Hello everyone. I have learned alot by joining you here and have a question. I am changing out my original opti and water pump (114k!) and am wondering if I should just go alittle further and change the timing chain and gears. My car is a '94 Z28, auto, with a bunch of bolt on and programming changes. It is not raced and I have a hard time prying the keys away from the wife since it is a convertible and summer time. I have been a auto tech for the last 16 years but I work on euro only cars and don't know much about these domestic engines and their lifespan. Thanks for your time and insight, and I enjoy checking out everyones cars. Jeff

 

Probably not necessary. But if you have doubts and if the valve train been modified it may be worth checking them out. Remove the front cover and check the slack on the timing chain and condition of gears. If worn, change both chain, timing gear gears, water pump drive shaft & gear, and replace at front cover seals.
http://www.enginebuildermag.com/Arti...lt1_enige.aspx

 

Pete, thanks for the reply. I think I am going to at least pull the front cover to inspect. I plan on keeping this car and it may be prudent to just change these parts and forget about them. The euro rides I work on have basically lifetime timing chain components and this pushrod unit is not all that familiar to me. Putting the distributor behind a water pump, who does that?

 

The good thing, unlike many of the overhead cam engines where if the timing chain or belt breaks the valves wind up getting damaged; if the timing chain breaks in this engine, nothing bad happens to the engine, except for it not running till the chain is replaced.

 

i did the timing chain on mine while looking for a oil leak. had to do the oil pan gasket to. it was brittle and when i losened the pan to get the cover off it didnt like it. glad i did it but it was a major pita. i have no oil leaks now. at 100k i couldnt tell the difference between the old chain and the new one.

 

Can anyone remember a timing chain failing in a stock engine? The big differents between a chain and a belt is that in the none racing world the chain just jumps a tooth. After that the engine will not start or atlease get up enough RPMs to jump another tooth. I have heard of many LT1s making it to 200,000 miles but most of the time when they do die its because of something other then the timing chain.

 

only heard of a tensioner failing gorn. it was on my 4.6 mustang gt, and resulted in one of my chains falling off... course that mustang was the worst investment i've made. many problems.

 

Good morning and thanks for the replies. I sucked it up and pulled off the front cover this a.m and found alot of slop in the chain. I was able to sneak the cover off without removing the oil pan. You can use stud extracter sockets on the 2 locating pins to break them free and you can slowly work them out of the block and pull them out with the cover. They will have to be modified to reinstall because a small amount of material in the pins that prevents you from pulling them out through the cover. Putting it all back together may be hard because of how the oil pan gasket fits into the cover. Anyway, I'm going to change the chain, gears, related seals and maybe the water pump driver if it is available locally. Hopefully I can sneak this cover back in without oil pan gasket issues, the pan looks awful to remove. My oil pan gasket is in good shape and had silicone in the corners like it may have been changed. I will keep you all posted on my success or failure on the reassembly. Thanks again