|
By Dan - 16 Years Ago
|
|
Student had his 292 on the test and developed a bad miss, missed at the exact same time as the engine was running. Checked out some ignition stuff and it all looked so decided to look at the valves. Found one pushrod that was WAY down in the head almost like it had broken or come off the lifter? What caused this, what are we going to find when we pull off the intake and valley cover??? Thanks-
|
|
By charliemccraney - 16 Years Ago
|
You might be able to retrieve the pushrod with a strategically bent piece of coat hanger. I keep one of these specialty tools in my tool box.
I think the lash may have been too loose and the pushrod popped off. Or, if using the self locking screw it is no longer self locking. If that's the case, it's not a big deal.
Worst case, the cam lobe is going flat. Slightly better case, the lifter is wearing. Push rod could have broke.
|
|
By MoonShadow - 16 Years Ago
|
|
You can try just putting in another push rod and adjusting it. There are a lot of old Y's around with "extra" push rods in the valley! Not much there they can hurt. Also make sure all the push rods are the same length. There are two styles! Chuck in NH
|
|
By pcmenten - 16 Years Ago
|
|
If a valve hangs, wouldn't that cause the pushrod to come out? So his valves are sticking?
|
|
By MoonShadow - 16 Years Ago
|
|
Definately possible but putting in another one and cranking the engine will tell you real quick if it's a stuck valve. Then we can go from there! Sometimes a whack or two with a hammer and some oil will free them up. Chuck in NH I always go for the short test before a tear down (Columbus experiences aside:cool
|
|
By Ted - 16 Years Ago
|
|
Assuming it’s not a stuck valve, the pushrod may not have been squarely seated in the lifter when originally installed and just popped out when the engine was fired up. If the pushrod that’s missing is from an exhaust valve on cylinders 1, 4, 5, or 8, then look at the length of the bolts holding the intake down at the front or the two short bolts at the rear intake face of the heads in that they are not too long and are simply contacting the pushrods for those cylinders. Improper initial adjustment could have also been the culprit.
|
|
By Hawk5619 - 16 Years Ago
|
|
I agree with Chuck When I bought my 59 Edsel I got a good price because it had a miss in the motor. I pulled the valve cover and saw no pushrod for the #5 intake valve. I got out a flashlight and looking down the oil breather hole where you add oil I can see the broke pushrod laying in the valley. After trying magnets and other hand made tools I still can not get it turned the right way to get it out. I just put a new pushrod in there and after adjusting it and the other valves for the correct lash it runs just fine. Yes I should pull the manifold and get it out but I am building a fresh 292 to make it into the Hot Rod Edsel! I have put about 3K miles on that engine with that broke pushrod laying in the valley and if something real bad happens it will just speed up the new y block build! Rick Wellington, Colorado
|
|
By HT32BSX115 - 16 Years Ago
|
Also look very carefully at the pushrods that can come in contact with the intake manifold bolts. There's 8 bolt holes that will allow a bolt to come in contact with a pushrod if it's long enough with not so good results!
Cheers,
Rick
|
|
By Dan - 16 Years Ago
|
|
Well, good news??? Sounds like the pushrod just came off the lifter. Student wasnt able to fish it out so he pulled the intake and valley cover off and put it back together, sounds much better now (well, still needs some tuning but its running pretty good anyhow) still curious as to why it came off though? I suspect the valve lash and trying to reuse so many old worn parts might be equal contributors. His plans for the engine are to put it in an old Willys p/u, that should be kinda fun to figure out, we'll let you guys know how that goes. Thanks for the help with the pushrod problem!
|
|
By GREENBIRD56 - 16 Years Ago
|
|
Dan - Maybe I missed it but I didn't see a single question in this thread about "which pushrods?" are in the 292 that your student had the problem with. Is it the "solid bar" - and rather slender early pushrod - or the tubular style from later on? The 5/16 diameter tubular type were used on the later model engines - after '57 maybe - someone here will know for sure. The tubulars have about three (or more) times the compressive column strength of the bar style. The skinnies worked OK in my engine - until I started to hop it up a bit and it would accelerate / rev much more quickly than before. When I finally got a decent carb on it and a good tune - it instantly "ate" three old style pushrods. I must have had marginal lubrication on the stems and guides - and the increased "rev rate" pushed it over the edge.
|
|
By crab - 16 Years Ago
|
|
Had the same thing happen recently, the car sat for the last 15 years. Found a stuck valve, bent pushrod and one off track, now I'm looking for some heads.
|