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Discussion Starter #1
I finally got around to taking down one of the 289's from one of the coupes and found a suprise, bent pushrods. The previous owner provided me a receipt for work done to the engine (five bent pushrods were replaced). The heads were rebuilt, new waterpump, hoses, carb, several lifters, fuel pump, gas tank cleaned and thermostat were also replaced as well.

When I bought the car it ran lit sh*t but I wanted it because it had so many options. The running condition didn't bother me until now.

I just want to know what are some of the causes for bent pushrods.

Thanks,
Ron
 

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Well I can think of 4 causes of bent pushrods.
1. REALLY bad valve geometry.. Not very likely if you have the right parts (rockers, pushrods, valves, spring retainers, cam). Look for contact of the rocker to the top valve spring retainer.
2. Too light a valve spring. Floated a valve and kissed a piston.
3. Too much lift/ duration. Kissed a piston.
4. Timing is way off so valves and pistons are trying to occupy the same space at the same time. I think that goes against one of the laws of physics. I doubt it would run at all if timing was that far off.
 

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Discussion Starter #5
I just pulled the valve covers off and just noticed that one of the pushrods was broken???

The engine has the stock A-code cam AND this problem happened before anybody even had the chance to tighten down the rocker arms on the newly installed push rods?????

Thanks,
Ron
 

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I put in "rebuilt" 289 in my first mustang back in 1993. The idiots at the builders installed the cam gear off by 5 teeth. Bent all intake pushrods, broke all rocker arms. Engine started briefly. What a MESS! I should have rebuilt the motor myself. I ended up pulling the heads 4 times to finally get other problems corrected.

Rob
 

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Take one 16 yr. old, add 3 Mountian Dews, one viewing of Smokey and the Bandit, 35 year old valvesprings, empty stretch of hiway = Bent pushrods
 
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