I replace my timing chain and tensioner this spring before I went to flight school, I have since driven from Wisconsin to Colorado to Arizona to Mexico back to Arizona and then to Florida where I live now. All in all about 6 or 7000 miles since I replaced the chain. Just recently it acquired this odd metalic sounding rattle, so I just pulled the valve cover off and the driver side length of the timing chain is really loose. I can see where it has rubbed against the inside of the case too. What happened? It is still tight on the side with the tensioner, so I'm not sure what is going on. Here is a picture from when I did the chain in the spring for a reference

 

hmmm. what brand of timing chain is it?

maybe the chain went bad again? its hard to believe it would go bad with only 7k on it, no matter the brand.

can you get some pics??

 

Upon further investigation, the driver's side chain guide has been demolished, so it looks like I'll be taking it all apart again, but I still don't understand why it broke the guide?

 

dang sorry to here that.. sounds like a cheap timing set..

what kind of oil you running?

what brand is the chain?

 

It was a quality kit from http://www.engnbldr.com/

 

I got all giddy to reply then decided to read the replies... You nailed it man I was gonna tell you to check the guide and see if it broke.

I JUST fixed this same problem on my brothers 85. Engnbldr kit with the steel guide (only maybe 5-6k miles aswell), it broke at the top right where the head meets the front cover. The guide looked fine if you glanced down from the top but if you looked closer we found it was completely broken off. it kinda fell behind the guide and against the head wall.. RATTLING, sounded just like a loose chain.

Did yours break or wear through?

It's a pain fix, as you know, pulling it all apart to replace a guide (which is all you really need to do). We through a stock plastic guide in place of the metal one.

 

dang the rock knock.. no offense to engnbldr but i would try a different brand next time.. i like o.s.k.

 

I had plastic chain guides, do they really take that much stress, shouldn't all the slack be taken out by the tensioner on the other side?

 

yes the guides take a beating, but Ive never seen or heard them fail prematurely like that. and yes the tensioner takes up the slack.

what brand/viscosity oil were you running?

 

Mobil 5000 10w40

 

engnbldr doesnt sell plastic chain guides.........

the metal guide is plastic lined however....

 

So you pulled the timing cover without pulling the head...intresting....makes me wanna get in there and see why mine is sucking coolant..
I think I have a bad guide, and its wearing away at the cover...
But sorry for the thread jack...

 

Mine were all plastic, looking around engbldr's site, there is an option for metal driver side guide on the 85 and newer, but I have an 84

 

I pulled the valve cover, not the timing cover, but anyway you can pull the timing cover without unbolditing the head, I just dropped the oil pan when I did mine, needed to clean out the broken timing guide pieces anyway. Looks like i'll be doing the same thing now.


BUT I still don't understand why it broke in the first place? It should have gone another 100,000 without touching it, why only 6000? If I replace them again will it just happen AGAIN in another 6k?

 

A lot of people do the timing chain without pulling the head. There's just a chance of messing up the head gasket, and of course by the time the timing chain needs replacing, it's a good idea to do the head gasket, too. It does seem to be done quite a bit, though. I was considering it when I did mine, but turned out there really wasn't anything on my engine that didn't need to be replaced.

 

i believe he does.. part # TKS900.. he has a steel rail option though

 

it should have gone at least 50k.. i would try a different brand this time around. good luck and take some pics when you fix!

 

ah yea i see that now, hmm...

well, I've seen both metal and plastic ones broken now in my own experience.

 

is it just my eyes, or is that a single row chain?

 

its a single.. i heard they used both styles in 84.