two pushrod tubes crushed inward when i started car

[john young]

1600cc single carb I think 1972 single port engine, two push-rod tubes crushed inward when i started car , this car had not been started for a year but was running. the fuel was old , so I took out the fuel tank and cleaned it out, then cleaned all fuel line , put new filters in line , BUT it still would not get fuel so took off the top of carb ,, at this time I realized that the float goodie (valve that moves up and down with the float , and allows the fuel to come in was stuck so that no fuel could come into the float bowl ,, I freed up the valve and the fuel could then go into the float bowl the fuel flowed and the engine started ,,, When it started it sounded like it was running on 3 maybe 2 cylinders ,, I turned it off thinking maybe a plug wire was off and noticed oil on the ground ,and two push-rod tubes crushed inward . my question ,,,, if i replace the tubes and probably bent push-rods MIGHT THIS PROBLEM HAPPEN AGAIN ?? Is there something else i should check or do before starting engine?

[john young]

[quote="john young"]

[john young]

[Marc]

The tubes are damaged because the pushrods bent. The pushrods bent because the valves were either stuck or they impacted a pile of corrosion detritus piled up atop the pistons - something's got to give.
I would advise that you remove the engine and BOTH cylinder heads to ensure that the top of the pistons are cleaned out, and dismantle the heads to check the condition of the valves and guides. You may also find a couple of cylinderwalls that are in poor shape...this is what happens when an engine gets put up with the rockers on, some of the valves will always be open allowing atmospheric moisture to enter the chambers.

If you feel lucky, remove the rockerarm assembly and sparkplugs, verify that the engine can be turned over by hand and then crank it with the plugs out to blow the worst of the junk out. Then rotate the crank to put the TDC mark up and bop both of the valves of #2 cylinder with a softer-than-steel mallet (strike the valve stem only, not the retainer or you could end up dislodging the keepers) to verify that they're free to move and not bent/stuck in the guides. Rotate the crank 'til the TDC mark is down and repeat for the #1 valves. If everything appears OK, reassemble replacing the bent pushrods (no need for pushrod tubes just yet) and again verify that the crank can be rotated by hand for a minimum of 2 full turns before you use the starter to crank it over for 5 or 10 seconds. If nothing breaks/bends, pull the rockerarms again and install a couple of "repair" expandable pushrod tubes before final reassembly, valve adjustment, and sparkplug installation. Be cautious on the latter since the plug threads in the head may have crud in them - if you have compressed air blow them out, if not squirt some WD-40 at them and crank on the starter some more.
I would adjust all of the valves somewhat loose (say, .008-.012") and let it run for a half-hour or so that way so they can hammer a little extra to (hopefully) clean enough of the rust away from the seats & faces that a good seal can be established. If you haven't already changed the oil that should happen before you run it - don't be surprised to find a little water from condensation present - as well as again within no more than a few hundred miles.

[john young]

thank you for your thoughtful answer to my question,,,, I will let you know what i find ,,, gratefully yours john