Technique to install rod bolts in end caps
 

I want to know how much effort it takes to install rod bolts into
end caps. I had six bolts from one package that were relatively
easy, and six from another package that do not seem to fit. It's
been recommended that I use assembly lube on them and then
pound them in with a brass hammer. My gut feeling is that the
bolts are the wrong size by a few hundredths of a mm, and I
don't want to wreck a 200 dollar connecting rod to make that
point. However, if I need to hold the end cap in one hand, and
take five minutes to pound it in with the brass hammer, I can do
that, which begs the question, why not press it in with my 20 ton
press (that really sounds wrong.)

I need some help here.

Use a micrometer to measure the shank on the bolts that did fit and compare it to the ones that didn't.

That will at least tell you if your rod bolts are correct.

I did that last week.

http://forums.pelicanparts.com/911-engine-rebuilding-forum/877193-rod-bolt-clearance-problem.html

Comparing the lower numbers yields and interferance of .0007 you could tap this in with a plastic mallet, but using the largest to the smallest in numbers results in .0019 nearly two thousands.
You will damage the rod with that interference let alone have to push it in with a press and it will never stretch coreectly. Unfortunatley this is soomewhat common now days with QC you can try to clean up the bolt bore on the rod or go back to where you bought the bolts with a Micrometer but don't expect anyone you bought them from to know or be able to measure anything.

regards

I bought the second set of rod bolts from a competent Porsche machine
shop. I've been in contact with the owner, who suggested the brass
hammer, and he also said that if I was having difficulty to send the bolts
and rods to him. After more play with the rods and bolts, I've decided
to send them to him for inspection and hopefully installation.

I'm thinking that he'll have the same trouble that I had. One way or
another I'll get bolts that fit my rods. Hopefully I can get this put together
before the snows fly here in Michigan and I'm shut out of my garage for
five months.

It's time to report back: The rod bolts are in the end caps, and
the remaining three rods are on the crankshaft :) :)

My Machinist told me that there was a run of rod bolts that were
a bit looser than what had come from Porsche. Evidently I
stumbled across a few sets of these over the years, and I was
not willing to hammer the living $hit out of my current bolts to
try to get them into the caps... It was worth it to me to have
that job delivered to a pro that knew what to feel for and how
hard to smack. He said that they are a tight fit, like a shuffle
pin.

In a day or two, I'll drop the crank into the case and seal it up.
I hope to have a fireup before the snow flies.