Head job time!! Cam Chain Broke
10-26-2008, 11:50 PM
#16
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Update: I had a couple hours on Friday so I took off everything but the actual head itself. Looks like the intake valves are a-okay! I'm guessing the chain broke on either the compression or exhaust strokes. Also, since the timing belt was still connected to the exhaust cam, I'm guessing the exhaust valves will be okay as well. Looks like all I'll be needing is a new J-pipe, cam chain, tensioner, and exhaust cam (cam sprocket broke) and all of the necessary while I'm in there stuff and I'm good to go.
Pictures coming in a few minutes!
Pictures coming in a few minutes!
10-27-2008, 12:30 AM
#17
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Now for some pictures..
So nothing really too significant here, you can see where the tensioner broke off, taking it's mount a long for the ride, as well as the broken cam chain, and if you look hard enough the j-pipe. The plastic tensioner piece I had already ripped off and threw across the garage, but it was lodged in the teeth of the intake cam sprocket.
By the way, I haven't actually gotten the chance to properly introduce the car.
It's a 1987 944S, Craigslist find. I got it in it's current non-running condition, the owner had no idea what was wrong with it, only that his brother "parked it one day and when he came back it wouldn't start". The car has a new clutch, Koni's, short shift kit, and a few other goodies. I got to have a lot of fun (by myself) picking it up, loading it onto the Uhaul trailer, hauling it the 50 or so miles back home, parking the truck, car and trailer on the top off my hill, unloading it from the Uhaul trailer, then rolling the car backwards back down the hill in an attempt to get it up my driveway. In the end I had to push it into the garage with my truck..
So nothing really too significant here, you can see where the tensioner broke off, taking it's mount a long for the ride, as well as the broken cam chain, and if you look hard enough the j-pipe. The plastic tensioner piece I had already ripped off and threw across the garage, but it was lodged in the teeth of the intake cam sprocket.
By the way, I haven't actually gotten the chance to properly introduce the car.
It's a 1987 944S, Craigslist find. I got it in it's current non-running condition, the owner had no idea what was wrong with it, only that his brother "parked it one day and when he came back it wouldn't start". The car has a new clutch, Koni's, short shift kit, and a few other goodies. I got to have a lot of fun (by myself) picking it up, loading it onto the Uhaul trailer, hauling it the 50 or so miles back home, parking the truck, car and trailer on the top off my hill, unloading it from the Uhaul trailer, then rolling the car backwards back down the hill in an attempt to get it up my driveway. In the end I had to push it into the garage with my truck..
10-27-2008, 04:52 AM
#18
RL Community Team
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Nice car! I think late interiors in black, with that 4-spoke steering wheel, are friggin sweet.
If you choose to have the head welded back together, have the welder also add an extra boss of aluminum to the front side of spark plug hole #3, to create a 3rd mounting point for the tensioner (give him the tensioner so he can see what he needs to do). This is a good mod, and that's how the 968 tensioner is. If you buy a new head instead of welding it, I still recommend getting a 3rd support point welded in.
To swap to an 8v head you will also need an 8v flywheel. yikes!
If you choose to have the head welded back together, have the welder also add an extra boss of aluminum to the front side of spark plug hole #3, to create a 3rd mounting point for the tensioner (give him the tensioner so he can see what he needs to do). This is a good mod, and that's how the 968 tensioner is. If you buy a new head instead of welding it, I still recommend getting a 3rd support point welded in.
To swap to an 8v head you will also need an 8v flywheel. yikes!
10-29-2008, 03:23 PM
#19
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Yes the parked it one day and it would not restart sounds correct. The plastic tensioner must stay in place even if it is broken while running, the chain just keeps slipping over the plastic. Then when the chain comes from a dead stop it has enough grip on the plastic that it can pull it off the tensioner. All of these failures that I have heard of have been on startup.
