Photos: Kevin Wilson
Project Box Hauler
Part II: Bellows Style Up-Pipe Upgrade
Last month, we introduced our latest project truck, a well-worn, 200,000-plus–mile Ford F-350 fitted with the 7.3L Power Stroke and a six-speed manual transmission. The owner found this dually while scanning the classifieds where it was listed for sale with a 28-foot gooseneck trailer. The combo used to be a Castrol Racing/John Force car hauler that racked up 215,000 miles in regular cross-country jaunts.
Last month, we took his newfound purchase over to the folks at Strictly Diesel in Scottsdale, Ariz., for some routine maintenance, which included fluid and filters changes. They also went over the Super Duty with a fine-toothed comb and found several problems with the truck, which are not uncommon for high-miler diesels. Over the next few issues, we’ll be upgrading this high-mile Ford with a whole host of aftermarket goodies while showing you some tricks specifically for the 7.3L. We’ll also bolt on a few extra goodies to get Project Box Hauler in tiptop shape to be a reliable daily drive and serious towing workhorse.
This month, we’ll address a problem that’s common to every 7.3L Power Stroke ever made: Leaking turbo up pipes. Anyone who’s ever owned a 7.3L knows what we’re talking about—that annoying exhaust leak noise that develops over time, which you can never find no matter how many times your tighten all the exhaust clamps. The issue is the up pipes behind the engine that run from the exhaust manifolds to the back of the turbo.
By design, the factory pipe system uses a slip-joint setup and the old-school donut-style gasket that’s suppose to allow for movement from heat expansion and contraction. Over time, the slip joint tolerances increase and cause exhaust leaks, which can be spotted with soot accumulation around the joint. In some case, the “donut” can actually wear a hole in the pipe from movement, causing an exhaust leak. On our guinea pig, the setup was so bad it had worn a hole on both up pipes. This leakage reduces the amount of exhaust that flows to the turbo, which can drop boost levels significantly.
The fix is actually something International, (the father of the Power Stroke), developed for its agricultural and industrial applications. The company developed a bellow-style up pipe kit that replaces the factory slip-joint setup and provides a solid seal from exhaust leaks while still allowing for the expansion and contraction of the exhaust pipe.
Strictly Diesel in Scottsdale, Ariz., uses this kit exclusively on the 7.3L with excellent results. The kit comes complete with new bellows style up-pipes and a new cast iron Y-setup that merges the pipes into the turbo housing, along with all new bolts and gaskets. The install is a bolt-on deal, but there’s a trick to getting everything to fit right the first time that only seasoned installers know.
Since our dually was destined for an upgraded exhaust system, repairing the leaking stock up pipes was the first order of business since you have to pull off the turbo downpipe anyway on the passenger’s side to get to the up pipe. If you’re opting to do a turbo back on the truck, replacing the up pipes is a great place to start.
Airaid Filter Company
Shell Oil Company