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A pushrod from #7 is not in place. I don't know why I didn't see it before.... too busy taking things off, cleaning things and painting things. No wonder this cylinder only had 25 lbs of compression! Here in this pic you can see the top of the pushrod.
Is this an exhaust or intake valve?
What caused this? I know I won't be able to see any damage until I get the head off, but what damage could there be?
If the pushrod is damaged would I have to buy a whole set or just one?
Manufacturing defect. Extreme stress from a faulty spring(over long period of time), stuck valve, excessive RPM, lots of miles.......
......pick a reason.
Originally Posted by abe
but what damage could there be?
Possibly a damaged lifter, cam(probably not cam). If the spring or valve is partly to blame for the failure then you could have more there.
Originally Posted by abe
If the pushrod is damaged would I have to buy a whole set or just one?
Depends on where you get it. Used solid pushrods like that are generally durable and could be reused: try finding someone with a good strait unit to dispose of, shipping would be cheap.
Grab that pushrod with needle nose pliers and try pulling it out. It may just lift out unless it is bent too badly. Reason, who knows as expressed above. Damage, perhaps none. If the cam follower failed you have a big job ahead of you. At this point it makes no difference which valve it is. I think most used E II EE II E but some obscure Y blocks used different.
Edit: If you can't get pliers on it, try a loop of thin wire.
Are the lifters hollow like on the flatheads? if so it may have worn through, I had one that way. No damage except to the lifter and valve.
Probably explains the skip.....
Abe- mystery bolts? mystery push rods - what's next ??? (sorry I just conldn't resist inserting some humor -sick as it is)
Hopefully it's just the push rod and maybe the lifter at worst.
Should be an Intake as the two centers are Exhaust. Could have been any number of things including an over tightened Valve adjustment. Try to push down on the valve. If it moves get a different push rod and give it a try.
Abe- mystery bolts? mystery push rods - what's next ??? (sorry I just conldn't resist inserting some humor -sick as it is)
Hopefully it's just the push rod and maybe the lifter at worst.
There is one of the potential problems. The later Y blocks had captured lifters, meaning the cam rub surface was larger than the hole in the block in which the lifter fit. This mandated the removal of the cam to replace the lifter, not an easy job with the engine in place. I suspect the earlier Y blocks like Abe's are the same.
All y blocks have "mushroom " style lifters meaning the rub surface is larger than the the lifer bore and must be removed from the bottom side with the cam removed. I'd bet on a sticking valve. Also that's an intake valve
just noticed everything I just posted has already been mentioned. My bad
There is one of the potential problems. The later Y blocks had captured lifters, meaning the cam rub surface was larger than the hole in the block in which the lifter fit. This mandated the removal of the cam to replace the lifter, not an easy job with the engine in place. I suspect the earlier Y blocks like Abe's are the same.
I have no idea on these old engines so how can you tell if the lifter is damaged? Do you have to pull the cam? If you go that far wouldn't it be a good idea to redo all the bearings even if the lifter is OK? Again I have no idea on cost or amount of work involved. A good old 289 seems like a great idea and I know they are a lot easier to work on.
Abe - mushrooms can't be good for the engine - you are suppose to eat them.
Are the lifters hollow like on the flatheads? if so it may have worn through, I had one that way. No damage except to the lifter and valve.
Probably explains the skip.....
I have no idea on these old engines so how can you tell if the lifter is damaged? Do you have to pull the cam? If you go that far wouldn't it be a good idea to redo all the bearings even if the lifter is OK? Again I have no idea on cost or amount of work involved. A good old 289 seems like a great idea and I know they are a lot easier to work on.
Abe - mushrooms can't be good for the engine - you are suppose to eat them.
dial indicator to measure lift and that would tell you if the lifter or cam lobe has wear
With the heads off, I used a telescoping magnet to pull the lifters up and down to check for a sticking lifter. I think you can do this with just the valley cover off.
I just got out of the shower after coming in the garage. Wow! Thanks for all the responses and help.
I got the lifter out with a magnet. It came right out. To my eye it does not look bent at all. My Bil says it could have happened because of a backfire.
Anyways, I got the rocker arms off and called a buddy to help me lift off the heads. I don't know how one guy could do it himself. They are heavy and you are leaning over the fender and the fender adjustment for is in the way. So I am thinking it might be a stuck valve.
My BIL is coming g tomorrow morning to put on the new heads and adjust the valves. I don't think he'll stick around long enough to put everything back together so we can start the truck so I'll have to do that myself.
The push rods are solid.
I will post pics of what I've done tonight. Thanks all!
