John Bouchard came up with a fix that uses good old-fashioned American ingenuity and homemade tools to permanently repair the threads without having to remove the crankshaft. Combine that with a torque-to-yield bolt on a keyless crankshaft, and it's easy to see why broken crank threads are becoming a common problem. The damper bolt is long and thread engagement is at the back of the bore, rather than at the front, so thread engagement is minimal from the factory. He got on the horn with Comp Cams and spec'd out a complete valvetrain designed to pull an estimated extra horsepower out of this already stout engine.įirst, we needed to repair the threads in the crank snout, because left like it is, reassembly is impossible. We've taped the new timing cover seal to keep shavings out of the engine. He drilled approximately 5 inches in, stopping when he felt the bit reach solid metal. We checked our progress often, and stopped when we hit the top of the threads. The first step in the repair is to enlarge the bolt hole with a inch drill bit, making room for the larger shoulder of the new threaded insert tool. Bouchard uses a modified TrimeSert kit from Silver Seal, a thread-repair system that is many times stronger than a Helicoil and will withstand the lb-ft balancer bolt torque spec. Eliminating the variable-valve timing simplifies the engine management and allows for a more aggressive cam profile. This is followed by the double roller timing set, modified oil pump drainback, and a non-VVT timing cover. Using it, a regular three-jaw puller is all that's needed to quickly remove the damper-not a specialized tool. With the shoulder of the bolts ground, we can use it to push against the crank snout and the balancer will slip off past it. Using our Eastwood belt sander, Bouchard grinds the shoulder off the bolt, making it a smaller diameter than the ID of the damper. Using the witness mark on the mating surface, Bouchard traces a guide to grind down the bolt for its new job in removing the lower pulley. We didn't throw it away just yet, though. You'll obviously have to replace the bolt since they're torque-to-yield one-time use only design. It is so bad in our case that the bolt turns freely in the crankshaft snout. The metal shavings are clear evidence of damaged threads. But while we do this cam swap, we've got to address the bigger problem: stripped crankshaft threads. Here's what Comp sent us: a roller cam, a double roller timing set, captured roller bearing rocker arm trunions, dual springs, new pushrods, and a case of break-in oil to seat all the mating surfaces. Now, it was our task to either fix the crank or tear the engine down and replace it. We talked them into selling the long-block to us with no warranty or guarantees and scored this fresh engine for a very low price. An overzealous disassembler stripped out the lower crank bolt while tearing the truck down, so the engine was going to be parted out. They've been standard equipment in Chevrolet and GMC trucks sinceso there are thousands available. Hope this helps solve some mystery about the Stout crank.The six-bolt main block is stronger, but it's 70 pounds heavier than a comparable aluminum block. The chainring bolts to the inside of the right crank arm so remove the arm, replace the chainring. If you ever want to replace the Stout's steel chainring, it is also easy. By the way, the right crank arm mounts on the axle with a huge spline makes the ISIS spline look whimpy. He said no, in this price range the Stout is best value and excellent crank. Since I was getting a new crank, I asked the Specialized/Trek dealer if there was a better crank to install. To my surprise the dealer informed me that Specialized recalled some 2018 Fuse's because of right crank arm failures. I only know because I bought a used Fuse and called dealer to ask about it. Why is this information so hard to find anywhere on line. As you do this the crank bolt will push into the dust cap and extract the crank arm. insert a 8mm allen wrench thru the dust cap, into the crank axle bolt. This is a reverse threaded cap, so tighten-left.Ģ. Just learned that this is a self extracting crank no tools needed. Pulling a Stout Crank right arm on Specialized Fuse Comp, is not done by bashing, and not with a Park tool.