How much free play should new timing chain have?

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1973dust

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So I slid the new double roller timing set on the 318 and it has 1/2" of slop. Sealed Power KT3-160S that claims to be made in USA although the bag the cam sprocket was in said Taiwan. The chain does say USA. I was expecting a new chain to to be tighter than that.
 
Should be tight. I don''t ever think I have had a new one that loose.
 
So I slid the new double roller timing set on the 318 and it has 1/2" of slop. Sealed Power KT3-160S that claims to be made in USA although the bag the cam sprocket was in said Taiwan. The chain does say USA. I was expecting a new chain to to be tighter than that.
Something is not right. The problem may be the chain itself, a manufacture's flaw? Extra link? Count the links on the old chain vs new one. Curious.
Norm
 
I got a comp chain setup with my cam kit and it was loose.Put a Mopar Performace one on and all good and tight.Never looked into it tho
 
IIRC newer 318s have a tensioner on the timming chain. Perhaps you need to spec an older model engine?
 
Should be tight. I don''t ever think I have had a new one that loose.
Something is not right. The problem may be the chain itself, a manufacture's flaw? Extra link? Count the links on the old chain vs new one. Curious.
Norm
Never thought to count the links but I went out and checked. Both are 34. However, I did notice that the bore in the crank sprocket has a couple thousandths more clearance than it should. It doesn't fit the crank as snugly as the original and you can actually rock it slightly. I'm guessing that one or both sprockets are just not machined correctly. Started thinking maybe I had a weird factory line-bored block or something as the original chain had a good 7/8" slop but the nylon teeth were all still intact. Never say never in Mopar land, right? However I checked the cam to crank center-line as accurately as I could with dial calipers and I came up right on 6.12" which appears to be correct. Looks like I'll be buying another new timing set. Should I go with the Cloyes street-roller? Kinda pricey, but I think I payed at least $50 for the set I have which is now a paperweight.
 
If it's just a stock 318 and you aren't driving it hard, a stock single chain and metal gears would be fine. You could add a tensioner if need be.
 
Did Chrysler use nylon covered timing gears like ford did in the 60s?

If that is the case remove them. SB Ford's of the time had them and I lost one at 160,000 miles just like the rebuild book said. I would never use one again.

I have used cloyes dual roller in the past no issues.
 
Did Chrysler use nylon covered timing gears like ford did in the 60s?

If that is the case remove them. SB Ford's of the time had them and I lost one at 160,000 miles just like the rebuild book said. I would never use one again.

I have used cloyes dual roller in the past no issues.

Yes, the stock cam gear had nylon covered teeth. That's why I'm replacing the factory set before the nylon teeth start separating. I'm just worried now that I'll buy another new set and it may not be any better than what I already bought.
 
How much did you spend? If you didn't spend "around" or over 100 bucks, you bought junk. Yes, IMO even on a stone stock engine you need a good quality chain set. IMO it's that important. What you get with a more expensive chain are bigger rollers, solid rollers and not the old split rollers. The 100 dollar plus sets are billet steel. I would not build even a stock engine now with less. Camshaft timing is as crucial to a good running stock engine as it is to a high performance build. This is why performance drops off some in a new build using lesser quality chain sets. Not saying you do this just making a statement.....if you always let price dictate your parts purchases, you will always come out with something inferior to what it could have been. And remember, the "about 100 buck" chain sets are not the most expensive. They are middle of the road. There are more expensive sets all the way up to belt drives, but in general the 100 dollar mark or "there about" is a good indicator you got a good set.

Now, as to the excessive play.....and it is excessive. The book spec is 1/2" play maximum before needing to be replaced. That's for a stock engine, not one that you want to have performance out of for any reasonable length of time and certainly not for a brand new one. While using a tensioner is ok, all that does is remove the slop. It does nothing to correct camshaft timing from a loose chain.
 
How much did you spend? If you didn't spend "around" or over 100 bucks, you bought junk. Yes, IMO even on a stone stock engine you need a good quality chain set. IMO it's that important. What you get with a more expensive chain are bigger rollers, solid rollers and not the old split rollers. The 100 dollar plus sets are billet steel. I would not build even a stock engine now with less. Camshaft timing is as crucial to a good running stock engine as it is to a high performance build. This is why performance drops off some in a new build using lesser quality chain sets. Not saying you do this just making a statement.....if you always let price dictate your parts purchases, you will always come out with something inferior to what it could have been. And remember, the "about 100 buck" chain sets are not the most expensive. They are middle of the road. There are more expensive sets all the way up to belt drives, but in general the 100 dollar mark or "there about" is a good indicator you got a good set.

Now, as to the excessive play.....and it is excessive. The book spec is 1/2" play maximum before needing to be replaced. That's for a stock engine, not one that you want to have performance out of for any reasonable length of time and certainly not for a brand new one. While using a tensioner is ok, all that does is remove the slop. It does nothing to correct camshaft timing from a loose chain.

I spent $50 which at the time I incorrectly thought would be decent quality. Obviously I was wrong. I think I have seen you recommend the Cloyes street billet true roller before which Summit has right now for $93.00. I also think I remember a post where you referred to advancing the stock 318 cam for a little more low-end without really hurting the higher end. Not like there is much up top to lose anyway. I've tried finding the post I remember multiple times and cannot locate it.
 
I spent $50 which at the time I incorrectly thought would be decent quality. Obviously I was wrong. I think I have seen you recommend the Cloyes street billet true roller before which Summit has right now for $93.00. I also think I remember a post where you referred to advancing the stock 318 cam for a little more low-end without really hurting the higher end. Not like there is much up top to lose anyway. I've tried finding the post I remember multiple times and cannot locate it.

Yup, that sounds like somethin I'd say. lol I wound't advance anything without a degree wheel, regardless.......and if I went to all "that" trouble, I'd unbutton "the other half" and recam the thing. Course, then you open the valve spring can of worms and "all that" so, if you're not ready to do all that, I would simply replace the timing set. If it was mine and I was lookin for more power, I'd go ahead and bite the bullet and just do a top end job on it. It likely could use a valve job anyway and while the heads are off, you can upgrade the camshaft and install the matching valve springs. Just a thought.
 
I have read about this a couple of times where a new double roller timing set is loose. I know you cannot use a tensioner with a double roller. What about single roller with tensioner? What about quality single non roller with tensioner? Sorry if this is hijack but may also help OP (and myself).
 
The factory chain had 7/8"! And the nylon teeth were all still there. Engine actually still ran fairly well.

That would be constantly changing cam timing. On a low h.p, street car might not be a problem.
 
That would be constantly changing cam timing. On a low h.p, street car might not be a problem.
It was on my teen. had to osolate the throttle to get her moving, but seam to rev just fine.
one day it popped and banged a couple of time.... and ran no more plastic timing teeth in the oil pan.

If it has been line bored the change can be loose

I only run Cloyes Tru Double Roller, Timing Chain, no matter the build. I may skrimp but not on a timing chain.

By the way, the teen ran flawlessly after the timing chain was replaced.
 
It was on my teen. had to osolate the throttle to get her moving, but seam to rev just fine.
one day it popped and banged a couple of time.... and ran no more plastic timing teeth in the oil pan.

If it has been line bored the change can be loose

I only run Cloyes Tru Double Roller, Timing Chain, no matter the build. I may skrimp but not on a timing chain.

By the way, the teen ran flawlessly after the timing chain was replaced.

I`m running the 9 keyway rollmaster , .005 under for line honed engines, was so dam tite almost couldn`t get it on , changed cams later on , still tite !
 
I`m running the 9 keyway rollmaster , .005 under for line honed engines, was so dam tite almost couldn't get it on , changed cams later on , still tite !
I made that mistake ones (wasn't line bored) could not get it on the Crank!!!!!
It's amazing how only .005" can really tighten things up.
 
if it had an extra link it would have a lot more slop than you say . just order one 5 thou shorter and be done .
 
Could be another reason for the slop if it's been line bored in the past by someone who doesn't know how to do it correctly. The correct procedure is to chuck the block up in the bore in such a way that the bar takes a very, very light skim off the main bore halves in the block and more off the main caps. Doing it in this fashion results in almost not moving the crankshaft center line in the least. Many shops will not take the time to set it up this way, so you end up with the crank center line that is raised, which results in the timing chain being loose. Of course you can get custom length chains for that, but who wants a bastard block like that when it can be avoided with good machine work?
 
Could be another reason for the slop if it's been line bored in the past by someone who doesn't know how to do it correctly. The correct procedure is to chuck the block up in the bore in such a way that the bar takes a very, very light skim off the main bore halves in the block and more off the main caps. Doing it in this fashion results in almost not moving the crankshaft center line in the least. Many shops will not take the time to set it up this way, so you end up with the crank center line that is raised, which results in the timing chain being loose. Of course you can get custom length chains for that, but who wants a bastard block like that when it can be avoided with good machine work?

The machinist must have taken some precautions w/ my block, a line hone, and a .003 cut on the decks, to square them , =zero deck heigth on my icon pistons , happy.
 
I don’t like the tensioners. I have personally had one come apart and the flat spring try to eat its way through the cover. Because the cam and crank center lines are so far apart on an LA we can also run a bunch os stroke, the down side is a long timing chain slapping around. I buy the absolute best chain I can find, IWIS I believe is the chain manufacturer
 
I don’t like the tensioners. I have personally had one come apart and the flat spring try to eat its way through the cover. Because the cam and crank center lines are so far apart on an LA we can also run a bunch os stroke, the down side is a long timing chain slapping around. I buy the absolute best chain I can find, IWIS I believe is the chain manufacturer
I put a tensioner in my 273 when I built it. I also used a double roller. If I was to do it over I wouldn't use a tensioner. It's really not necessary with a good double roller and in the grand scheme of things. Stock timing chains last 50,000 miles or more and I will never put that many miles on that engine. A stock rebuild on a daily driver with a single chain is a different story.
 
This one was in my 3.9 in my Dakota. It was real noisy! 120,000 miles if I remember correctly

 
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