Harley Cam Chain Tensioner Failure

Let's take a moment and take a look at what's been kind of the Achilles heel, if you want to call it, of the twin cam engine. That's going to be the adjuster shoes on the cam chains inside the cam compartment. In order to access the cam compartment, we're first gonna remove the front exhaust pipe then remove the mid-shift brake control. I'll then remove the cam cover, which we can do with the top end of the engine still intact. Again, we're just doing an inspection. We're not doing shoe replacement. I'm gonna start by loosening and removing the half inch bolts that retain the front pipe to the exhaust bracket. As with all hardware you take off, make sure you set it aside in the order that you removed it. I can then move upward to the half-inch nuts that retain the front exhaust pipe to the cylinder head. I'll remove the upper one, and I'll remove the lower nut that retains the flange to the cylinder head. I'm gonna set my hardware aside. On the Dyna model, there is a center bolt that holds the center portion of the front exhaust pipe to a lower bracket underneath the cam cover. Due to the heat from the pipe and the engine, a lot of road debris, and naturally condensation line depending on storage, most of these bolts have a tendency to rust and freeze in place. Loctite now offers a nice product. It's called Freeze & Release for bolts that are locked in place, whether it be from corrosion or excessive heat. Always safety first. I can use a nice blast of the Freeze & Release product. And then I should be able to get it loose without much problem. Again, when you're dealing with a corroded or a locked in fastener, a good idea is to try and tighten it a little more to snap the thread loose from the corrosion and then loosen it. A lot of times you'll find that'll work very well. It will not only save the bolt, which unless you have a large assortment of hardware on hand you'll want to try to reuse, but it can save you from physically breaking the bolt and busting a knuckle or scarring up some chrome or paint. Set your hardware aside. At this point, the exhaust is loose. Always work with an extra set of hands. It's a good idea. Again, a quick note, each model has a different exhaust configuration. Remove what you need to remove to expose the cam cover. These pedals are in my way. I'm sure if I wanted to, I could work around them. I think it's easier for practical purposes just to remove them and let them lay down out of the way on a clean towel. Again, know where your hardware comes from. Know where it's gonna go back in. If you're not really confident, take a moment, thread 'em right back into the same holes. You know where they came from and where they're gonna go back into when you re-install the mid control break arm. Again, I want to reiterate, we're only removing the cam cover for a shoe inspection, a chain inspection. We're not doing a replacement. That is a very detailed job. It's something should be done by a dealer or a professional. This is more peace of mind to know where the wear factor on your shoes and chains are. I can start by loosening all my cam cover hardware. Again, use a cross pattern. You don't want to just loosen one bolt all the way, and put the preload of all the torqued bolts on one side of the cover or the other. Your service manual, again, is a great resource. Take a moment and read through this section thoroughly before starting any of this procedure. Once I've got all my bolts loosened, I want to bring in a clean drain pan. This is an area it's critical to use a clean drain pan. There is debris when the shoes wear that lands to the bottom of the cam cover. You want to make sure you capture that and you're able to inspect it when you inspect the shoes and the chains I can then start to remove each cam cover bolt one at a time. Once I've got all the bolts except one removed, I can hold onto the cam cover. Remove the last bolt. In this particular application, all the bolts are the same length. But make sure wherever you're working on your motorcycle, if there is different length bolts to lay them out accordingly where they were removed from. If you have to mark with a marker or a piece of tape, do whatever makes you feel comfortable so you're confident when you reinstall the bolts the hardware, the cover back onto the motorcycle that things are in their correct order. You can gently pull the cover away from the engine. Now, some of the early twin cams still used a cam position sensor. Your cover would have a wire entering the bottom of the cover here. And you would not be able to take the cover completely away from the motorcycle. You'll note, there's a little residual fluid. Let it drip out. The gasket that's on the cover will be removed and discarded. You will always use a new gasket. I'll have Mark take the cover and set it aside in a safe place. He can actually remove the gasket, clean the gasket surface. He'll prep the surface with a little High Tack and put a new gasket against it before I go to re-install it. With the cam cover removed, you can wipe around a little bit. Now's a good time to use your handheld flashlight. You can look at the chain and the adjuster's shoe. Specification on these shoes are in your service manual. They're either 90/1000 of wear or if the shoe is more than half worn. Although the outer shoe seems very accessible. The rear shoe or the inner-most chain adjuster shoe is not that visible. In order to access and replace the wear items in the twin cam cam compartment, you would have to remove the fuel tank, remove the rocker boxes in order to unload the valve train and release the pressure on the cams and the chains. You would need a handful of specialty tools, including bearing pullers, which of course if you're gonna replace tensioner shoes and chains, you would replace all the bearings involved in the twin cam mechanism. Before I re-install the cam cover, after a good thorough inspection and cleaning in the compartment area, I want to make sure I clean all my cam hardware. A little Loctite Klean N' Prime. And I want to prep them with a little Loctite blue. I'll do this for all the hardware that retains the cover. Mark's cleaned the outer cam cover. He's installed a new gasket for me with just a touch of Loctite High Tack to retain the gasket in position. I can now replace the cam cover. Again, it may seem like a quick and easy procedure. It is, if you're only inspecting the shoes and chains. It is a very detailed, very complex procedure, if you're going to replace those wear items. Either consult your manual or consult some professional help before attempting to do anything in this area. I can re-install one top bolt. Just bring it down snug so it holds the cover and the gasket in place. Always look directly through the holes on all of the bolt allocations. Make sure the gasket does not shift and you pinch the gasket when you re-install the hardware. With the cover and the gasket in place, I'll re-install all my prepped hardware, threading it in snugly by hand. Steel hardware into an aluminum crank case, it's no place for cross threads. With all the hardware re-installed into the outer cover, I'm confident the gasket didn't move, and I didn't pinch the gasket. I'll use my service manual, which has a very explicit torque procedure for the cam cover. It's kind of difficult to remember the proper procedure. So you definitely want to make sure that you use your book. I'll torque all these bolts to 125 to 155 inch pounds, according to the service manual. It is similar to a cross or a star pattern. But due to the fact there's so many and it's not on a circle like the derby cover, they do jump around a little bit in an awkward pattern. Use your service manual, save yourself a lot of headaches. With the cover re-installed, retorqued, I can remove my drain pan, set it out of the way. I can remove my mid brake mount bolts. Put a touch of blue Loctite on them. Again, I like to use the Klean N' Prime only if the bolts have been thoroughly contaminated with road debris or oil. You can use it all the time. It's a matter of preference. Work the way it makes you most comfortable I'll tighten the bolts down 'til they contact the brake mount. I know they're just about bottomed in the frame. I'll then torque them to the correct foot-pound setting found in your year-specific, model-specific service manual. I want to make sure before I re-install my front exhaust pipe that the gasket up in the cylinder head is usable. Again, it's like drain plug O-rings. For the cost of the gasket, discard it, put a new one in. Mark will bring me in the exhaust pipe. I'll make sure the flange is in position. Again, it's nice to have an extra set of hands. Put the pipe up into the cylinder head. I'll lineup both cylinder head studs with the flange. I've got just a touch of blue Loctite on the cylinder head studs, not on the nuts. I can thread the nut up into the stud. Just draw it tight by hand. It'll hold the pipe and give you a hand holding it in place. This is a critical area to make sure you start the threads to make sure they're not only clean but you can start them by hand. You don't want to break a cylinder head stud off, an exhaust stud off or cross thread the flange nut. Depending on the type of exhaust that's on your motorcycle, a lot of the aftermarket exhaust use a dog bone-style inner retainer and a bolt that goes into it from the bottom. This particular exhaust is that way. I'll slide it in, make sure the holes line up. Again, it's nice and easy when someone else is holding the weight of the pipe. I'll get my thread started by hand. Mark's holding the weight off the pipe so I don't have to worry about it sliding down out of alignment. When it comes to reinstalling exhaust pipes, always re-install all your fasteners before you fully tighten any of them. I've got two exhausted nuts on. I've got my two rear-most bolts retaining it to the bracket. And now I'm gonna put my center retaining bolt in under the cam cover, between the cam cover bracket and the exhaust pipe clamp. With all the hardware installed, I like to just move the pipe around a little bit. Check aesthetically for alignment up and down, in and out. Make sure it looks good, it flows with the motorcycle. And then I can tighten the two exhaust studs, the flange nuts to the exhaust flange. I'll snug them down. Then I'll torque them to factory specifications, which is 80 inch pounds. I'll do the same with the center bolt. Again, this is an aftermarket exhaust. You can refer to your service manual because this bracket does get used with a stock exhaust and torqued to a specific torque spec. But use common sense. If it seems too tight or too loose, tighten it or don't over-tighten it accordingly. With the center bolt tightened and torqued, the two exhaust nuts off the cylinder head torqued, I can now finish tightening the two retaining bolts that go through the mounting bracket into the dog bone-style retainer. With those two bolts tightened, I have now installed the exhaust pipe. I've installed the brake pedal assembly. I like to give it a couple pumps to make sure it's actuating correctly and I've got good brake lever feel. Not that I disturbed the brake system, but I did remove the brake pedal from the motorcycle. Make sure it's working correctly. With all these components re-installed on the motorcycle that should conclude twin cam cam compartment, chain tensioner, and shoe inspection.