Larry -
Even if you get the same brand they can weigh differently... I've seen it
first hand!
Alan
On 2/10/07, Larry Varley <varley@cosmos.net.au> wrote:
>
> Hi
> As mentioned the key here is the weight.
> The first thing I would do before buying anything is make sure the
> replacement weighs almost the same as the originals, you will be pretty
> lucky if it does. If it turns out to be considerably lighter than the
> originals for instance you may have to remove a lot of metal from all
> the originals, that may not be possible without seriously weakening
> them. Ideally you need a piston of the same brand as the originals.
> Cheers
> Larry
> Austin Healey 100 restoration site
> http://www.acmefluid.com.au/larry/
>
> WILLIAM B LAWRENCE wrote:
> > Well, for one thing the cost of a new set of pistons from Moss is
> > between $350 and $425 (Perhaps you can do better than that.) while
> > most machinists will perform the measurements for nothing and the
> > balancing for about $125 (static and dynamic). The cost of parts for
> > these engines is not trivial, so if the used pieces are not damaged or
> > worn beyond spec. why replace them? I realize that money is not an
> > object for some, but I am not among that fortunate group. I consider
> > it a waste to replace parts just to be able to say they are new. With
> > some exceptions, I have as much confidence in a good used part (It's
> > survived over 50 years already.) as I do in a new one that may be crap
> > out of the box.
> >
> > I know that the common wisdom is that all parts need to be replaced
> > whenever you rebuild an engine, but I've never really been convinced
> > whether that is best practice or just good marketing.
> >
> > Pulling on my asbestos drawers,
> > Bill Lawrence
> >
> >
> >> From: David Nock <healeydoc@sbcglobal.net>
> >> To: WILLIAM B LAWRENCE <ynotink@msn.com>
> >> CC: genski434@comcast.net, healeys@autox.team.net
> >> Subject: Re: Need some help
> >> Date: Fri, 9 Feb 2007 08:25:21 -0800
> >>
> >> If you are going to go tho the effort to have all the pistons out
> >> and inspect and weight them all to match them all up to the used
> >> piston why not just do it right and install a new set. After all the
> >> other used pistons in the engine have been there just as long as the
> >> one that went bad.
> >>
> >>
> >>
> >>
> >> David Nock
> >> British Car Specialists
> >> Stockton Ca 95205
> >> 209-948-8767
> >>
> >> www.britishcarspecialists.com
> >> .
> >> .
> >>
> >> On Feb 8, 2007, at 6:01 PM, WILLIAM B LAWRENCE wrote:
> >>
> >>> I guess I'm just not up for absolutes. And with due respect to
> >>> David's knowledge and experience on the topic, I think the answer
> >>> is that it's a bad idea to mix used pistons unless you can be sure
> >>> that they are all in the same condition (within specification) and
> >>> that they are matched in weight.
> >>>
> >>> If you are going to install used parts (for whatever reason) they
> >>> should be inspected and measured to assure they are within the
> >>> manufacturer's specifications and that they are not damaged in any
> >>> other way (you know, like being cracked) The weight question will
> >>> be addressed by the machinist when he statically balances the
> >>> reciprocating assemblies. A step that should not be left out.
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