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Discussion Starter · #1 ·
what is the name of the part that the push rod sits in at the bottom? it rides on the cam, I am working on cleaning out the main chamber, and one of those part has it retainer clip falling out, I need to figure out how to install it correctly
 

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It is also called a tappet, because back in the days of Chevy six cylinders they all came equipped with a solid flat lifter that made a constant tapping noise. The flat hydraulic lifter installed in your 283 was installed for the first time in 1955 as a means of quieting down engine noise and removing a source of engine maintenance (adjusting the flat tappets to compensate for wear).

The fact that the retaining clip is coming out of yours indicates to me you have suffered a symptom of one of the limitations of a hydraulic lifter. It pumped up and then collapsed again allowing the retaining clip to fall out as the piston bottomed out in the bore.

This occurs because hydraulic tappet lifters require weak springs that can not keep the lifter in contact with the cam lobe at high RPM. So as a result of taching your little 283 up it first made a tapping sound and the cylinder went dead which probably scared you enough to get off the throttle and explore the source of the tapping noise.

Good thing you did because had you not done so, the push rod would have jumped out of the cup and tried to go for a walk about in the engine (I have found them wrapped around a cam making removal a joy, or chopped up by the crank into metallic confetti. most of the time they just get bent as the valve hits the piston and lay in the lifter valley.

I suppose you are wondering how I could possibly know these things since I wasn't there to observe any of it. All I can say is welcome to the club as I have grenaded a fair number of 283 and 327 small blocks; spinning them far higher than their red line allowed in my youth. Back then a 283 could be had for hauling it out of someone's yard, but those days are long gone. The 283 was the reason SUN tachometers went to 10,000 RPM. With solid lifters and a Clay Smith cam or a Harvey Crane cam, and stiffer springs; it could easily hit that RPM mark before a rod bolt let go (we didn't have ARP rod bolts back then either). I used to peg the 10K tach frequently on a Friday or Saturday night, before I discovered 348 and 409 motors.

Big Dave
 

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Discussion Starter · #5 ·
WOW interesting info Big Dave, that's some history, I'm new around here and around the 283, but I've heard that this design is reliable within it's parameters of design, I plan to rebuild it and will insist on improved quality parts for it, it's is matching numbers to the car and this project is aim at originality so no drag racing haha...thank you for your insight and help, cruising it is a joy worth all the work... Nacho65SS
 
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