Kas,
Thanks for the great information. My machinist called Carillo, the rod
bolts I found in this engine are the best Carillo makes, their torque chart
says the bolt can 100 ft lbs of torque. We were a bit leary of the stock
rod taking that kind of torque, so the shop tested the bolt in the rod. At
80 there was no stretch at all. At 90, they measured .006 stretch, so I am
going to torque them at 90 ft lbs. The machinist gave me a packet of
special grease to use on the threads, as a bolt that size under that much
torque will not torque up properly due to the friction on the threads using
regular oil.
No wonder one of these bolts was loose when I tore down the engine. There
is no way the other 7 bolts that were still under torque were even close to
90 ft lbs.
The machinist also agreed with your initial run in procedure, almost to the
letter. I always thought you ran in a cam and tappets at about 2500 for 20
minutes. His explanation was that is too fast, it will bring up the
temperature on the tappets and cam lobes too quickly, and will effect the
hardening on the cam and tappets as they are seating. He also emphasized
1500 rpm's and NO BLIPPING THE THROTTLE. I wonder why I never read this
before. Now I'm curious about those engines I did not follow this advice on!
So, assuming all goes to plan I should have this engine back in the car
tomorrow. I think I'll be pretty much broken in by the time I make it from
Connecticut to California to pick you up! Especially after trying to
outrun a few Police Cruisers after they see an unmuffled yellow streak go
by! Where are we going? ;-)
In all seriousness, thanks again for all your help. Your involvement here
means a lot of all of us!
At 09:22 AM 3/21/00 -0800, R. Kastner wrote:
>I have had a lot of experience with loose con rod bolts in the early days
>of Triumph engine modification. You were just a very short step from having
>that rod out the side of the block. The fretting you see on the surfaces of
>the rod are from the cap MOVING around due to the clamping not being high
>enough. I went to larger ( in your case Carillo) rod bolts that were very
>hard and therefore did not stretch, then increasing the torque to 60 pounds
>instead of 45. When I did this I first took a small amount off each side of
>the rod surfaces, then drilled out and tapped for the larger bolt, then
>tightened to the new torque value, then had the rod bored to the stock
>diameter to make it round again. When after this everything stayed togeather
>and never had another loose bolt or block ruined becuase of rod cap comming
>loose. On the break-in of the new engine my suggestion and the method I
>follwed is as follows: Bring up the oil pressure by removing the distributor
>and bringing up the oil pressure by spinning the oil pump with a speed
>handle until the oil was fully circulated, replace the distributor, set the
>timing staticly, then fire up and hold the idle steady to 1500 RPM DO NOT
>BLIP THE THROTTLE DURING THE TIME. Keep this idle speed for about three
>minutes, reduce the speed to normal idle for a couple minutes. Shut off
>check for leaks etc, fire up and do the same thing again, DO NOT BLIP THE
>THROTTLE. after a couple minutes more of high idle you ready for a drive. I
>figured about ten minutes of driving was either going to seat the rings or
>scuff them. They always seated. I set the revs to under 4000 durinmg this
>period. After that come and get me. The blippingthe throttle on first start
>by the way is the quickest way in the world to scrore the camshaft and the
>cam followers. But that is only how I did it....."your mileage may differ"
>Kas
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