bent intake push rods 1988 straight 6

[captainron478]

bought a 1988 f-150 6 cly 300 was going to junk yard has not been ran in 3-4 years.changed fuel,filter,high volume pump and computer to get injector pulse ran for 30-40-minutes ran fine shut truck off next day would start but ran rough missing on 2nd cyl found push rod bent changed lifter and push rod ran good all 6 samething shut off next day rough really bad took side cover off found 2 bent rods and some off lifters all were on intake valves and ideal what could cause this or what is going on

[mcmalloy]

your injectors are probly leaking fuel into the cylenders as it sits ,

[captainron478]

what are my options for this besides new injectors due to expense of new ones

[RahX]

I would look at the injectors and make suree there is nothing getting into the cylinders. You might be looking at a sticky valves also.

[FNA]

Why would leaking fuel injectors cause bent push rods?

[RahX]

If the cylinder has a lot of fuel in it, the piston could hydrolock and keep the valve from opening. The weak link would most likely be the pushrod and it would bend.

[mechhound]

This doesn't totally fit in with your description of what happened, but I would suspect a sheared nylon composite cam timing gear. The 6 cylinder doesn't have a timing chain, just 2 gears that mesh together.

[FNA]

"If the cylinder has a lot of fuel in it, the piston could hydrolock and keep the valve from opening"

thanx for the response - but this engine started and ran per poster, so piston can't be locked. In such a case engine won't turn over, right? If any one piston isn't moving, none of the rest are either.

I tended to think cam timing myself - possible can run albeit poorly a tooth or two off.