(Timing Chain Broke) ProGear double roller

[TurboBuRick]

Did a small hit on the street the other day. The engine popped and shut down right now. Tried to restart. I could hear there was no compression. Starter turning real fast. I pulled the cam sensor and took a peak inside. Chain is broke.

Never have I seen a Cloyes billet timing set fail. I have yet to pull the front cover and see the entire picture. Prolly do it later this afternoon. I'll keep yall posted.

Rick

 

[bison]

That sucks. Sounds like it tagged all the ex valves too

 

[TurboTdr3.8]

 

[trixdout]

Dam that is gonna be some work. Hope you have minimal damage.

 

[TurboBuRick]

That sucks. Sounds like it tagged all the ex valves too

I know it would be like winning the lottery if no valves got smacked but I pulled the rockers and all the valve seem to be ok. Whats the odds?

Rick

 

[bison]

I know it would be like winning the lottery if no valves got smacked but I pulled the rockers and all the valve seem to be ok. Whats the odds?

Rick

There's no odds. You already stated that when you crank it with the starter there's no compression. you would still have some pumping in the cylinders even with the valves not opening and closing. Besides it's impossible for all the valves to be closed at one time. Remove the rocker arms and fill each cylinder with air to verify leakage

 

[jpwalt1987]

Seems like there has been a rash of broken timibg chains in recent times. Scary really because when it breaks it's usually a ton of damage.

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[TurboBuRick]

I know you're right. No way all the valves made it without getting kissed. Looks like the motor is coming out.

Rick

 

[bison]

I know you're right. No way all the valves made it without getting kissed. Looks like the motor is coming out.

Rick

It's possible one side didn't get hit

 

[QwikStop]

i thought that was the best chain out right now?

 

[Nick Micale]

Rick, I would like more details about the chain as I worked with Cloyes a few years ago on a new double roller chain they just started to use then.

They actually tested one of these new chains after some use in my race car and found no stretch.

With the timing cover removed, also check the pan for small pieces in the pan that would be the broken ends from a link or more.

After a few broken chains in my car and others, it would be short of a miracle if you did not touch a valve or 3?

 

[earlbrown]

I know it would be like winning the lottery if no valves got smacked but I pulled the rockers and all the valve seem to be ok. Whats the odds?

Rick

If you've got a stock cam and a stock shortblock the odds are good.....

either bigger lift or less quench puts you in the interference zone

 

[Mike Licht]

check retainer to guide clearance or for coil bind on the valve springs. Dave Bamford broke 2 chains because his engine guy had the exhaust springs in bind.

 

[TurboBuRick]

Mike, coil bind was checked way back when the motor went together. This chain has prolly 10,000 miles on it and countless wot blasts.

Nick, I will snap pics and document my findings when it comes apart. Funny, this chain is about 2 years old.

Rick

 

[Mike Licht]

weird definitely not a common failure

 

[Rafs-T-Type]

I know you're right. No way all the valves made it without getting kissed. Looks like the motor is coming out.

Rick

So about 2 hours work for you? Sorry to hear about this Rick. Hope you get her back together soon and out on the streets again.

 

[turbobitt]

Not sure at what point the cam will hit the rods so you better look at that to.
AG

 

[TurboBuRick]

Luckily it's not a stroker.

 

[huntsg]

I feel your pain. Not too long ago I found a piece of a link when I changed the oil. I got lucky and changed the chain before it let loose. The one with the broken link was an Edelbrock double roller. I replaced it with a Rollmaster. Good luck

 

[TurboBuRick]

Got a chance to pull the timing cover last night.

It also appears that I did not bend a valve. I put compressed air to each cylinder. Each one pushed the piston down and held pressure.

Rick