[Vwdiesel] Petter diesel genset restoration update (was) "Seeking experience or data on Petter stationary diesels"

[Area31 Research Facility]

James, I should say that the reason equipment ends up in this particular
yard is not necessarily because it is broken.  In my case this genset was
unfortunately left uncovered and too long.  I'm sure now that it was
operational when delivered to the yard.  It still had a third of a tank of
diesel fuel in it.

I got the head off the Petter yesterday and can confirm that the cylinder
has a piston frozen solid at BDC.  Much rust in the bore above the piston.
By rotating the flywheel (it can move now!) The cast steel cylinder sleeve
and head are held on with six long studs protruding up from the block like
the cylinder in a radial aircraft engine.  I pushed the piston and cylinder
sleeve completely out of the top of the block by rotating the crank and
could see into the crankcase.  It looks really good in there.  I am impressd
with the quality and construction of this very heavy dutily built engine.
Some cleaning of the cylinder and piston top revealed a piston part number.
It is standard size.  A bit of rust remover solution cleaned some of the
rust in the bore to reveal clean steel.  The pitting won't be an issue I'm
sure and a simple cleaning with my hone ought to put a useable finish and
crosshatch back on this piece one I getthe piston out.  I set the cylinder
up on hardwood block spacers to the block and tried to press the piston
downwards with a 12 ton hydraulic jack pressing up against a large chain
going around under the engine block.  I applied a LOT of force and even
applied heat but the piston did not budge.  The way I did this I was not
pushing against the con rod.  I had a two foot bar and 30 lb weight on the
fltwheel trying to pull the crank in the correct direction if the piston
moved to assure that I did not stress the bearing.  It is soaking overnight
in the most agressive solvent I have, used as a rust and penetrating agent.
It is a very powerful chemical that has a really noxious smell just like
that dip tank carburetor cleaner.  I'll try again today.

This engine is a Petter PJ1.  813 cc (96.88 mm bore x 110.00mm stroke).and
has direct injection.  Specs are 5 HP @ 1000 RPM, 10 HP @1800 and 11.3 HP @
2000.  The intake and exhaust valves sit flush on a totally flat head
surface facing the piston. Valves are each 40.5mm diameter (about 1-3/4").
The injector is a big bugger, about 7" long.  It's tip just protrudes into
the center top of the combustion chamber between the two valves. The
injector tip is not rusty and was protected with carbon.  The top center of
the aluminum piston has a (~1-1/8" diameter) hole in it which gets larger
and then smaller as you go downwards into the piston.  Imagine the shape of
the volume occupied in a tank of water if you were to depress a golf ball in
about 3/4 of the diameter.  In the bottom center of this spherical
depression is a rising cone terminating like a pin sticking up in the
middle.  I think this may be part of a swirl design and possibly to break up
the injector spray against.

The head gasket is as simple as it gets.  A ring about 1/2" wide and 1/16"
thick.  Like a washer ~ 4" i.d. and 5" o.d.  I can make a replacement myself
from sheet copper if I want to try.

If I am successful in releasing the piston without breaking anything I think
I can get the engine running with just having to purchase a new set of
standard rings and the head gasket.  The valves look great and I can grind
and lap them in myself with the machine tools I have.  The guides have no
play and the valve gear operates smoothly..

I am more than a little impressed with this very neat package!  What a lucky
find.

Rob

----- Original Message -----
From: "James Hansen" <jhsg at sasktel.net>
To: <vwdiesel at vwfans.com>
Sent: Thursday, June 16, 2005 4:52 AM
Subject: RE: [Vwdiesel] Seeking experience or data on Petter stationary
diesels


>
> James,
>
> Thank you for this.  That was also good to point out the prospect of
> damaging the babbit in the lower rod bearing.  I hope I haven't deformed
> that too much already.
> ________________
>
> You're welcome.  It's doubtful that anything is damaged unless a long
> persuader was tied to the flywheel and some serious torque applied.
> Too bad about your thumb.  Be careful out there...
>
> Ten horsepower... that should be perfect for what you want.  That's a
pretty
> nice engine actually, take care of it, it should last many many years.
Try
> to keep in mind you are on a search for why it was in the junkpile too.
> Usually, stuff is there for a reason, like at the time it probably wasn't
> worth fixing, but now you have to figure out why it was there and correct
> that as well, along with restoring it to operation.  The "why was it
there"
> part is half the fun in a restore.
> take care
>
> -James
>
>
> --
> No virus found in this outgoing message.
> Checked by AVG Anti-Virus.
> Version: 7.0.323 / Virus Database: 267.6.7 - Release Date: 6/10/2005
>
> _______________________________________________
> Vwdiesel mailing list
> Vwdiesel at vwfans.com
> http://www.audifans.com/mailman/listinfo/vwdiesel
>