I have a very slow coolant leak from the timing cover gasket. Last replaced 65,000 miles ago, and also did the chain & gears at that time. Should I plan to replace the chain and gears again too? Any pointers for making the gasket last longer?
Also, with the keyed shafts, its impossible to screw up the timing by installing the new parts wrong, correct? (As long as the engine isn't turned over when its disassembled)?

 

I would pull the cover, and see what ya got. If the chain still looks good, leave it. I use a bit of RTV around the coolant passages, on both sides of the gasket. Many years later, still no leaks. (of course, I sold that truck.....)

 

It’s been seeping for probably 3 years. The smell is noticeable only when the engine is partially warm, and the leak evaporates quick enough that it never drips. Should I bother fixing it, if my only symptom is a bit of a coolant odor when walking by the idling engine?

 

If its seeping now, it will eventually start leaking. The coolant will also eat away at the aluminum cover.... Mine was pretty pitted when I pulled it. Fortunately, some RTV still sealed it up good.

If your engine has over 100K miles on it, might want to consider changing the timing chain and gears when you pull the cover.

 

Engine has 255,000 and the current chain & gears have about 65,000. I bought the truck brand new back in 1997

 

Then it basically comes down to the "annoyance factor". If it isn't annoying you enough to want to fix it, leave it be till it is.

 

ok, that’s what I wanted to hear. I was just a bit concerned about corrosion on the gasket face becoming an issue, but if it won’t be an issue, I may just let it continue to seep until it begins to drip.

 

Worst case, the timing covers for the V-8's are still available. Mine was pretty eroded when I pulled it, but, gasket and RTV still sealed it.

 

Did the timing chain, sprockets, and gasket today. My antifreeze leak is now fixed.
I noticed a bit of a groove in the harmonic balancer where it rides against the seal, but it wasn’t leaking oil and I figured with a new seal it should seal even better than before, which was 100%. Well, I was wrong. I now have a small oil leak from the front main seal. I really don’t want to take it apart again, as that is a very ugly job. Would I be wise to just buy a new harmonic balancer and expect it to seal against the new seal that I just put in today? So all I’d have to disassemble would be the fan and shroud. I had the new seal and the harmonic balancer well-oiled when I assembled it all.

 

You can just buy a harmonic balancer repair sleeve. As far as the seal still being good I couldn't say for sure.