Perkins P6 Marine engine
Esben Beck
Late last year, I bought a 29' 1960 vintage Furuholmen (Norwegian)
Plattgatter with a Perkins P6 engine (1957 or '58 model). The previous owner
bought the engine second hand, and had it overhauled at an (I've been told)
acknowledged marine engine workshop. All bearings (crank shaft, connecting
rods etc.) were measured, but as there was no detectable wear, they were not
replaced. The engine got a good internal clean-up (salt water cooled), new
piston rings, cyl. head seal and other small wear parts such as o-rings,
washers etc. But no attention was paid to the diesel injection pump.
Eventually, the previous owner got the engine installed. Only to discover
that only two cylinders were receiving any diesel. The pump was delivered to
a workshop specializing in diesel engine repair. They could not fix it. The
explaination he got was that the wear was so severe they could give no
guarantee of function. The only detailed statement he recalls was that the
"pistons is not returning to their lower position". The previous owner was
so fed up by now (hundreds of hours restoring the rest of the boat) he had
had it, and he sold it to me.
I knew the diesel pump story when I bought the boat (it was still a bargain,
engine or not). I received the disassembeled injection pump in a box.
And now, as the spring has arrived, I'm ready to get my hands dirty. I'll
try to explain the current situation (this is my first experience with a
diesel engine, so as the terms used are guesswork, I might get some of them
wrong):
The injector "pistons" themselves seems nice. These small pistons forms an
almost air-tight seal against the small cylinders. They are all shiny and
free of visible wear. From what I can see, these small cylinders have two
functions; both to act as high pressure pumps, and at the same time act as
valves, rotated by a pinion meshing with a built-in rack inside the pump. If
these parts should have any visible wear, I would expect helical traces.
Further down the pump, it looks like things are getting worse. The small
"intermediate" pistons (in lack of a better term) with cam rollers, that
travels inside bores machined directly in the aluminium casting, has
significant wear. They are quite sloppy (estimated 5-10 / 100mm when fully
inserted) Could they be the source of the problem?
There is a small aluminium sign on the pump, but it's not possible to read
anything from it. I found no serial number on the engine, just these two
casting numbers:
C0280016 (on engine block, close to starter engine)
0440040 (on the flywheel cover)
So, what to do next? Is it possible to get a new or rebuilt pump, or should
I give this one a try? As I told you, I've never laid my hands on a diesel
pump before, but I do have a well equipped metal workshop, including a
universal I/O cylindrical grinder, and I make my living from engineering
prototype instruments and precision components. My idea is to grind down the
pistons (the ones with cam rollers) until I get a uniform surface, bore out
the aluminium castings, inserting sleeves (with the correct thermal
properties) instead. However, this makes no sense if the problem could be
somewhere else. If you need more info to help me out, please let me know.
All conclutions in this mail is based on what I saw at first glance today.
Other tips and tricks on this engine is welcome. As the boat is constructed
for this particular engine, it would be nice to keep it. Makes the whole
project more complete.
Furthermore, I would like to pay a shitload of money for a P6 manual with
exploded wievs. I don't even know the piston displacement (I guess it's a
354).
Best regards,
Esben, Norway
Tom
Before you do anything more, examine the camshaft of the
pump, if the lobs are worn, you would be better off looking
for another injector pump.
Tom
M/shop info & old machine tools.
http://shopswarf.orcon.net.nz
Esben Beck
"Tom" <tma...@xtra.co.nz> wrote in message
news:3CB4AEBA...@xtra.co.nz...
>>
> Before you do anything more, examine the camshaft of the
> pump, if the lobs are worn, you would be better off looking
> for another injector pump.
>
> Tom
>
> M/shop info & old machine tools.
> http://shopswarf.orcon.net.nz
It turns out two one of the lobs has 2-3 pinhole-sized dents (looks like
erotion) at their summits, estimated 0.05-0.1 mm deep. They do not cover the
whole whith of the lobs. The rollers looks fine.
I also discovered that it will be hard to enter a proper boring tool into
the worn cylinders in the aluminium casting. An alternative would be to use
an adjustable reamer or hone to clear out the bores, and make new matching
cylinders from scratch.
Thanks,
Esben
Tom
If that is the case, you need to look further for why the
pump was only servicing 2 injectors. Perhaps you should
get the pumping elements examined by a specialist..
Kim Siddorn
Has anyone checked the pipework? I sweated blood over a carb bank on a
Honda 400/4 once, only to find that the little nylon block that
connected No1 to No2 had no hole in it from new.
Never assume anything ...........
Regards,
KIm
--
Posted via Mailgate.ORG Server - http://www.Mailgate.ORG
Peter Forbes - Prepair Ltd, Luton, UK
The pump elements are more or less self-contained, and do not actually
move in the pump body, only the element plunger moves up and down, and
that is inside the elemnt itself.
I had a look through the CAV app's book this morning to see what info we
hold, and there is a whole page of Perkins P types, including four or
five variants of the P6, including the P6M.
I have made a list of the elements, and will have a dig through the
stocks of stuff to see if we have any. Will also ask Vince about any
other available pump and injector spares that he may have.
Peter
--
Peter
Peter Forbes
Prepair Ltd
Luton, UK
email: pre...@easynet.co.uk
home: die...@easynet.co.uk
Esben Beck
> move in the pump body, only the element plunger moves up and down, and
> that is inside the elemnt itself.
Yes, the pump elements (learned a new term here) seems to be a very close
fit in the pump body, and they definently won't move once properly
assembled. But below each element plunger, there are spring loaded pistons
riding against the camshaft. These pistons move in the aluminium pump body,
and they seem quite sloppy in my opinion. I would not expect the tolerances
to be as tight here as inside the pump elements, but I figured they might
jam, leaving the pump elements stuck in the upper position. But then again,
this would be very unlikely to happen on four out of six cylinders at the
same time.
> I had a look through the CAV app's book this morning to see what info we
> hold, and there is a whole page of Perkins P types, including four or
> five variants of the P6, including the P6M.
>
> I have made a list of the elements, and will have a dig through the
> stocks of stuff to see if we have any. Will also ask Vince about any
> other available pump and injector spares that he may have.
> Peter
I really appreciate the help I'm getting here.
Thanks,
Esben
Esben Beck
After treating the identity plate on the pump with Autosol and 1200 grit
paper, placing a light source at a special angle and wearing a watchmakers
eyeglass (12x), I managed to identify some numbers from it. It looks
something like this:
------------------------------------
6 2 3 7
o R 5 3 0 5 E o
------------------------------------
(the small o's represents the rivets)
Maybe Discovery Channel would be interested in making a program about the
process. Shure felt like a Forensic Detective.
So, if anybody has one of these around, I'd be more than happy to make a
deal.
Regards, Esben
Tom
Well if it were mine, I'd get one of the later Bosch pumps from
a similar sized engine, get it calibrated to the CAV specs and fit it.
You appear to have the necessary machinery to make the adaptation.
If you were a bit closer, I'd give you one.
Peter A Forbes
The correct and full numbers are:-
BPE6A60Q310S6237 Pump
BEPMZ80A99 Governor
BZKG31-531-538 Coupling
BKB50S87 Nozzle Holder (Injector Body)
BDL110S6133 Nozzle 120atms pressure setting
BFPK22N1 Feed Pump
BFPUE2-54Z Primer
BFJFJ1-501 Pre-filter
BEPK50-50-77 Venturi
BFA5P1 Filter
Peter
--
Peter & Rita Forbes
die...@easynet.co.uk
Lister Cold-Starting Diesel info:
http://www.oldengine.org/members/diesel
Ray Hooley's Ruston-Hornsby info:-
http://www.oldengine.org/members/ruston