Timing chain slop?

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KnuckleDuster

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How much slop is normal without a tensioner?
I have a 68 318 I'm getting ready to throw in my truck. Supposedly a fresh dingle ball rebuild...hey, it was cheap!
It has a newer Purple Shaft 268° in it which the seller gave me reciepts for along with a few others for labor and such. Story goes he was going to have it bored but the shop ( Austin Quality Engine) said it didn't need it as there was no ridge and still some cross hatch, so they honed it and called it a day. They put new cam bearings, Hastings 148 rings and the cam kit (P4452761) in it. I pulled the timing cover last night and the chain has a good half inch of slop on the thrust side and probably 3/4" on the right side. It's a single roller and at least not nylon coated, but I have to think there is way too much play.
While I have taught myself through rebuilding just about every other part on my car, I had a good friend assemble my 410, so I'm still new to engine building. I saw this as a good opportunity to learn to degree a cam and I have been told advancing it might be a good idea for low end torque in a big heavy truck.
...anyway, looking for a little advice.Wondering what is normal play on a new timing set?
I am probably going to replace it with a decent double roller, but I need to learn how to measure to get the correct size set. Being the pistons are .040, I bet the crank has been turned.
This is a dirt cheap swap, I'm not expecting the world out of this engine, but as long as I got it open I'd like to do what I can within a couple hundred bucks.
The truck is an 85 D150 short bed. The transmission went out, the engine in it has 130,000 miles and was a dog anyway. I picked up the 68 318 for $250 and a 15,000mi rebuilt 727 out of a 78 LRE with a fresh 2500 stall converter for $300.
Just looking to get the truck on the road again and have a little fun with it while I find and build a 360 or maybe even a 440 to go in it.
 
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Install the tensioner. Had the same amount of slop as you when I put a used engine in my Ram.I DID NOT install a tensioner an wished I did.
 
I would replace it with at least a Cloyes street true roller timing set 9-1103.
The crank sprockets have three keyways for timing adjustment--4 degrees retarded, 4 degrees advanced, and normal. and you can order offset cam or crank key ways to dial it in if you are degreeing it...Oreilly's can get it out of Dallas overnight...
Back to work
 
Chain sets and tensioners are cheap. How cheap are you?
 
I was already planning replacement.

Martin, I have cam keys....somewhere.
 
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A new timing set will have very little slack; sometimes you have to line the sprockets up on the cam and crank juuuust right to get them all to slip into place.

With all of the slop that your chain has, I would expect the cam will run retarded 3-5 degrees; that will make a VERY noticeable difference in off-idle torque and low to mid RPM throttle response, in a stock or mildly cammed engine. So you for sure want to replace that!

As far as advancing the cam timing, yes, some advance tends to help low end torque. 4 degrees + or - is a number to suggest. If this is an aftermarket cam, it may have some advance already ground into it. What cam do you have?
 
Found the pn, It's an Autozone special timing set.
Cloyes set recommended by TXDart is on the way along with the Cloyes tensioner...
Cam is a MP Purple Shaft 268.
 
Found the pn, It's an Autozone special timing set.
Cloyes set recommended by TXDart is on the way along with the Cloyes tensioner...
Cam is a MP Purple Shaft 268.
As said get a new one with the 3 keyways & adv it 4 deg or use the offset keys if you have them. I just did this on my 318 truck & it had slop like yours does. I ain't quite together yet but I am anticipating I will be pleased (& I am recurving the dist)
 
Yeah Robert, thanks, I hear you.
Being an 85, the distributor might have 22° in it.
 
While I have taught myself through rebuilding just about every other part on my car, I had a good friend assemble my 410, so I'm still new to engine building. I saw this as a good opportunity to learn to degree a cam
BTW, my hat is off to you for digging and learning this stuff. Sounds like you have a good future in gearhead land!
 
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