Well Im off on another build and as usual the issue of a craked main bolt hole comes right in my face as soon as I get the engine apart.
The Lock and Stitch company markets an insert that has a reverse hook thread that screws into the hole after slightly drilling it out and tapping it.
The insert is solid and when the torque is applied the threads actually pull the material together instead of trying to wedge it apart.
The spreading forces on the 12mm main bolts is terrific and its no wonder that the cracks just continue to spread over time.
I spent a fair amount of time this morning chatting with the folks at Lock and Stitch corp and have decided to purchase the tooling to do the 6.2/6.5 main bolts holes.
With all considered I should be able to offer a repaired hole for about $30 each.
Now this is figured on a clean block that I can get around without getting filthy and also one that I can get my Mag drill onto without needing to scrape off a foot of silicone and dirt
There is one shop in PDX that does this but only on their rebuilt engines and not as a service out the door.
I have already put the word out of the upcoming service and have several 6.5 blocks waiting for a date with me.
One fellow wants all 6 outers done as a precautionary measure.
This system is being used on some pretty large equipment and I have spoken with a tech at the local CAT shop and they have used this on large engines with cracks in castings and are very pleased with the results.
WE shall see.
The tooling is available with inserts and such specifically for the 6.2/6.5 mainline 12MM and 10MM holes
best
Robyn