- Joined
- Feb 4, 2013
- Messages
- 28
Following is the text I referred to in message above. Sorry I did not save the source, but many thanks to the author:
I acquired a South Bend shaper notlong ago, and am having oil pump
issues too. Mine was built in 1962, and is in very good overall
shape, but it seems that the oil pump was only working
intermittently. Looking inside the sump, I noticed a lot of plastic
shavings, as though the shaper had once been used on a piece of
nylon, or something. Anyway, these were getting sucked into the
inlet, causing the pump to quit working. I decided to drain and
clean out the sump, and disassemble the pump as much as possible to
try and fix the problem.
After draining the sump, I removed the ram, rocker arm, and related
parts, to gain better access to the pump. I removed the two screws
that hold the pump housing to inside wall of the shaper, but I
wasn't able to figure out how the pump housing comes loose from
the "junction box assembly" (the block with the four oil lines
coming out the top). Seems like the joint would twist a bit, but it
didn't seem like it was threaded. I didn't work it around too much
because I didn't want to break anything, and the oil tubes would
only allow so much maneuvering.
Unlike Dan's machine, mine has all the oil tubes soldered to the top
of the junction block, not just press fitted. The outer ends of the
oil lines serving the bull gear and the crank pin are easily
removed, but the two serving the ram ways are soldered into press-
fit spigots that don't seem very likely to come out quietly. I was
really hoping I could get the pump body separated from the junction
box, but I gave up, and decided to do whatever I could short of
removing the pump.
First I removed the brass plunger. With the pump housing loose from
its mountings, the plunger just pulls straight up and out. Next
there is a return spring for the plunger, which pulls straight out,
and then the steel ball which just rests in the bottom of the hole.
The intake for the pump is directly under where this ball seats. I
found some small plastic chips in this part of the housing, which no
doubt was part of the problem.
The relief valve body screwed out of the housing rather easily, so I
was able to disassemble it on the bench. I removed the adjusting
screw spring and ball from the valve body, and found nothing wrong,
so I just reassembled it.
Next I blew compressed air through all of the pump passages, as best
I could. Since I didn't remove the junction box from the top of the
pump housing, I wasn't able to disassemble the outlet valve, but I
was able to get compressed air through it, and air came out of each
of the four tubes. So, I was reasonably sure that there were no
obstructions in the oil circuit.
Then I reassembled everything. I wound up having to re-solder one of
the ram way oil tubes at ram way spigot, as it must have come loose
from my working the pump around inside the shaper. I refilled the
sump with oil, and tried it out. The pump started up working right
away, and I rejoiced at my success. My joy, however, was short
lived, because I eventually realized that the pump would not start
back up once the machine had not been run for more than several
hours, like overnight. Almost like it "lost its prime" or something.
In order to the pump started back up, I would reach into the sump
with a long stick, and work the plunger up and down rapidly and
vigorously until the pump would start pumping. Then it would work
fine as long as the machine was running, and would start back up
again after being shutdown, as long as it wasn't overnight.
So, now what? I didn't find any problems in going through the pump
(to the extent that I did), though I did notice that the brass
plunger seemed rather worn, and fit rather loosely in its bore. So
my next step will probably be to make a new plunger, and see if that
cures the problem. Like Ed mentioned, mine also has a pretty severe
flat worn on top from the actuator arm. I'm eventually planning a
thorough refurbishment of the entire machine, and at that time I
would like to disassemble the pump more completely. In the meantime,
I can live with it the way it is, I guess.
As for your problem, Chris, it sounds like your plunger spring is
either broken or missing. Or maybe the plunger is jammed in its
bore, perhaps with an errant metal chip. If you can take the pump
loose, you should be able to stick a slender rod up through the
intake hole to try and push the plunger out. Then you should be able
to figure out what the problem is.
Like you, I would still like to know for sure how the junction box
(manifold) is fastened to the top of the pump body. It sure didn't
seem to me like it was threaded. Dan said in his post that he had
the pump out of the machine, but he didn't really say if he
separated the two parts. It seems like mine would twist, but not
unscrew or pull out.
I don't know if any of this helps your situation, Shawn, but let us know how it goes with your efforts.
I acquired a South Bend shaper notlong ago, and am having oil pump
issues too. Mine was built in 1962, and is in very good overall
shape, but it seems that the oil pump was only working
intermittently. Looking inside the sump, I noticed a lot of plastic
shavings, as though the shaper had once been used on a piece of
nylon, or something. Anyway, these were getting sucked into the
inlet, causing the pump to quit working. I decided to drain and
clean out the sump, and disassemble the pump as much as possible to
try and fix the problem.
After draining the sump, I removed the ram, rocker arm, and related
parts, to gain better access to the pump. I removed the two screws
that hold the pump housing to inside wall of the shaper, but I
wasn't able to figure out how the pump housing comes loose from
the "junction box assembly" (the block with the four oil lines
coming out the top). Seems like the joint would twist a bit, but it
didn't seem like it was threaded. I didn't work it around too much
because I didn't want to break anything, and the oil tubes would
only allow so much maneuvering.
Unlike Dan's machine, mine has all the oil tubes soldered to the top
of the junction block, not just press fitted. The outer ends of the
oil lines serving the bull gear and the crank pin are easily
removed, but the two serving the ram ways are soldered into press-
fit spigots that don't seem very likely to come out quietly. I was
really hoping I could get the pump body separated from the junction
box, but I gave up, and decided to do whatever I could short of
removing the pump.
First I removed the brass plunger. With the pump housing loose from
its mountings, the plunger just pulls straight up and out. Next
there is a return spring for the plunger, which pulls straight out,
and then the steel ball which just rests in the bottom of the hole.
The intake for the pump is directly under where this ball seats. I
found some small plastic chips in this part of the housing, which no
doubt was part of the problem.
The relief valve body screwed out of the housing rather easily, so I
was able to disassemble it on the bench. I removed the adjusting
screw spring and ball from the valve body, and found nothing wrong,
so I just reassembled it.
Next I blew compressed air through all of the pump passages, as best
I could. Since I didn't remove the junction box from the top of the
pump housing, I wasn't able to disassemble the outlet valve, but I
was able to get compressed air through it, and air came out of each
of the four tubes. So, I was reasonably sure that there were no
obstructions in the oil circuit.
Then I reassembled everything. I wound up having to re-solder one of
the ram way oil tubes at ram way spigot, as it must have come loose
from my working the pump around inside the shaper. I refilled the
sump with oil, and tried it out. The pump started up working right
away, and I rejoiced at my success. My joy, however, was short
lived, because I eventually realized that the pump would not start
back up once the machine had not been run for more than several
hours, like overnight. Almost like it "lost its prime" or something.
In order to the pump started back up, I would reach into the sump
with a long stick, and work the plunger up and down rapidly and
vigorously until the pump would start pumping. Then it would work
fine as long as the machine was running, and would start back up
again after being shutdown, as long as it wasn't overnight.
So, now what? I didn't find any problems in going through the pump
(to the extent that I did), though I did notice that the brass
plunger seemed rather worn, and fit rather loosely in its bore. So
my next step will probably be to make a new plunger, and see if that
cures the problem. Like Ed mentioned, mine also has a pretty severe
flat worn on top from the actuator arm. I'm eventually planning a
thorough refurbishment of the entire machine, and at that time I
would like to disassemble the pump more completely. In the meantime,
I can live with it the way it is, I guess.
As for your problem, Chris, it sounds like your plunger spring is
either broken or missing. Or maybe the plunger is jammed in its
bore, perhaps with an errant metal chip. If you can take the pump
loose, you should be able to stick a slender rod up through the
intake hole to try and push the plunger out. Then you should be able
to figure out what the problem is.
Like you, I would still like to know for sure how the junction box
(manifold) is fastened to the top of the pump body. It sure didn't
seem to me like it was threaded. Dan said in his post that he had
the pump out of the machine, but he didn't really say if he
separated the two parts. It seems like mine would twist, but not
unscrew or pull out.
I don't know if any of this helps your situation, Shawn, but let us know how it goes with your efforts.
