1973 Z28 Restoration "Lilith"

70 73z28

New Member
Mar 17, 2006
8
Troy, Mo.
Well, your valve springs breaking part of the story made me realize other people had that problem also. I ordered my Z28 in the spring of 1973. Within a few weeks it broke a valve spring. I went to the dealer and bought a new spring and installed it. About a month later, it broke another one. I figured I was about to run out of luck and a dropped valve was coming. So I went to the dealer and ordered a full set. When I replaced them, I discovered that the springs had a color stripe painted down their sides. I had 3 silver ones, 4 brown ones and the rest were purple. (The two that had broke were silver.) The new ones were all purple.
I think the factory color codes them as to what cam/engine they should be used on and the person that put my heads together was just using whatever was handy!
 
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73rsltz

Veteran Member
Lifetime Gold Member
Aug 19, 2013
236
taylors,sc
Mmm that might explain why one of the heads had been off my car before I bought it. The drivers side had the tach wire pinched between the head and block. It still had all the factory pistons when my brother and I replaced the head gasket in 1991..
 

Jerry73Z28

Veteran Member
Gold Member
Nov 1, 2017
229
Greeley, CO
I know the Z28 engine has "special" valve springs. Dad checked with the machine shop while they were rebuilding the heads to make sure they were putting in the Z28 ones. There was an "oops" moment and they swapped them out for the right ones. Honest mistake.
I'll have to look and see if they have any color coding on them. I know they're right, just curious to see if it's still done.
 

70 73z28

New Member
Mar 17, 2006
8
Troy, Mo.
Mmm that might explain why one of the heads had been off my car before I bought it. The drivers side had the tach wire pinched between the head and block. It still had all the factory pistons when my brother and I replaced the head gasket in 1991..

I would not suspect that the dealer or factory would pull a head to replace a broken valve spring. When my first one broke, I took and old spark plug and broke the ceramic out of it. I then tapped it with a pipe tap to accept and air hose nipple. I could screw that into the plug hole and connect an air hose to it with 120 psi. That valve is not going to move while you take the springs off then. Just be careful to be clear of the fan, because if that piston is up, it will be going down which will turn the engine. Also, take both rocker arms off on the cylinder so you won't have an open valve.
 

73rsltz

Veteran Member
Lifetime Gold Member
Aug 19, 2013
236
taylors,sc
I would not suspect that the dealer or factory would pull a head to replace a broken valve spring. When my first one broke, I took and old spark plug and broke the ceramic out of it. I then tapped it with a pipe tap to accept and air hose nipple. I could screw that into the plug hole and connect an air hose to it with 120 psi. That valve is not going to move while you take the springs off then. Just be careful to be clear of the fan, because if that piston is up, it will be going down which will turn the engine. Also, take both rocker arms off on the cylinder so you won't have an open valve.
Motor was just completely rebuilt should be starting it up soon. That was in 1991. A long time ago
 

70 73z28

New Member
Mar 17, 2006
8
Troy, Mo.
Motor was just completely rebuilt should be starting it up soon. That was in 1991. A long time ago

That's great! Have fun with it. The first start is like watching a baby being born! I built a period correct LT1 for my 70 RS Z28 last spring and I am currently putting the L82 back together for my 73 Z28.
 

73rsltz

Veteran Member
Lifetime Gold Member
Aug 19, 2013
236
taylors,sc
Oh yeah. My car is almost done. My brother installed the exhaust from Joey yesterday. Should be starting it up soon.
 




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