I was coasting down a hill loaded with Jake brake on and engine at about 1700 rpm’s. When I went to accelerate my truck started missing as soon as I hit the pedal and and could smell raw fuel. I pulled over raised the hood and checked everything, I noticed fuel traces coming from around the #6 exhaust manifold, I guess where the exhaust gasket was leaking. I towed it back to the shop where I pulled the valve covers. The back bridge over the intake valves had jumped off. So I put it on and adjusted the clearance being there didn’t seem to be any damage. When I started it, it was no longer smoking raw fuel, but had a deep thud sound. I started watching the exhaust valves on the #6 and noticed it was not pushing the valves down very far at all compared to the others. I rotated the engine back to the 1/6 mark on the flywheel and the intake valve was still adjusted right but the exhaust had alot of slack. At the time I couldn’t find anything on how to adjust the valves with the Jake so I just tightened the adjustment over the push rod and the nut is even with the top of the screw in stud on top of the pushrod which is about 6 threads more than any of the others. I visually checked everything else on that rocker arm and bridge and it looks about the same as all others. I turned the engine over manually to make sure my valves didn’t hit the pistons. The truck runs and sounds good now and I plan on going over all the other clearances on all the other cyls. Since I found the correct procedure. I just want to make sure I’m not going to have to tear into it first. I was wondering if anyone knows what could have caused this to happen. All of the adjustments where tight and this happened all at once, no missing or any other problems. I also pulled out the push rod and it looked good. Thanks in advance for any help.
Question
Jvmack
I was coasting down a hill loaded with Jake brake on and engine at about 1700 rpm’s. When I went to accelerate my truck started missing as soon as I hit the pedal and and could smell raw fuel. I pulled over raised the hood and checked everything, I noticed fuel traces coming from around the #6 exhaust manifold, I guess where the exhaust gasket was leaking. I towed it back to the shop where I pulled the valve covers. The back bridge over the intake valves had jumped off. So I put it on and adjusted the clearance being there didn’t seem to be any damage. When I started it, it was no longer smoking raw fuel, but had a deep thud sound. I started watching the exhaust valves on the #6 and noticed it was not pushing the valves down very far at all compared to the others. I rotated the engine back to the 1/6 mark on the flywheel and the intake valve was still adjusted right but the exhaust had alot of slack. At the time I couldn’t find anything on how to adjust the valves with the Jake so I just tightened the adjustment over the push rod and the nut is even with the top of the screw in stud on top of the pushrod which is about 6 threads more than any of the others. I visually checked everything else on that rocker arm and bridge and it looks about the same as all others. I turned the engine over manually to make sure my valves didn’t hit the pistons. The truck runs and sounds good now and I plan on going over all the other clearances on all the other cyls. Since I found the correct procedure. I just want to make sure I’m not going to have to tear into it first. I was wondering if anyone knows what could have caused this to happen. All of the adjustments where tight and this happened all at once, no missing or any other problems. I also pulled out the push rod and it looked good. Thanks in advance for any help.
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