Date:         Mon, 27 Dec 2004 16:11:49 -0600
Reply-To:     Jim Felder <felder@KNOLOGY.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Jim Felder <felder@KNOLOGY.NET>
Subject:      Reconditioned rods-necessary for diesel, too?
In-Reply-To:  <41CFB90E.900@mchsi.com>
Content-Type: text/plain; charset=US-ASCII; format=flowed

On Dec 27, 2004, at 1:26 AM, Al and Sue Brase wrote:

> Jim:
> Many years ago, I worked in an automotive machine shop that
> specialized in high performance work. Most engines need their rods
> rebuilt to stay alive at higher outputs and engine speeds.
> We used Sunnen precision honing equipment. One needs to push out the
> old bolts; use the cap grinder to take off a slight amount off the cap
> and rod at the parting line; reassemble and retorque to spec with new
> bolts; then put it on the precision honing mandrel and gradually bring
> it up to the minimum ID spec size, while checking the size with the
> bore gauge.

Yep, I got the concept now. Bob D. Explained it pretty well also. I
have a machinist's background (long time ago) but was unfamiliar with
the operation. It does stand to reason that a "work-tempered" rod with
a renewed big-end hole would be better than a new rod.

Is this operation necessary on all waterboxer rebuilds, or only those
who measure out of spec? Is it recommended to do this to the 1.6 diesel
rods as well?

Jim

> It's been a long time since I did this, but it seems like it took at
> least 1/2 hr per rod back then. Maybe one could get faster if he did a
> lot of them.
> Perhaps there are other methods as well. The hone left a beautiful
> finish, much nicer than new. Perhaps other methods might  be faster
> and cheaper.
> 4 rods times 1/2 hr is 2 hr. Two hrs shop time might be anywhere from
> $100 to $160. Plus the bolts.(Above and beyond this, you should get
> them balanced as a set, that is, the big end weights should match and
> the small end weights should match) This might cost another $10 to $20
> each.
> Or go buy the machine.
> Oh, by the way, brand new rods never checked out perfect. Used rods
> that were reconditioned and then run for a while were much better than
> new rods after the same use. Apparently, after stretching, the metal
> was much stronger and held tolerance better.
> So I have always had rods reconditioned on any rebuilds that would be
> pushed very hard. That means any VW engine in a type 2 or Vanagon.
> Al Brase
>
> Jim Felder wrote:
>
>>> You do know you cant reuse the con rods without replacing the
>>> bolts and resizing the big end of the rod
>>>
>>>
>> Some of us didn't know. What is involved in resizing the big-end?
>>
>>
>> Jim
>>
>
>