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Discussion Starter #1
Hello again guys ,
still having issues with my engine .. (see past )
Last time i was back in home (portugal)and was able to spend time with my car i found by accident that my pushrods were slightly bend .. the engine hasn't been running fine apart from the first 10 mins when i got it (came from usa to europe) So i ordered the size pushrod that is in my engine and also a pushrod length test kit from summit. So today i had proper access to everything and i found out that when following the precudere to get to TDC by the rockers /intake exhaust valves that if i turn the flywheel/engine until intake has open and close and just as it opens cylinder 1 exhaust valve its nowhere close on my harmonic balancer to TDC also looking with a camara into the where the cylinder is ,its not even close to TDC when the exhaust valve on cylinder 1 is about to open. Checking with the camera inside the engine when the flywheel /harmonic balancer is on idc the piston in cylinder is really at its highest. What do base my TDC now on to take the proper measurement of the pushrods? Is the cam just very radical ? Has the guy who build the engine put the camshaft the wrong way?? Also what i have had in the past is that the engine had a timing completely out of this world .. almost like the distributor was off by one tooth..but today i could see when i was TDC and the piston was all the way up , the distributor was pointing to cylinder 1 properly . I'm guessing the camshaft has been installed wrong ?? or is that something somebody can explain?
 

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Hello
Sorry to read this engine is giving so much grief.
Looking at the picture of the damper this engine does not look fresh, from the deposits on the cover and block, so it must have a few miles on it. If the cam was not installed properly I doubt it would have run long, if at all.
Reading through your previous posts you said you have a TDC checking tool? Using that tool you can verify the timing marks on the damper.
Using valve events and the factory damper is confusing. Without a camshaft specification card and fully degreed damper it would be impossible to figure out. You would have to pull the damper and remove the timing cover to check the timing marks. I would not do that at this point
You will have to know, or determine if the cam is a hydraulic lifter or solid lifter. You will need that to properly set the valve lash.
Bent pushrods can be caused by;
  • Mechanical interference, piston to valve contact
  • Hydraulic lock, fluid in the cylinder
  • Weak / broken valve springs and the pushrod coming out of position
  • Failed cam lobe
How bent are the pushrods?
How many valves?
Pictures of bent pushrods?
Reading through your previous posts I did not see you performing a cranking compression test on this engine?
A compression test will tell you the internal condition of the valve and piston ring seal. The cylinders with bent pushrods are the big concern.
If you have removed the pushrods the engine can't be cranked for a compression test. So the pushrods will have to go back in to do this test, valve train must be functioning. Also during cranking the rocker arms can be observed for valve lift, comparison between cylinders.
Or if you have an air compressor you can remove both pushrods & air up the cylinder through the spark plug hole, (use the compression tester hose) and listen where the air is escaping from.
 

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If you are trying to find true TDC you cannot do it by looking in the cylinder,watching your rockers or watching your piston. The only way to find true top dead center is to take the head off and putting a piston stop across the cylinder or by putting a TDC tool into the #1 cylinder to make a piston stop. It really helps to have a degree wheel and a adjustable pointer of some kind. Put your piston stop in place and rotate the engine over until it hits the stop. Make a mark on the degree wheel and turn the engine over the other way until you again hit the piston stop. Make another mark on your degree wheel. At this point you will have two marks on your degree wheel. The exact middle between your two marks is TDC.
 

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Discussion Starter #6
so i finally got this TDC tool into my spark plug hole Cylinder nr1 and it looks like the TDC marking is correct with the balancer. So the question what happened to very slight bend a couple of pushrods could be from fowling i observed .
The rocker covers had some sort of edges inside ,which were touching the rockers arms for at least a couple of Revolution . The guy who put this engine together then obviously with a grinder took the edges off inside the rocker covers.Did that might broke also something else ?? See the pictures of the rocker cover and the rocker arms. Another one could be that the engine got so flooded from my faulty carburetor that in fact it might hydrolcked ??
What else should i check before installing the new Pushrods ? I'm thinking of sticking my little endoscope camera in there and see if it touches still ...and properly dremel a bit more off the edges .....
 

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Discussion Starter #10
just went with my camara into the intake to check if its hydraulic roller or flat tapped ...Can you guys tell by the pictures ??
 

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The edges are cast in oil drippers to help the stock rocker balls lubricate.
Yes it appears there was contact between the drippers & the exhaust rockers, are the exhaust rockers with marks the only pushrods that are bent? Or what other pushrods are bent?
You could grind the drippers smooth with the cover surface. A little ball of clay or putty on the contact area, put the covers on, roll the engine over two revolutions by hand, remove the covers and check the thickness of the clay = clearance.
Doing a cranking compression test will save time diagnosing the extent of damage. Low compression in a cylinder with bent pushrods will indicate bent valves. Using the old pushrods for the compression test is advisable so you don't damage you new parts.
If the compression is good, valve actuation is equal, and the only bent pushrods are from the rockers that made contact, the valve cover clearance should solve the issue.
Install the new pushrods, set the valve lash.
Read this for valve lash
The Basics of Setting and Adjusting Valve Lash
 
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Discussion Starter #15
ok i got my answer regarding question if mine is flat tappet or hydraulic roller...see the picture below
 

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Discussion Starter #17
sooo i just found something else ....that is on one of the rocker arms with a bend pushrod .....
 

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Discussion Starter #19
all the rocker arms with witch scratches on them have the same damage where the push rod runs.....:( can i still use them? There is no damage on the heads of the pushrods that are in the engine right now which tells me the old owner must have replaced the pushrods already once at least....
 

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The surprises keep coming
Have to ask what is your expectation for this engine? It is appearing more and more it was damaged and patched back together, and that hasn't worked.
If your determined to save it, and make it reliable, this could take allot of time, tools and $$
Knowing the heath of the engine will save throwing good $$ and time away
  • Compression test
  • Oil filter contamination
Sometimes we get to the point of yank it and have it rebuilt, the way you want it, then its reliable and you can enjoy the ride.

Rockers, if it was me, no I would not use them, the steel cup keeps the pushrod in place, if the pushrod tip gets out of place you will bend up more parts. Your decision.
They could be used for the compression test you are going to do? Remember fully assembled valve train. The pushrods in the picture are good enough for this test as well.
Those missing steel chunks went in your engine, get a magnet and check the top of the head and oil drain back areas, if no chunks they were cleaned up already or making their way to the oil pan somewhere. I would advise cutting the oil filter open and check for shinny bits.

For the lifter type, you are getting close to the answer. If you don't set it up properly all this work will be for nothing;
  • You have a flat tappet cam, not roller, but still could be hydraulic or solid lifter.
  • The hydraulic lifter pushrod seat is a piston, it can be compressed down into the lifter body. We call this preload.
  • The solid lifter is just that, solid and the pushrod seat will not compress down into the lifter body
  • Some manufactures of lifters use the same snap rings on top, so they may look the same.
Please take the time to read through the link I attached in the last message "The basics of adjusting valve lash", the topic is covered in there.
Don't mean to drag this point out, but its important to make it run properly.
 
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