I have a 94 300 EFI, and my ballancer is pooched. The outer ring has spun on the hub about 120*. DOes anyone know of a manufacturer that makes solid dampers? what are the differences between a 289/302/351/400 ballancer and a 300 ballancer. or a 460ballancer for thaT matter. If they bolt on the same/ are the same blank, I can re index if need be, but I don't want the ballancer to sepparate again.

 

So the last balancer lasted 12 years? Some parts just get old and need to be replaced. I put a new one on my I6 for around 80 bucks. Slam dunk. Time is money. Thats my 2 cents worth. I think they last longer if they are not getting lubed from a leaking crank seal. You got a leaker?

 

no leaks, just "sweat" arount the filter and the tappett cover. According to the guy i bought the truck off of, it is the second ballancer since he had it, and someone else had it before him. As I plan on keeping this truck for a good long time, I'd rather just not dick around with it, and replace it with something good. Like when I replaced the Timing gear with an aluminum one, better than the stock Phenolic, but still weak enough to give out if there is a problem

 

All the balancers do look similar, but they are engine specific. Dorman makes decent balancers and they're only $70-$80. Pioneer makes them too but they're twice the price and I see no difference in quality between them. I've only seen stock dampers for the 300, not enough of a performance aftermarket for someone to be making a performance version.

An engine that "eats" dampers usually points at something amiss. Leaking oil breaking down the rubber is a big cause, but so can be over-tight belts or an accessory [alternator, ps pump, etc] with a bent shaft or pulley causing excess vibration.

As to the timing gears, the "softer" materials [fiber and aluminum] were used to reduce noise, not to act as a mechanical fuse. The timing gear is one of the last things you'd want giving out, because if the cam stops spinning in time with the crank then valves meet pistons and the motor is toast. I'd definitely get rid of the fiber cam gear... those things would make me nervous.

 

Im not sure but i don't think the pistons would kiss the valves if the gear went. The fiber gear is still junk though. With all the cast on the 300, they could have used some of that extra weight on metal gear. Mine probably looks like a deadly weapon.

 

I'm pretty sure the 300 is a non-interference motor - somebody correct me if I'm wrong?

 

Valve interference depends on the pistons. HD versions with the low compression [7.9-1, 8.0-1] wedge head pistons should be safe, as possibly would later models with -33cc D shaped recesses. Older and mid-year models with the odd round plug recess in the piston could be valve whackers. About to install new valve springs so I'll run a little test to see what the piston to valve clearance is.

Even if the valves don't contact the pistions there's still the problem of nasty backfire, esp. in carbed engines. The pistons are still pumping air and the carb feeding gas. You can wind up with an instant where the intake is wet with gas and you get detonation from one of the "open" cylinders. I've seen intakes cracked and carbs gutted by backfire after a timing chain let loose.

 

Thats interesting. 87-94 models are non interference stock, mabey even before, i believe. I cant wait to see what it looks like when my 300 throws a rod through the block, probably this year, or the next time i get pissed off at it. I will post the pictures on this site.