven wear around the packing area. For the packing to seal
properly, the ram had to be parallel.

The brass collar to hold the packing in place had seen better
days, so while at the lathe a replacement was made from a piece of
scrap brass.

All the check valve needed was to be cleaned and dirt removed
from the check ball and its seat.

As the body of the pump was covered in rust pit marks, filler
was applied and sanded down so that the pump looked as good as new.
Before re-assembly, a steel ball 3/8-inch diameter, was fixed to a
piece of brass tube using an epoxy glue. Fine lapping compound was
applied and the ball used to polish up the check ball seat in the
pump. Kerosene and strips of clean rag on thin rods were used to
thoroughly clean any remaining lapping compound.

The original cap was reamed to fit the new ram, the top of which
was pin punched and peened over to hold it in place.

To pack the pump ram, to prevent leaks, soaped mop string or
graphited yarn should be used. While I used some leftover graphited
yarn, mop string probably lasts longer as it is not so susceptible
to attack by gasoline. While this is a kerosene engine, I intended
to run it on gasoline, which is cheaper in the United Kingdom.

The brass collar was fitted on the ram with the cone towards the
packing, so it compressed the packing around the ram. The
check-ball was inserted in the pump and the remaining parts
assembled.

Fuel pipe and fittings

The majority of the fuel pipes were damaged, so new pipe was
acquired ready for bending. Most of the original pipe was bent in
more than one place, so to save trial and error a piece of wire
coat hanger was bent by hand to the required shape for each section
of pipe and used as a template.

Before starting to bend the pipe, the new pipe was annealed by
heating to a dull red and allowed to cool slowly. It is best to
anneal pipe just before bending. If you leave it for several days,
it will harden again and require further annealing.

A cheap bending rig is normally adequate for brass pipe. It is
best to take your time, frequently stopping to check the amount of
bend to both the template and engine, as it can be difficult to
correct too much curve. Also allow a little extra at each end so
that it can be trimmed off in final fitting.

A couple of brass pipe fittings were missing, one of which had
an unusual thread (0.540 inches by 20 tpi.

Without taps for this non-standard thread, some round brass was
turned to the shape of the original female end. The internal hole
was drilled then bored before screw cutting the internal thread on
the lathe. Using the same settings, a piece of hexagon brass was
bored and screw cut for the new locking nut.

The next step was to turn brass to size for the male section and
cut the NPT thread with a die. The non-threaded ends of both pieces
were sawn with a 45-degree mitre and brazed together to form the
fitting, which after finish filing should look like the
original.

While brass fittings can be obtained some do not look like the
original, so to improve the appearance, a file can be used to
re-shape them. Filing down the threaded section of an oversized
street fitting, drilling and tapping an internal thread, it was
possible to make a close match to the original.

Fuel tank

There was little left of the original fuel tank, and for the low
cost involved, it was easier to order a replacement from Hit &
Miss Enterprises in the U.S. rather than make one. Apart from the
drain plug, fitting of everything was fairly straight forward after
making new steel pipes including a delivery tube.

The website of the late John Hammink
(http://www.oldengine.org/members/hammink/web/) provided
instructions on how to adapt a pipe fitting so the drain pipe from
the tank would line up with the hole in the body of the engine
casting. As a first step, a 35/64-inch hole was drilled in the
fitting and a piece of pipe threaded 1/4-inch-by-18 inches and
shaped to allow fuel to pass. The fitting needed to be trial fitted
to the drain pipe and when all looked satisfactory, it was brazed
together. I found that after brazing, I needed to grind a little
off one side of the fitting to get the necessary clearance.

To repair the take-off pipe, a length of brass pipe 1/4-inch
diameter, was soft-soldered to the male end of an elbow, with the
pipe being long enough so that it nearly reached the bottom of the
tank when the elbow was fully screwed into position.

When fitting the fuel tank, I found it easier to fit the
take-off pipes and elbow first, then the special elbow for the
drain pipe, wrapping gas proof PTFE tape around the threads for
leak proof joints.

The inlet pipe and the final length of the drain pipe were
fitted once the tank was bolted in place. The tank and underside of
the casting were given a good coating of anti-rust paint before
assembly.

Fuel filler pipe

A new fuel filler pipe was made out of 3/4-inch nominal pipe.
Again, a piece of wire was used as a template to assess the length
and the degree of the required bend. While the pipe was still
straight, the threads at each end were started by screw-cutting on
the lathe, then finished using dies. An end cap was screwed on one
end and the pipe packed with dry sand, which was compacted in
place.

The pipe was held vertical in the vice and a section of tube was
found so it could be used to slip over the pipe to bend it. The
pipe was then heated with a propane torch at the precise point
where it was going to be bent, ensuring the outside of the bend was
the hottest at the point where it would need to stretch the most.
When red hot, the larger tube was slid over the top and used to
bend the hot pipe to the same profile as the template. This heating
process was repeated a couple of times until the pipe was exactly
the right profile. When cool, the end cap was removed and the sand
was thoroughly cleaned.

Water drain tap

The water drain tap presented a problem as it did not appear
complete, and it took some time to find someone who knew this style
of fitting. Luckily, I noticed a photo of a similar fitting on
SmokStak, and a message to Bryan Storey elicited a very helpful
reply with some detailed photos, not only of the drain fitting but
also of the correct style of cart, which will be covered later.

Brian’s photos showed the drain screw from which a copy was
made, scaling the photos based on the known measurements of my
fitting. To complete the tap, a silicon ring was used for the seal
rather than leather, which would have been originally used.

The only unanswered question concerned a hole in the bottom of
the round part, which I sealed with solder as it had no threads for
a screw plug. To date no one has offered a reason for this hole,
and if any reader knows why and the correct method to seal it
please let me know.

Igniter

The igniter presented a major challenge and the simplest course
would have been to purchase a replacement. Everything was rusted
solid and the main part of the arm, to support the shaft, had been
broken off at some stage. Despite lashings of penetrant, nothing
shifted, and I had to resort to the hacksaw and drill to
disassemble the igniter.

Fortunately, the hole for the shaft was not badly damaged and a
clean up with a reamer was all that was needed. The remains of the
shaft were drilled out from the contact head, which was brazed onto
a new shaft of 7/16-inch drill rod. The holes for the locking pin
and spring retaining pin were only drilled in this shaft when the
other parts were made and trial fitted.

The screw thread at the top of the tapered shaft for the fixed
contact broke off as soon as I tried to move it, and the tapered
Mica sleeve was also badly damaged. While it is possible to wind a
new tapered sleeve using Mica sheet, I decided to take the easy
option and bought a parallel one. While the tapered profile was
copied from the old post, using a parallel mica tube made it
necessary to braze a thin steel disc just under the contact to hold
the mica washers and shaft in place. A new bushing was made to the
size of the new parallel mica tube, to replace the old bushing with
a tapered hole.

A new contact was made from a piece of iron nail, although this
would not last as long as a special tungsten point.

The major problem with the igniter was the lack of a support
arm, but photos and the remains of the original gave me enough
information to fabricate a replacement.

As a first step, the igniter was set up square on the milling
table and the broken area milled true. The new section was to be
shaped from a piece of 1-1/2-by-1/2-inch steel but there was little
margin for error. A thin section of similar profile steel was Super
glued in the required position in the igniter and the long edge set
square to the axis of the mill. The coordinates of the mill were
set to zero at one of the corners of the section of steel before it
was broken off, and 2-1/8-inch diameter holes were drilled in the
remaining stub of the old arm, the measurements from the corner
being noted. The igniter was removed and the steel to be used was
set square and again the coordinates of the same corner set to
zero. Copying the coordinates of the drilled holes, 2-1/2-inch
holes were drilled in the end of this steel, to perfectly match the
holes in the igniter.

After a trial assembly to check the fit was correct, 2-1/8-inch
steel pins and the mating surfaces were covered in flux, the steel
piece was brazed to the igniter.

The tube to support the end of the shaft was turned from a piece
of scrap steel, then using a greased length of 7/16-inch rod to
keep it square with the main hole in the igniter, it was brazed in
position.

Once the support arm was finished, the remaining parts were
fashioned, and the igniter was completed with new springs, mica
washers and fahnstock clip.

All that was needed to finish was to drill the holes in the
moving stem for the pins, and a hole in the end of the new support
arm to tension the end spring. While drilling this latter hole,
several further holes were drilled so it would be possible to
adjust the spring tension at a later date. The igniter was set up
so that the points gap after snapping was between 0.035 to 0.070
inches.

The repaired igniter was tested by connecting it to a battery
and coil and snapping it by hand. After some fine adjustments to
the spring tension, it worked fine.

In part three next issue, Peter puts the finishing touches on
this amazing restoration.

Contact Peter Rooke at: Hardigate House, Hardigate Road,
Cropwell Butler, Notts, England, NG12 3 AH;
peter@engineerpeter.co.uk • www.enginepeter.co.uk

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