All double rollers are not created equal

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Personal experience. Ditch the tensioner, I ran one and it came apart and the flat spring started to eat its way through the cover. It broke the plastic pad in half. It was NOT worn through. The cam to crank center lines are pretty far apart on an LA motor. Good for putting big stroke cranks in them, bad because the have long timing chains. Not ideal, I put a Rollmaster set in, billet sprockets and a IWIS chain. One place you get the best possible part and consider it a maintenance item.
 
These Tensioners are only to be used with a cordial link chain as described by mopar. Otherwise the tensioners cause vibration and excessive wear. This is the info from a mopar article where I copied these pictures from.

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post that article, Id like to read it. There used to be a high performance silent chain available too. I've seen V6's at the bone yard with these roller style chains and tensioners...looked like OEM stuff. Also watch the chain go over the tensioner pads, there is no bounce as its supported on more than one surface.
 
Toss the tensioner and get a "True roller chain" Not a "roller chain" Big difference. If you can't spin the individual rollers the chain is garbage.
Many guys use the tensioner. The tensioner was designed to use with the V6 engines in the late 80's due to the cam tunnel and the crank bore being out of spec. It was a cheap fix for bad machine work. I won't use them . Why put pressure on a tight chain to give it more tension just to promote stretch. But to each his own.

You can see by your pictures both of you chains are to long. When you can see the slack you will have issues. Get a new chain. You only get what you pay for.


Roller Timing Chains

Roller timing chains have been available since the 1960s. The chains have a semi-floating tube that covers the chain links, allowing the chain to literally roll over the gear teeth. This helps reduce friction and chain stretch.

There are two types of roller timing chains available. The single roller chain is much like the chain on a bicycle—the links or side plates of the chain pass over and around a single set of teeth in each gear. A double roller chain is exactly what the name implies—gears with dual sets of teeth with a chain link for each set. Many late model OE engines, like GM’s LS-series V8s, have a single roller timing chain. A single roller is also ideal for most high performance street engines. When you get way up in the horsepower and rpm strata where big lift cams and very high valve spring pressures come into play, a double roller chain can better control harmonic vibration at the cost of a little additional weight. That means more stable cam timing in the engine where even a little deviation can cost horsepower.

A variant of the roller chain is the “true roller.” This chain has pins or rollers that actually spin as they ride over the gear teeth. This further reduces friction compared to standard roller chains with rollers or pins that are fixed in place. You can get a true roller chain in single or double roller versions.

Some roller timing chain sets are manufactured with larger than stock pins. These are typically found in standard roller chains. This design yields a stronger, more durable chain, but adds more friction than a true roller.

Roller timing sets with iron cam gears have wear issues on iron engine blocks. Most engine builders machine the backside of the cam gear or the block area surrounding the cam nose to accept a bushing or a Torrington bearing. This prevents galling between the cam gear and the block. Many roller chain sets have steel gears to eliminate the problem altogether.

Another issue with a roller chain setup is the “chordal action,” a whipping motion that happens when the chain turns on the gear teeth. That whipping motion can literally turn the chain into an “S” shape. Chordal action can weaken the chain and also negatively affect valve timing, ignition timing, and mechanical oil and fuel pumps. That’s why it’s important to check the timing chain on regularly. If it’s tired, replace it.

That’s the short course on timing chains. If you’re planning to build a new engine, rebuild an old one, or simply replace a worn-out timing set, you now have a better idea of what chain will provide the performance you require.

This true roller chain below was on this race motor for 8 years .Its still tight and I'll reuse it on a street motor.

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Got a source for those claims of mismachined blocks? That would be interesting to be sure, and I'm going to wager paper money the chain tensioner was more about controlling timing as the engine wore to maintain emissions.

The chain tensioner should be used with a silent chain, (link chain) only. This is an all new set-up install maybe three years ago, you make the choice.

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Nothing wrong there. Once it wears down to the rollers, it's going to stop wearing and that wear won't amount to enough plastic at any one time to hurt anything. HD uses tensioners like this on their primary chains, and they last for decades. At best, I'd consider machining grooves into it so the wear wouldn't happen like that from the start.
 
HD uses tensioners like this on their primary chains, and they last for decades.
This is true, but the newer HD use a ratchet type of self adjustment as you can see in this photo see the teeth, there is NO spring pressure when chain gets a little loose it rachets a notch up. My old Sportster is manually adjusted not an issue. Also if you notice how thick the adjustment pad is.... by the time the rollers wear into the pad, as you say, the pad will be already split, mike it out let me. I think the tensioner is better left on the v-6's where its meant to be.

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55 posts and I'm more confused now than I was before I read any of this.
 
This is true, but the newer HD use a ratchet type of self adjustment as you can see in this photo see the teeth, there is NO spring pressure when chain gets a little loose it rachets a notch up. My old Sportster is manually adjusted not an issue. Also if you notice how thick the adjustment pad is.... by the time the rollers wear into the pad, as you say, the pad will be already split, mike it out let me. I think the tensioner is better left on the v-6's where its meant to be.

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Look closely at the surface of the chain and the material of the tensioner. Far different then the softer teflon tensioner being discussed here. Also the links were designed to work on that tensioner. flat and smooth.
 
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Look closely at yhe surface of the chain and the material of the tensioner. Far different then the softer tensioner being discussed here. Also the links were designed to work on that tensioner. flat.
I am pretty sure I side with you here. I will not ever use a tensioner there is no need....
 
Got a source for those claims of mismachined blocks? That would be interesting to be sure, and I'm going to wager paper money the chain tensioner was more about controlling timing as the engine wore to maintain emissions.



Nothing wrong there. Once it wears down to the rollers, it's going to stop wearing and that wear won't amount to enough plastic at any one time to hurt anything. HD uses tensioners like this on their primary chains, and they last for decades. At best, I'd consider machining grooves into it so the wear wouldn't happen like that from the start.


1980s introduction, the LA 239 V6 (and later the 3.9-liter Magnum V6) engine experienced a rattling or lifter-type noise in the timing chain cover area. As a fix to this problem, Chrysler issued technical service bulletin (TSB) #9-07-97 for the 1990-1997 V6 engines. The TSB required the dealership technicians to verify if chain/lifter noise existed, and if present, they were instructed to install a timing chain tensioner.
Why a link chain? First, we felt a factory-type link chain would provide a greater surface area to ride against the guides of the tensioner. This increased surface area would reduce the wear on the Teflon® surfaces of the guides.

A roller-type chain would dig into the guide surface to the point of the increased surface area of the roller links. Second, a link-type chain reduces chordal action. The term chordal action describes the rise and fall of each link of the chain at the time it makes contact with a sprocket tooth on a timing gear. The rise or fall results in linear variations of the speed of the chain, and if the rise and fall are significant, the camshaft operation may be jerky with excessive noise and rapid chain and sprocket wear. Our chain would have minimal chordal action resulting in smoother camshaft rotation, reduced noise, and increased timing chain longevity.

Lastly, the link chain design has a smooth tooth-to-link action, which reduces the link impact and, again, increases timing chain life. A disadvantage of the link chain design is its reduced ability to work well with increased camshaft loads. A second disadvantage, the link-style chain cannot operate effectively with complex chain layouts. In both cases, we believed our link chain would be acceptable because we were using a stock camshaft and valve train, and the timing chain layout was straightforward.

So if your going to be running a stock camshaft you will be able to run a tensioner safely with a factory type chain and gears. This type of chain is not strong enough for greater spring pressure and lobe lift when using a larger cam and springs as stated above.

You didn't have to ask me to prove anything this info it is available all over the web. I only copied it and pasted it. But guys like you just like calling people out because your probably one of the idiots that wasted your money on one. Before you ask for proof maybe you should fact check yourself.
I am only sharing this info to inform the many members who listen to salesmen like you and waste their money. You all can do what you want but don't say you have not been told.
If you are building a stock engine with a factory type chain and gears the tensioner can be used, If you are building a performance engine with a larger cam and a true roller chain and sprockets the tensioner should not be used . Remember use a "double tru-roller" not a junk "double roller" Double rollers are to look at and say you have a roller chain . Installing it is a waste of time.

As far as mis machined blocks. Why would you think some of the new engines had a chain slap? And why not just install another chain? We see mopar blocks like this getting done. Mopar blocks have a raised cam tunnel and have a problem being out of spec on late 80's and up engines . That is why you can get expensive different length chains for them. My R3 block has this issue as did one of my X blocks.
 
My 408 on a 5.9L engine was built w the double roller chain and a mopar tensioner. I did a refresh after a lifter failure wiped the cam 10 years later. Cleaned up everything and reused the roller chain and tensioner. Almost no wear on the tensioner pad, just polished. Plus I like the bracket for cam retainer better than original.
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My 408 on a 5.9L engine was built w the double roller chain and a mopar tensioner. I did a refresh after a lifter failure wiped the cam 10 years later. Cleaned up everything and reused the roller chain and tensioner. Almost no wear on the tensioner pad, just polished. Plus I like the bracket for cam retainer better than original.View attachment 1715864990
A lot of slack in that chain you pictured . Must be a chinese chain or improper fitment . How did you adjust the cam timing? 10 years and no wear on a teflon wear pad? Lifter Failure wiped the cam? and your happy with it?

Chordal action from the chain links rolling over the sprocket could have had something to do with the lifter spin interference. A tight arc in the chain over sprockets cause this.

What I wrote above did not come from me. It was copied and pasted from Hughes Engines. This info is a warning from many mopar engine information outlets recently. My son owns an engine machine shop and was also made aware and he will not use a tensioner on any small block Mopars with a tru-roller. Great to use with a factory style link chain with light tension valve springs where cam timing is not critical.

(quoted from article)

("The rise or fall results in linear variations of the speed of the chain, and if the rise and fall are significant, the camshaft operation may be jerky with excessive noise and rapid chain and sprocket wear. The chain would have minimal chordal action resulting in smoother camshaft rotation with a gear not a sprocket") JERKY CAMSHAFT OPERATION CAN CAUSE LIFTER SPIN INTERFERENCE
 
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1980s introduction, the LA 239 V6 (and later the 3.9-liter Magnum V6) engine experienced a rattling or lifter-type noise in the timing chain cover area. As a fix to this problem, Chrysler issued technical service bulletin (TSB) #9-07-97 for the 1990-1997 V6 engines. The TSB required the dealership technicians to verify if chain/lifter noise existed, and if present, they were instructed to install a timing chain tensioner.
Why a link chain? First, we felt a factory-type link chain would provide a greater surface area to ride against the guides of the tensioner. This increased surface area would reduce the wear on the Teflon® surfaces of the guides.

A roller-type chain would dig into the guide surface to the point of the increased surface area of the roller links. Second, a link-type chain reduces chordal action. The term chordal action describes the rise and fall of each link of the chain at the time it makes contact with a sprocket tooth on a timing gear. The rise or fall results in linear variations of the speed of the chain, and if the rise and fall are significant, the camshaft operation may be jerky with excessive noise and rapid chain and sprocket wear. Our chain would have minimal chordal action resulting in smoother camshaft rotation, reduced noise, and increased timing chain longevity.

Lastly, the link chain design has a smooth tooth-to-link action, which reduces the link impact and, again, increases timing chain life. A disadvantage of the link chain design is its reduced ability to work well with increased camshaft loads. A second disadvantage, the link-style chain cannot operate effectively with complex chain layouts. In both cases, we believed our link chain would be acceptable because we were using a stock camshaft and valve train, and the timing chain layout was straightforward.

So if your going to be running a stock camshaft you will be able to run a tensioner safely with a factory type chain and gears. This type of chain is not strong enough for greater spring pressure and lobe lift when using a larger cam and springs as stated above.

You didn't have to ask me to prove anything this info it is available all over the web. I only copied it and pasted it. But guys like you just like calling people out because your probably one of the idiots that wasted your money on one. Before you ask for proof maybe you should fact check yourself.
I am only sharing this info to inform the many members who listen to salesmen like you and waste their money. You all can do what you want but don't say you have not been told.
If you are building a stock engine with a factory type chain and gears the tensioner can be used, If you are building a performance engine with a larger cam and a true roller chain and sprockets the tensioner should not be used . Remember use a "double tru-roller" not a junk "double roller" Double rollers are to look at and say you have a roller chain . Installing it is a waste of time.

As far as mis machined blocks. Why would you think some of the new engines had a chain slap? And why not just install another chain? We see mopar blocks like this getting done. Mopar blocks have a raised cam tunnel and have a problem being out of spec on late 80's and up engines . That is why you can get expensive different length chains for them. My R3 block has this issue as did one of my X blocks.

What am I selling?

A lot of slack in that chain you pictured . Must be a chinese chain or improper fitment . How did you adjust the cam timing? 10 years and no wear on a teflon wear pad? Lifter Failure wiped the cam? and your happy with it?

Chordal action from the chain links rolling over the sprocket could have had something to do with the lifter spin interference. A tight arc in the chain over sprockets cause this.

What I wrote above did not come from me. It was copied and pasted from Hughes Engines. This info is a warning from many mopar engine information outlets recently. My son owns an engine machine shop and was also made aware and he will not use a tensioner on any small block Mopars with a tru-roller. Great to use with a factory style link chain with light tension valve springs where cam timing is not critical.

(quoted from article)

("The rise or fall results in linear variations of the speed of the chain, and if the rise and fall are significant, the camshaft operation may be jerky with excessive noise and rapid chain and sprocket wear. The chain would have minimal chordal action resulting in smoother camshaft rotation with a gear not a sprocket") JERKY CAMSHAFT OPERATION CAN CAUSE LIFTER SPIN INTERFERENCE

Slap a timing light on the damper with a tensioner installed versus not, and get back to us about which camshaft is spinning smoothly and which isn't.

That pad isn't teflon, by the way.


My 408 on a 5.9L engine was built w the double roller chain and a mopar tensioner. I did a refresh after a lifter failure wiped the cam 10 years later. Cleaned up everything and reused the roller chain and tensioner. Almost no wear on the tensioner pad, just polished. Plus I like the bracket for cam retainer better than original.View attachment 1715864990

Careful, after ten years, that lifter failure is clearly related to the tensioner.
 
Get a good quality timing set, and be done with it.

Give the tensioner to the paper boy.
 
My 408 on a 5.9L engine was built w the double roller chain and a mopar tensioner. I did a refresh after a lifter failure wiped the cam 10 years later. Cleaned up everything and reused the roller chain and tensioner. Almost no wear on the tensioner pad, just polished. Plus I like the bracket for cam retainer better than original.View attachment 1715864990
Proper tensioner with correct style roller chain. You did it right.
 
"All double rollers are not created equal" This is true and if you want the best, indeed buy a "true roller chain". As the picture shows using a needle nose pliers I can twist the barrel and the link twist with the chain, this is extra wear on the pins and gear sets. Now with a true roller there is an extra barrel around the pins that rolls easily, less friction, less heat and less wear. So double rollers chains may not be what you expect, true roller is what you should use.


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Before I installed the tensioner that failed I was in your shoes. This is one of a couple of topics where you have smart experienced people on both sides and you just have to choose. I chose to put one in and won’t do it again. Could I use one and have no issues? Maybe, but with the proper length chain and a block that hasn’t been line bored to death not needed in my book.
 
I think through thorough discussion we've determined you can use a tensioner on a double roller if it's the "right" kind.
 
For oldmanmopar, I apologize I made a remark that I regret.
A lot of slack in that chain you pictured . Must be a chinese chain or improper fitment . How did you adjust the cam timing? 10 years and no wear on a teflon wear pad? Lifter Failure wiped the cam? and your happy with it?
No I am not happy that a roller on a lifter failed, but I bet you can't prove that the tensioner caused it either. I did not dispute anything you had said up to that post. I just posted my observation and experience.
 
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For oldmanmopar, kiss my ***. I just posted my observation and experience.

No I am not happy that a roller on a lifter failed, but I bet you can't prove that the tensioner caused it either. I did not dispute anything you had said up to that post.
I saw nothing disrespectful with his post, yet you give him this? He was simply pointing out an observation and asking a question.
 
I am sorry, I deleted the remark. I took his obsservation as criticism.
I wouldn't sweat it. I don't think that's how he meant it. Besides, if I had a dollar each of my snarky comments, I'd have a pretty big sack. I am trying to be better though, everyday.
 
Sometimes I say things I don't actually mean myself. I am only giving info to members on all things I have seen over many tears of experience with these cars. I myself learn things every day on this site . That is why I keep paying my $40 a year for gold. We're all a family here. I have 4 sisters and I call them assloles more then I should . If I wouldn't love them I would walk away and let them screw up and then just laugh.

You all would not believe how many of those cheap rollers chains I put on over the years . And then in a month I'd want to try another Cam shaft. When taking the cover off the chains were loose. Wasn't until some builders pointed me to tru rollers that I started spending the extra cash.

You know there are times you really don't have a clue what people really know . Had a drag truck here. The guy raced every weekend. We built him a stroker motor the truck was in the 10's.

He pulled in the one day and told my son and I that his bands were weak in his transmission. Why do you say that I asked? He said they don't have the snap they use to have on the shift. He asked us if they made any out of a stronger rubber? My son and I started laughing I had tears in my eyes. He was serious . He actually thought there were rubber bands in the trans that would wind up and snap loose for the shift.

So how can you tell who you are telling anything in this hobby. This guy was 40 years old and racing since he was 18 years old.
 
Running the MP tensioner and Summit brand billet 9-keyway, two different cams, 4 years use no issues, no concerns. I haven’t been (and won’t be) convinced there is or will be a problem running one. And I run that oem slinger-ma-bob too. No issues, no fouling or rubbing on anything. Haven’t been convinced it’s bad or will go either. Both work as they should on my engine.

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No one ...EVER... says NOT to run an oil slinger. That not even even a question here.
When under post the timing is solid, as said. Only deceleration and idle does the tension really do much.
*The valve springs are stiffer than that tensioner is...it still moves/jogs...just a lot less..and not as erratic.
 
This is true, but the newer HD use a ratchet type of self adjustment as you can see in this photo see the teeth, there is NO spring pressure when chain gets a little loose it rachets a notch up. My old Sportster is manually adjusted not an issue. Also if you notice how thick the adjustment pad is.... by the time the rollers wear into the pad, as you say, the pad will be already split, mike it out let me. I think the tensioner is better left on the v-6's where its meant to be.

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People confuse guides with tensioners all the time. The fact that there is varying load through is perhaps where some confuse it .
 
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