billh
New Member
The following is presented here for reference purposes in the hope that it will help someone else avoid a potentially damaging problem.
About a month ago, I noticed what sounded like loose valve clearance, but only when the engine was all the way warmed up. Since the valve adjustment was done approx. 15,000 miles ago (at 110,000) and we had replaced all the shims, I was quite distressed. I had a coolant hose failure and had it towed to my local SHO tech. I had him fix the hose and troubleshoot the noise. He said it was coming from the valves on the passenger side of the engine, both front and rear bank.
The guy who did the valve adjustment lives in Portland, but was coming up this last weekend. Since I don’t have the tools or shims, he offered to re-check it. We pulled the intake, and the front cam cover. When he went to roll the engine over, hello! The bolt on the vibration damper was loose! The valves on the front checked out fine so we put it back together. I used a strap wrench, some blue loctite and put 120 ft. lbs. on the bolt. Still had a slight noise that sounded like a loose valve! Kicking myself in the ass for not checking the rear bank! Maybe chasing two problems! (Wouldn’t be the first time.)
This has now become an obsession. Late that night, I did a search for balancer problems, saw the photos of “Crank Cancer” I figure I have been driving the car for at least two months with a loose balancer. I need to find out what’s going on. Next morning, I pulled the balancer. It was very difficult to remove, but I managed it. Measured everything, and can find very little in the way of wear. The timing sprocket on the crank looks fine, the key was tight, the slot in the damper was polished on one side, but didn’t have any appreciable wear. I cleaned everything up, the balancer fit nice and tight on the key. I used some more loctite on the bolt and used a little **** on the washer face so I could get a good torque reading. After reading Scott’s posts, I now hit it with the full meal deal, 126 ft. lbs torque. I still fully expected to hear that same noise, but the engine is perfectly quiet. All valve noises are gone.
Simply putting the torque wrench on it and giving it 120 ft. lbs. apparently wasn’t enough. The only thing I can figure is that the friction between the bolt face and the crank was enough to give a false torque reading. OR, it really needed those extra 6 lbs.
About a month ago, I noticed what sounded like loose valve clearance, but only when the engine was all the way warmed up. Since the valve adjustment was done approx. 15,000 miles ago (at 110,000) and we had replaced all the shims, I was quite distressed. I had a coolant hose failure and had it towed to my local SHO tech. I had him fix the hose and troubleshoot the noise. He said it was coming from the valves on the passenger side of the engine, both front and rear bank.
The guy who did the valve adjustment lives in Portland, but was coming up this last weekend. Since I don’t have the tools or shims, he offered to re-check it. We pulled the intake, and the front cam cover. When he went to roll the engine over, hello! The bolt on the vibration damper was loose! The valves on the front checked out fine so we put it back together. I used a strap wrench, some blue loctite and put 120 ft. lbs. on the bolt. Still had a slight noise that sounded like a loose valve! Kicking myself in the ass for not checking the rear bank! Maybe chasing two problems! (Wouldn’t be the first time.)
This has now become an obsession. Late that night, I did a search for balancer problems, saw the photos of “Crank Cancer” I figure I have been driving the car for at least two months with a loose balancer. I need to find out what’s going on. Next morning, I pulled the balancer. It was very difficult to remove, but I managed it. Measured everything, and can find very little in the way of wear. The timing sprocket on the crank looks fine, the key was tight, the slot in the damper was polished on one side, but didn’t have any appreciable wear. I cleaned everything up, the balancer fit nice and tight on the key. I used some more loctite on the bolt and used a little **** on the washer face so I could get a good torque reading. After reading Scott’s posts, I now hit it with the full meal deal, 126 ft. lbs torque. I still fully expected to hear that same noise, but the engine is perfectly quiet. All valve noises are gone.
Simply putting the torque wrench on it and giving it 120 ft. lbs. apparently wasn’t enough. The only thing I can figure is that the friction between the bolt face and the crank was enough to give a false torque reading. OR, it really needed those extra 6 lbs.
