Date:         Mon, 6 Sep 2010 21:05:00 -0400
Reply-To:     David Beierl <dbeierl@ATTGLOBAL.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Beierl <dbeierl@ATTGLOBAL.NET>
Subject:      Fwd: Boston Bob on Connecting Rod Bolts
Content-Type: text/plain; charset="us-ascii"; format=flowed

>Date:         Mon, 4 Sep 2006 10:50:11 -0400
>Reply-To:     ROBERT DONALDS <donalds1@VERIZON.NET>
>Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
>From:         ROBERT DONALDS <donalds1@VERIZON.NET>
>Subject:      Re: Connecting Rod Bolts
>Comments: To: Evan Mac Donald <macdonald1987@SBCGLOBAL.NET>
>To:           vanagon@GERRY.VANAGON.COM
>
>Evan
>1.9 and 2.1 rods are the same casting and are interchangeable with the
>exception of the bolt. The longer stroke 2.1 cranks in combination with the
>1.9 rod bolts can but do not always hit the camshaft
>The 2.1 rod bolt work well for 150K and I have seen these stretch to yield
>bolts reused with failing.
>2.1 rods distort over time by this I mean the big end is no longer round.
>The cap shifts and the big end gets smaller opposite the parting line.
>Another way to say that is if you draw a line down the rod from the small
>end threw the beam of the rod threw the big end the circle is smaller at
>that point. So just replacing the bolts is not the cure for the 2.1 rod
>problem. The big end needs to be resized to do this I have a cap grinder it
>trims a few thousandths off of the mating surfaces of both the rod and cap.
>After deburing the hole and installing new non stretch to yield bolts and
>reassembling the rod I torque the nuts and resize the big end with a sunnen
>rod hone. Machine shops have spec books to provide dimensions for the
>finished size.
>I take the next step and that is to install rod bearings torque and measure
>difference between the size of the ID of the big end with the bearing in
>place The size of the rod journal this is clearance to the crankshaft. The
>difference influences the warm oil pressure.
>used rods with the 150K measure as much as .004ths bearing clearance this is
>enough make oil light come on at an idle. My engines have a rod bearing
>clearance of .0015ths. and I can say that because I have invested in the
>right equipment to properly measure clearances and restore dementions.
>
>you CANT just replace the bolts unless you only want 6k out of the engine
>
>my rebuilt rods are $140 exchange with news bolts ready to install
>Rebuilding is about restoring clearances
>assembling is about adding parts
>at Boston engine you get more than parts
>
>Bob Donalds
>Boston Engine
>
>all rights reserved
>
>
>----- Original Message -----
>From: "Evan Mac Donald" <macdonald1987@SBCGLOBAL.NET>
>To: <vanagon@GERRY.VANAGON.COM>
>Sent: Monday, September 04, 2006 8:51 AM
>Subject: Connecting Rod Bolts
>
>
>>I have heard that the bolts for 2.1 l con rods are not the greatest, and
>>should be replaced on a rebuild with 1.9 l bolts. I don't have any 1.9 l
>>engines around I could steal them out of, and would also worry about
>>re-using "tired" bolts in an upgraded rebuild, anyway.
>>  Does any body have any suggestions? I haven't had much luck on my own,
>>but I also have no idea what other bolts may be a usable substitute.