All the bearingings save for 7 and 8 looked like new. The clearance was .0023 to .0025 for all the mains and rods before I fired it for the first time. Didn't take pics before I put it back together to keep everything in the same place.
Knockin' On Heaven's Door, what to do for a rod knock?
- Thread starter MrSony
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if 7 and 8 were shot and the rest was looking new then I'd be concerned why 7 and 8 were not lubricated. All the bearings were subject to the same conditions during break in and they all got the same "abuse". Plus if you had little or no oil pressure during the break in the cam and lifters would have suffered before the crank plus the valve train would have been making alot of noise.
The valve train was making noise after some time. I broke it in for 40 minutes, at 2000, 2500, and back to 2000. No noise. Drove the car 5 miles, no noise. Drove it another 2, faint tapping from the top end, indicating lack of oil. Installed the plugs, tapping went away and had 50psi cold at idle, 23 when hot. 23 hot at 800rpm idle upto 2500rpm or so, then from 3-6,000 a steady 60psi. I used moly graphite lube paste on every bearing surface, the cam, and the lifters pushrods and rockers. I think that stuff saved my engine. On Buick 350s the 7 and 8 rods are the LAST things to get oil. And my engine is basically stock. Only thing I've done to it is a .030 overbore, new cam, and swapped from a two barrel to a 4. As weird as it sounds, it wasn't the no oil pressure break in and drive, it wasn't the being boiled alive twice, it wasn't the almost frozen solid, it was 6k rpm and prolonged runs at WOT at 5500+ that killed the motor. It was a me problem.
I'm also pretty sure at WOT it was breaking up and detonating pretty bad. Tomorrow I'll take the top end off and peek inside.
I may have mispoke, but ONLY 7 got wiped out. 8 is fine. The difference on the crank is night and day. Almost new, and dicked up bad. I've looked at the plugs, and all 8 looked exactly the same. Light greyish brown, not wet or fouled, didn't smell of anything.
Is there any dirt on #7 bearing and could be the oil passage on #7 was plugged. Did you make sure the oil passages in the crank were clean when you assembled the engine?
set off car alarms with that thing within a 1000ft radius... seriously though, get your exhaust as quiet as you can make it while you are dialing in your motor... those little pings and spark knocks are more diagnostic tools at your disposal and you have to be able to hear them. once you are satisfied with your tune-up, you can run your noise makers.double hearing protection(plugs AND muffs) and even a wooden stick transfer the smallest noise without the backround interference(s).
what is the first thing that happens when a knock sensor goes bad on a newer motor with quiet mufflers and a well insulated cabin? it might be 1000 different things as one guy might interject with, the yellow light will only tell you it's happening, a limp mode is engaged to make sure you get home safely....
what is the first thing that happens when a knock sensor goes bad on a newer motor with quiet mufflers and a well insulated cabin? it might be 1000 different things as one guy might interject with, the yellow light will only tell you it's happening, a limp mode is engaged to make sure you get home safely....
how accurate is the timing pointer/harmonic balancer "0" compared to what "you" will calculate next time?
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