B275 diesel

Hi folks

I have a diesel leak in this engine and it's from the "injection pump drain pigtail" it's not leaking all the time just once in a while it squirts diesel onto the ground. can someone explain what's happening and how to remedy it?

Is it an older B-275 with the air-governor and in-
line CAV pump? I've got two like that and both
spit oil or diesel out that pigtail. Done it for
20 years now and never bothered a thing.

The in-line pump is supposed to be kept full of
motor oil. When the diesel pump plungers leak a
bit internally, the pump's crankcase gets
overfilled and the excess comes out that little
pigtail. I drain mine once in awhile and fill
back with motor oil. Been fine.

If you really want to fix perfect - I know a place
in England that still sells new pump plungers and
pistons. Big waste of money though as I see it if
the tractor still runs OK.

Boy.. I really ought to get into the manuals for this machine. Are parts like this hard to get? I mean if I was to try tpkeep it running reliably and use it.

Its 1960 model and I don't know what it has for a governer. It does have trouble settling on an idle speed anywhere near mid throttle, and cold start isn't easy. Other than that it works ok.

All the early ones are bad cold starters. Put
some "fast heat" Mercedes car type glow plugs in
it and it will start like a new tractor (big
difference). A cheap and easy fix. Mercedes 190D
car had the same awful glow plugs and system as
the B275 - so Mercedes and Bosch came up with a
nice upgrade for the system.

Early B275 diesels use model DES CAV inline
injection pumps with a air throttle and air
governor. There's a butterly valve in the air
intake manifold that is hooked via an air-line
to the back of the injection pump (big air
diaphram inside there). The "pump" is basically a
box with an oil sump, five lobe camshaft, and four
separate plunger injection-pumps riding on top.
Also has a fuel transfer pump bolted to the side
of it.
I have two 1960s with that air-governor setup.
Newest one is serial # 16195.

I also have a 1961 B275 (#31537) and that has the
more coventional rotary CAV distributor pump with
a centrifugal governor.

Last time I checked parts prices (in England) for
a full inline rebuild, it is as thus:

4pcs Element 7033-462H @ £15.00 each..............
£60.00 Spaco 2076
4pcs D valve 7033-359 @ £6.50 each................
£26.00 Spaco 2044 Delphi 92244
4pcs D valve seal. 5936-22 @1.50
each.....................£6.00 Spaco 1573
4pcs D valve Holder 7032-3 @
£10.50.......................£42.00 Spaco 1913
Carriage..........................................
...................................£8.50
Total
Invoice...........................................
.........................£142.50
We also have the governor diaphragm @ £20.00 if
required
[email protected]

Hi jdemaris, nice to find sombody who knows about CAV in line pumps on IH B250 & B275 tractors. The first 440 B250s built had the CAV inline pump with mecanicle govenors. I have B250 S/N 549 making it the 49th made as you will know all IH tractors started at S/N 501. My pump leaks out this pipe and after taking it to our local pump spealist he told me the plungers were OK but the plunger on the side mounted lift pump was worn. I am very mutch into the little IH Bradford tractors and I am restoring a 1961 B414 at the moment.Hope we can help one another in the future. MJ.

You think this unsettled idle is a result of a worn injector pump instead of the governor?

I had suspected the side-mounted fuel transfer pump at one time. But after I removed it completely and installed an electric pump - the problem was still there. From what I"ve seen, it"s normal for the four injector pump plungers to leak a little and dribble fuel inside the pump box. They just get worse with time and age. Doesn"t seem to have any effect on how the tractor starts or runs unless they get real bad.

I'll put a little container on there to catch the diesel that drips out.

Any ideas on the engine idle problem though ?

Without hearing it - it's hard to even guess. Like
any internal combustion engine with multiple
cylinders - rough idle can be from one of the
cylinders not firing the same as the rest, or an
overall problem with all four at once.

With a diesel - with an inline injection pump -
there is a separate injection pump for each
cylinder. So, one bad fuel injector pump can make
one cylinder weak, skip, or whatever and cause a
rough idle. A diesel with a rotary pump cannot
suffer that same problem except in extreme rare
cases (scratched head & rotor or a bad delivery
valve in a CAV rotary).

Seems you need to ascertain if it's an overall
"running rough" or just one cylinder skipping.

With your tractor and the in-line pump-box with
four pumps in it - there's not much that can make
all four cylinders run rough at idle and smooth
out at higher RPMs. Very worn injector nozzles
will often leak and dribble at low speeds and work
better at high. So, could be a worn-out nozzle.
Could also be valve adjustment.

You can try cracking an injector line loose (at
the injector), one at a time with the engine
idling and see if any specific one makes less
difference then the rest. That would indicate one
cylinder skipping.

The injector pumps could also be out of
adjustment. All four has an adjuster on them to
set fuel delivery. I've done a few with crude
tools.

Also - on the B275 - there are moving mechanical
parts in the air-intake manifold along with a
diaphram in the back of the pump box that can go
bad and make the whole thing run lousy. One year
- one of my 1960 B275s ran lousy and I found a
mud-wasp nest inside the air intake manifold
blocking the governor butterfly valve. The next
year - they did it AGAIN. finally put a fine
screen over the air-intake to keep the little
b*stards out.

Like I said, hard to guess without hearing it.
I've come across many lousy running B275s and most
needed engine rebuilds due to too much ether being
used to start them. Luckily, parts are cheap and
easy to get. Last one I rebuilt- the pistons,
rings and cylinders came from this Website.

Not so much rough Idle as not settling on an idle speed.as if someone was opening and closing the throttle.

Sounds like worn parts in the air governor. That
includes metal parts and also the leather air
diaphram in the back of the injection pump. Lots
of stuff to check. There is a butterfly valve
inside the air intake manifold that must move
freely and not be excessively loose. Also - the
air-lines must be clear and intact that hook the
back of the injection pump where that big diaphram
is. The setup is similar to what was used on sold
Fordson diesels. I've never had a diaphram go bad
yet - but I know the new ones are still available.