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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