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Got a question that hopefully someone can help me with in regards to valvetrain noise and hydraulic lifter problems. I'm also running 1.7 Crane Cobra roller rockers.
For about a year now, I have a prominent valvetrain rattle that comes and goes. It's far worse in winter, than summer. Well today, I thought I would once again remove the driver side valve cover and do some checking.
Well, I noticed that everything looks good. Engine has been sitting since 9am Friday morning. Plenty of time to indicate a problem since it happens a lot when the engine has sat.
1st. So I decide to give the "Push" test on all the roller rockers. All Pass.
2nd. I then bump start the several times over. Then stop. I start next "Push" test.
Results...
#6 Intake pushrod is able to rock back and forth quite a bit.
#7 Exhaust does, but not as bad as #6.
#8 Exhaust does a little.
All others on the driver side "Pass".
Now, can anyone tell me if that is the lifter that has failed/weak or pushrod problem. I went over this engine many times in March 2014 and verified with a solid lifter that I had my preload correct.
So a little more info after some more investigating.
After removing all but #8 rockers, I noticed that the pedestal mounts have cracks in the pivot stand. Nearly everyone has vertical cracking. I never saw this before, so, looks like I'm unto something.
I'm still unsure WHY #6 intake rocker had the most play after the engine was turned over once. Perhaps it was already near, on top, or just starting its descint down the cam lobe. I can't remember.
All have 0.020 shims in place. All the valves show a good CENTERED run. Just as it was when I set them up with my solid lifter.
What gives folks? I'm not finding a smoking gun yet. Will look into it further. I will also try to get pics of the cracks in the pedestal's.
The 1st pictures show the best of the worst. And it's prominent on Both not just one on each pedestal.
Edit: After completely removing the rocker and pedestal assembly from #8, its the worst with long cracks in each fulcrum stand.
I have spares from another engine that I am gonna use.
On another side note, I did some poking around. I found that if I fully depress the pushrod, with the rocker, I get near 0.090 with my feeler gauge between the valve tip and the roller. With my 0.020 shim removed, it is lessened to around 0.050. I'm taking it that my measurements weren't right and I didn't need the shims with stock pushrods. Go figure!
If I'm wrong, hopefully this long-winded post has explained it enough that someone with way more wisedom can help me out.
I just decided to once again, pull the lower intake and see what is going on.
Upon pulling #6 intake and Exhaust lifter, I found that the lifter plunger inside is solid and can't be pushed in with all my weight on it. But... What I didn't expect was that if I just barely touch the lifter cup, oil expels from the side oiling hole. Still though, the lifter plunger in the body does not go up or down. There is excessive up and down slop in the lifter cup to retainer. I believe I have certainly found the problem.
My solid lifter mock up was correct for preload. I can't fathom what the problem is with this set of lifters.
I haven't gone through the entire set yet, but will soon to verify my thoughts.
As of right now, I am in the process of completely tearing apart a NOS set of Motorcraft lifters and ensuring that each can work as promised.
It's a little late now to ask, but if you're taking apart new lifters, is it OK to mix each of the lifter plungers up? I using MMO and Acetone to clean each one, and it would have been nice to have all in the solution so I just have them all ready to install.
Was the engine block decked? Heads resurfaced? If so did you use custom length pushrods?
Thanks krooser for taking a moment for my post.
As far as I know, the engine block was never decked. History of this block is that it was Rebuilt by Ford in 1999. Bored 0.040 over. It's a 1990 block. I tore it down and replaced the cam and lifters. Had a machinist polish the crank and hone the cylinders.
My machinist milled maybe around 0.005-0.008,10. Who knows how much Ford shaved them in 1999.
I believe if my memory serves correctly, my pushrods were 0.028 to long. When I used my solid lifter mock up, if I shimed with 0.020, then it gave me 1/2 -3/4 turn past zero lash for preload @ 22 ft.lb.
If I didn't shim, then I was 1+ full turn past zero lash.
It was good to see more input from different minds and eye's!
The over torqued stands is what I believed happened. Though I have never exceeded 22 lbs. I will stick with 18 from this point on. I know its from 18-24, but this could have been there before hand, and I just never noticed it.
Maybe if the rain finally moves out of Missouri this week, I can have everything back together by Saturday.
06-27-2015, 09:46 AM
