2000 Chevy Astro 4.3L CSFI Vin W part 2

ASTRO

MEMBER
2000 CHEVROLET TRUCK

Replaced intake gasket. Engine performance improved. BUT. Went on a road trip (1100 miles round-trip. 30 miles from arriving home, started to misfire (constant). After compression test (#6 and #4 bad), decided to replace the head gaskets. And what fun it was. Had two bent valves, HEAVY carbon build up on valves. Cleaned and inspected heads for cracks. Installed two new valves, lapped all valves, replaced valve seals. Everythings back together, fired her up, tap. Tap. Tap (when you lightly touch the gas pedal there is also an intermittent knock. Sounds like something is hitting the bottom of the intake. What am I looking at hear, bent push rods? Did the bearings go on the balancer shaft? I feel pretty sure some valve adjusting will clear-up the tapping, but the Knock sounds bad.

Sunday, April 15th, 2007 AT 12:01 PM

1 Reply

ASTRO

MEMBER
12 POSTS

I removed the valve covers today to start checking for the obvious, and I found it. I have a bent push rod on the #2 exhaust, the rocker arm bolt is broken, and so is the end of the rocker arm support (rocker pedestal or rail) whatever the correct term is for the bar they rest on. I applied enough pressure to the valve to make sure it wasn't stuck, I was able to depress it with little effort, so I don't suspect a bent valve. I don't know a whole lot in this area, and need to know what my next step should be.
Could it be that I simply didn't have the push rod seated properly on the lifter. And I can get away with installing a new support/push rod/rocker arm & bolt. Or is it likely that there is more damage below the surface. Did something else cause these parts to break (a bad lifter? camshaft?) or vice-versa did the damage I found so far, most likely damage the lifter, cam, etc.

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Monday, April 23rd, 2007 AT 8:01 AM