Hi there David and Keith,
Coincidentally in the last few days I have pressed off about 40
pistons from the rods.
I'm building, blueprinting and tuning a 3.5 ltr Rover engine.
Of the 40 pistons, all 10,5 cr only about 13 are reusable.
The rest had worn out topringgrooves.
Last Friday I got another nice set of 10,5 pistons but the mechanic who
took them out of the block
had thrown the big-end caps away so I have to press the rods in and out.
Now as I had heard a lot of horrorstories of broken pistons during
hydraulic pressing
I have done the following.
Took a piece of high tensile rod (M12) and 4 nuts.
The nuts are slightly smaller then the outside diameter of the pin.
A piece of thickwall pipe with an internal diameter of 14 mm.
Now I heat the rod up to about 300 degrees C (572 F)with an adjustable
electric heat gun.
Put the piston/rod assembly in a vice with protected jaws.
Heating the rods with an open propane flame is making the rod too hot.
Temperature should stay well below 1200 Fahrenheit (650 C).
The heating makes all the difference in the initial shifting of the pin.
So I slowly and progressively turn the nut and so press the pin in or
out.
It is a bit more work but safer for the pistons.
If any of you is interested I made a picture of this contraption which I
will
happily send to your private emailaddress.
Lex.
Holland.
-----Oorspronkelijk bericht-----
Van: David Kernberger [mailto:dkern@napanet.net]
Verzonden: donderdag 17 februari 2000 3:20
Aan: Keith Wheeler
CC: mgb-v8@autox.team.net; buick-rover-v8@autox.team.net;
dkern@daffy.napanet.net
Onderwerp: Pressing pistons off con-rods
2/16/00
Keith,
Yes, it is OK to press out the pins yourself, as long as you are
very careful to support the piston solidly in the area immediatley
around
the pin bore. You want all the force to be concentrated right there!
You
can make a support like a piece of thick-wall pipe with a bore larger
than
the pin and an outside diameter small enough to clear the ring area
above
and the skirt area below.
I might be interested in talking to you about the pistons (are
those the parts you are getting rid of?) especially if the price is
right.
How about the rods? Are you getting rid of any of them?
Cheers,
Dave K.
**************************************
>Ok, I've always taken *everything* to the machine shop. I've got
>a bunch of Rover con-rod assemblies sitting about, and I'm trying
>to get rid of stuff I don't want/won't use. If I make a jig for
>my benchtop hydraulic press, will I screw up anything if I press
>the pistons off of these con-rods myself?
>
>Also, here's the current saga:
>
>Disassembled one of my 3.5s, oil control rings were gone, and on a
>couple of pistons the lower compression ring was so coked up they
>had siezed. Yuck. Scratched bores. I'm going to have it taken out
>020, go with higher compression pistons, and it goes in the 'B. I've
>decided that my 3.9 (which only needs rings, bearings, and a camshaft,
>no machine work) will go in my Range Rover.
>
>Hope everyone's projects are rolling along,
>
>-Keith Wheeler
>Team Sanctuary http://www.TeamSanctuary.com/
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