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Old 09-19-2013, 09:31 AM
Davect06607 Davect06607 is offline
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rebuilt Chevy 350 break-in issues

Hello all, let me start out by saying Thank You. I have been readings articles/wiki here for a few years and have learned alot of great information.

I decided to rebuild a chevy 350 for my '85 k10. Started with a 2 bolt main. Disassembled the block and took it to a trusted enigne shop. Block was cleaned, bored .040 over, crank polished, rods recondition, and cam bearings installed.

Block recieved all new bearings, oil pump, Summitt Pistons w/moly rings, freeze plugs, double timing chain. Pistons were just oem replacements and fel pro head gasket.

For cam, went with a Comp Cams Xe 262h, Hydraulic Flat Tappet. New hydraulic lifters, pushrods. Plenty of comp cams cam break in lube was used, 2 packets.

I reconditioned a set of 993 smog heads with; 2/3 angle valve job,new valves, ptfe seal w/guides cut, comp cams 1.254'' spring/locks/retainers, intake & exhaust ports matched, 1.52 roller rockers w/polylocks (was used). Studs was not replaced, threads were good.

Stock 70's GM dual plane aluminum intake manifold.

Problems begun when attempting to break in cam. I had a edelbrock carb with stock setting on the shelf for years, been using a pig rich holley. went with the edelbrock for first start. No good, all valve timing was off, and barely had any compression. Readjusted timing again and again and again. This whole time turning the engine over by hand, wiping all my lube off my cam.

Cranked aqnd cranked (eventually killing 2 batterys) the engine trying to get it to fire. Confirmed fuel and spark. Couldnt get it to catch at all, even with starting fluid. Threw the edelbrock across the garage floor and tossed in the gas loving Holley and a new ebay distributor.

Voila she rumbles to life, but sounds like ****. Adjust timing to 32' at 2250 rpms, ran it like this for 10 minutes. My assistant was blipping throttle and she died, went to restart and starter isnt engaging.

A week later, readjust starter/flexplate spacing. Start it up, and hear a loose rockers. Pull valve covers and readjust them all once again. Total run time maybe 5 minutes at 2200rpm.

I am about to mess with her again tomorrow, gonna try to get at least 10 more minutes of break in completed. Then change oil (Rotella-T w/comp cams additive was used for break in) and try to get her to idle. Once she is idling, pull valve covers and readjust rockers, and confirm any wiped lobes.

Basically what are my chances that the cam is wiped out? Im giving myself 50/50.

Sorry for the book, but wanted to include everything, and thanks again ALL.
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