Quote:
Originally Posted by DDSLT5
Interesting - I wonder just how many LT5s have suffered loss of the guides (I assume this is what happened to your motor in the photo above - the guide was lost, and then the chain wore through the metal beneath it). One of my ZR-1s has 75K miles on it, runs like brand new, but that is the highest mileage I have on a motor - the other two are stroker builds with less than 15K miles on the build - only 4K miles on the other.
How did you discover this worn item? Just lucky? Or was there noise coming from the front end of the engine?
Thanks Sam,
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Actually when you hear significant noise from the cam chains it's mostly to late. Many parts (chain, guides, guide holders, etc.) need to be replaced. As you know LT5 parts are not a bargain.
I blowed my engine on german autobahn while I was on the way to a international Corvette meeting in Prague/Czech Republic.
The reason for the blow was the use of another engine oil viscosity.
While disassembling the engine with about 100'000 miles on the clock I noticed the bad chain guides.
I work on several LT5's. Do all maintenance and tuning works for the ZR-1 gang from some countries here in Europe.
You don't need to replace all 7 (2 cam cover, 1 primary chain, 4 secondary chain) guides.
Only those where the chain tensioner press against have a high wear. The guides on the opposite side look even after high milage like new or have a little wear. The small primary chain guide should also be replaced.
For these works the engine need to be taken out of car body.
If you wait to long with replacing the guides the cam chains rub on the chain guide holders. The swarfs can contaminate the oil-circulation system and damage the main/rod bearings and scratch all other rotating assemblies.
When you have the engine out of car you can clean it, replace all leaking gaskets/seals and time the cams perfectly.
If you guys want to prevent expensive engine failure (especially those who like to challenge the beast), check your chain guides after about 90'000 miles of use.
Just my advice.
Sam
PS: Attached a pic of the primary chain guide (used & new)