New Timing Chain Is Loose

[BobbySunshine]

Hi Guys,
As a new member, I want to introduce myself and ask for advice. I'm an old man with 50 years experience working on cars and trucks. However, this one has me stumped. I recently bought a 1977 C20 with a 305 and TH400 tranny. It ran like crap so I did a valve job on it. While I was waiting on my heads to be remanufactured, I decided to replace my timing chain. It was loose so I bought new gears and a chain. The problem is that the new chain is just as loose as the old one. I checked the block casting number and it is a 1977 305 engine. What could cause this? Bad Camshaft bearings? Bad Crankshaft bearings? Both cam and crank bearings? It ran rough and I learned that the heads were worn out completely. But, I don't want to put it all back together with 5 to 6 degrees of movement before the distributor rotor begins to move.

[JohnnyPopper]

Welcome from SoCal San Diego.

Sounds like a lot of slop but some here may say otherwise.

You could pull the pan and Plastic gauge your mains, but in reality, they would have to be really loose to cause that number.

The geometry between those two centers of violence (read 'excitement') is usually consistent.

Usually the gears are pretty reliable, who made the chain? Having said that, Where are ALL the parts from? So many IMPOSTERS!!!

[VileZambonie]

Normal

[BobbySunshine]

The new gears and chain are from Autozone and the brand is Duralast.
Are you suggesting that the problem may be the chain or gears? That was my thoughts at first but my mind has been going wild with worse case scenarios. I'm not the luckiest person so I always expect bad things. If it happens to be easy, then I'm happy. Either way, any help would be wonderful.

[dusterdude]

I would buy cloyes or sealed power

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[Shifty]

I would buy cloyes or sealed power

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Second the Cloyes, but the Sealed Power is not what it used to be.

[BobbySunshine]

Going to order a Cloyes timing set and see if that removes the slack. If not, I'll try to run it as is.
I'll keep everyone updated.
Thanks to everyone that chimed in. Even old guys like me run into problems they've never seen before. It's good to have other people to learn from.

[Shifty]

One question:  How centered is the cam as compared to the casting?  There was a lot of core-shift in 305's over the years, even some 350's. 

[BobbySunshine]

I have no idea about the cam.
I had changed a dozen or more timing chains in my life and didn't expect this problem. To be honest, it never crossed my mind that there could be a problem until it was assembled.

[FlatBlack77]

Not trying to insult you at all here.

I would not buy any internal engine parts branded Duralast.

At minimum I would say buy from Comp Cams or someone reputable like that.

[BobbySunshine]

No offense taken. I've used Duralast for the past 15 years or so and I've never had any problems. They may not be the best but, unless I'm doiing a complete tear apart and rebuild, all I need is for the components to last a few years. A new rebuild, I would use only name brands I trust. For something to last until I can find an engine to rebuild, Duralast works fine.

[FlatBlack77]

I agree. I hope you get this sorted out