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Original Message
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| 352 rebuild gone bad, second cam bad too? |
| By Eric - 07/29/2003 12:22:20 AM; IP 208.25.60.182 |
Here's the background: '66 352 from a F100. Fresh rebuild .030 over, Melling stage 1 RV cam with melling springs. I didn't precharge the oil system and cranked the engine instead. My static timing was right on so when the oil pressure light went out, I fired her up. Went right to 2200-2500 RPM for 5 mins and shut key off to check for leaks. On coast down, heard a "bad pop". Engine started back up and I finished the break in. The engine idled fine but when put into gear, didn't move. Short of the story was the front tranny pump siezed taking the converter drive tabs with it. Pull tranny, fix pump, new converter and back in business.
Truck drove fine so I procedded with ring break in. Light to moderate throttle then coast down. Engine started to devol slight miss. I had to bring idle up to 1100, in Park, to get 500 in drive. Oil pressure near zero. I pulled the pan and found small metal like the metal flake paints I use. Dropped the pan, cleaned it, new HV pump and back together again. High pressure now 10 psi at idle. Drove truck 20 miles and broke down. Pulled valve cover and found #3 exhaust valve not going up and down. I thought it had a collapsed lifter.
I fish the lifter out and find it all chewed up, cam is bad. Tow truck home, pull front parts off and try to pull cam. Cam won't budge and turns very hard. Inspection of front bearing shows clearance going lose toght when cam rotated. Pull engine and do complete tear down. #3 cam bearing toast, #1 and #4 in bad shape. #7 and #3 piston bores showing vertical scratches. Cam bearings and main look good. Clean block, new cam bearings, new Edelbrock Performer cam and lifters. Lubes lifter bottoms and cam lobes per instruction. Cam turns nice and loose.
Engine back in truck, static timed, primed with drill motor & gas poured in carb. Engine fires right up, runs good and I take it 3000 to 3500 RPM for 5 mins. Key off, check fluids, restart and back to 3000-3500 RPM for 20 mins. Drain oil and pull filter. Filter has more siver metal flakes in it. Flakes too small to feel but can see them in direct sunlight, OH-OH. Oil pressure started at 80 and went to 45 psi hot, by the way. Today, i pulled valve covers and watched the push rods. A few were turning good, a few slowly and a few hardly or not at all.
All this leading up to these questions:
1. Is metal flake bad in the oil after cam break in?
2. Some push rods not rotating, is this a sign of impending lobe failure or good the lifter be turning and the push rod not? |
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