What's your opinion on the slack in this 318 timing chain?

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67CBodyGuy

67CBodyGuy

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I'm tearing into this because of a coolant leak between the timing cover and the block, otherwise I wouldn't be here. I was curious about the condition of the timing chain. This engine was bought from a Chrysler dealer, it came from an authorized rebuilder in Toronto (Ontario Reman) circa 1986 and I might have 10k miles on it at this point.

570.jpg


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Sprocket made in Canada? Links made in Japan?

From what I read, even new timing sets have slack, maybe more than some people want or expect. I didn't measure the slack here, I can, but it looks like 5/16 inch. I haven't driven the car much in the past 2 years (was in storage for 20 years before that) but I'd like to see a smoother idle, don't know if it's the crappy gas now, or my expectations of 550 rpm, or the carb setup, or still having points (not electronic) ignition - or this chain?

I'm going to have to decide in the next couple days if this chain is staying on or if I'm going to replace it. Comments?
 
If you gotta ask, CHANGE IT especially since you're obviously apart enough to expose it
 
I’d bring it back for warranty.
Seriously- if you are in that far, change it. Why doubt yourself and question things later. $100usd for an awesome chain and your done.
 
IMO, the fact that it's a double roller is all the more reason it shouldn't have a lot of slack. Generally, the go no go is 1/2" of play. If accurate camshaft timing is important to you, put a JP/Rollmaster set on it. If it's not, just use something else, or stick with what you have.
 
You state 10k miles and in excess of 20 years on rebuilt. I would run it the way it is. I would choose those older parts over the new chinesium parts that you're gonna replace with never mind the co$t. Just my opinion
 
Since you have the front off, I would replace the timing chain. Not that expensive......
 
I can buy a set for $50 or $200. And it might still have the same slack. Because maybe I need a shorter chain. From what I read, a new set can be a crap shoot. This is a rebuilt engine.

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There is a way to check it and a spec... look it up see if it is within spec. I'd look it up... but Ill say it anyway 1/2 inch is too much slop when checked properly so, if it is 5/16 its ok to run.
 
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The spec distance seems to be 6.125 inches. Cloyes has race billet sets for 6.120 and 6.115. I don't need a race billet with adjustable sprocket, but I would entertain an affordable set for 6.120 just to buy and try. But who makes them? Who sells them?

Are belt kits available for the 318?
 
There is probably nothing wrong with yours if the slack is less than a half inch...

copy and pasted from the web:

The proper way to do that would be with the timing chain cover off. Essentially you're supposed to put a straight edge across the gears and measure the slack in the chain by pushing on it to see how much deflection there is from the staright edge.

You can stick your finger in the fuel pump hole and push on the chain but you really can't measure the actual deflection. The best you can do is get a ballpark guess from what you feel.

You need to make sure all of the chain slack is on the fuel pump side before taking he measurement. You may have to put a socket on the big honkin' nut on the crank and turn the engine a bit (counterclockwise I think) by hand to do this.

The shop manual says that if there is more than 1/2 inch in deflection in the chain then it should be replaced. If the chain is really loose you might be able to feel it out through the oil pump hole.
 
I think that is a bunch, if they line bored the block. That brings the cam and cranks center lines closer together. I like IWIS chains. It would bug me, but it is a stock rebuild.
 
67CBodyGuy said:
I'm tearing into this because of a coolant leak between the timing cover and the block, otherwise I wouldn't be here. I was curious about the condition of the timing chain. This engine was bought from a Chrysler dealer, it came from an authorized rebuilder in Toronto (Ontario Reman) circa 1986 and I might have 10k miles on it at this point.

View attachment 1716291817

View attachment 1716291818

Sprocket made in Canada? Links made in Japan?

From what I read, even new timing sets have slack, maybe more than some people want or expect. I didn't measure the slack here, I can, but it looks like 5/16 inch. I haven't driven the car much in the past 2 years (was in storage for 20 years before that) but I'd like to see a smoother idle, don't know if it's the crappy gas now, or my expectations of 550 rpm, or the carb setup, or still having points (not electronic) ignition - or this chain?

I'm going to have to decide in the next couple days if this chain is staying on or if I'm going to replace it. Comments?
Click to expand...
Probably fine, but change it if you want.
 
67CBodyGuy said:
The spec distance seems to be 6.125 inches. Cloyes has race billet sets for 6.120 and 6.115. I don't need a race billet with adjustable sprocket, but I would entertain an affordable set for 6.120 just to buy and try. But who makes them? Who sells them?

Are belt kits available for the 318?
Click to expand...
Millions and millions of cars have been running around for billions of miles with that much or significantly more slop in the timing chain set for the last sixty years with no negative effect. I bet you can't see any variation in the timing at idle and under load it sure isn't going to cause a problem. You want to throw $500 belt drive on a re-manufactured stock 318? Come on, man!
:lol:
 
Like said there is a check procedure follow it and OP, you'll find you are ok with what you have there.
 
I've had new outta the box cloyes double roller sets that were that bad or worse, each time I've gone back, returned it and bought an Edelbrock true roller set and the fit is much better.
I've taken those engines apart and swapped cams with the Edelbrock chain set and reused the chain set because they had less slop than what you are showing. I'm done with cloyes unless it's new from 40+ years ago
 
before you install new set or chain, remember to submerge the chain in motor oil for a while before installing. A day or so be good, then all the links and rollers will have oil in them at first start.
 
When I checked the slack in Bazza's 318 last summer I ran across a little tidbit of information (here or elsewhere, I don't recall) that said that if there was 5* of "slop" between the timing marks when you rotate it backwards and forwards, it's worn-out. Not sure if that was "By the Book", but I followed it.

And I took a video of this for Bazza as well:



Another way of thinking about this: If there's slack in that chain, how accurate is your timing going to be, and thus, how well is your engine going to run?

Of course you could always just say, "Screw it! I'm already in here, and I may as well take care of it", which is what I would do.
 
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