Bottoming out a hydraulic lifter is not as easy as it sounds. I'ts done in racing and you need to know how your engine expansion (Head, Block) reacts when hot so you don't end up with an open valve. But for the quick purpose of checking the lifter oil functioning capabilities I suppose it would work. With that being said, it ran quiet with the bottomed out lifter correct? No issues. In that case it really could be that you had two stuck lifters. If you had access to another Crane lifter I would try it like you wanted to do. Without being able to get another one, and after inspecting the cam lobe, lifter bore and rocker arm if all looks good I would order a set of Morels.

Which cylinder are you having this lifter pump problem with? Is this the same cylinder that had the broken lifter originally or a different cylinder?

No. 6 cylinder, yes same cylinder. Removed broken lifter, installed used lifter that was not broken. Same tap noise. There is still a second lifter present in the engine that has a broken lip. It is not tapping. I worked with the broken lifter in no. 7 because I was able to fish out with a magnet and hook tool and reinstall different lifter through small passages is the head.

This noise really sounds like a lifter tap. As I tightened the valve adjuster, I was able to bleed out the hydraulics and bottom out the hydraulic lifter. I could see the spring start to compress, then back of the adjuster to essentially a solid lifter, then no tap, tap. I did not try to drive the car like this, only engine idle. I tried to remove the small snap-ring and disassemble the lifter. on tap-tap lifter. I could not get the plunger (hydraulic guts) out past the tie-bar rivet.

I meant no 6 cyl. not no. 7 above. I fished out the lifter pairs from both no. 6 and 7 cylinders. I tried swapping the tap-tap lifter from no. 6 with the lifter pair in no. 7 (not tapping) to see if the tap-tap followed, but was not able to fish the lifter back into no 7 lifter bores. Surgery lasted several hours over three nights. I tried different magnet and hook tools, wire and string to fish back in. I was not able to reinstall lifter in no. 7. Had to stop before violence!! Now dead in the water and need to pull the intake manifold to access lifters to move forward. As I mentioned, I plan to pull the motor. I think I will replace all lifters at this point. Will take Club Cobra forums advice and install Morels. I plan to call Rick over the phone to discuss. I still want to get to the bottom of breaking springs. A labor of love...you guys understand! Typing finger getting tired!! More later.

Having two lifters not pump up is certainly suspicious. The reason I ask about the cylinder location is that I might be worried about a blockage in the lifter oiling gallery. FE blocks have a lifter gallery that is fed from the back and runs to the front. I assume the Shelby block is the same even though the mains are a "priority oiling" system. Anyway, if the problem was in one of the two front cylinders, 1 or 5, then I would be suspicious of trash in an oil passage. But, if it was one of the middle cylinders, then a blockage in the gallery would *probably* prevent proper lifter function in all cylinders forward of the problem. Not sure, but that seems likely. If the lifters forward of your problem cylinder seem to be working, then I'd guess that the oil passages are ok. Still, two lifters not pumping up is odd. The problem I've always had with hydraulic rollers is them not bleeding down.

As far as taking them apart, you rightly state that you need to remove the tie-bar rivet. It's worth the effort if you're at all curious.

I think it's time to pull the motor, sorry to say. I feel for you. Interior, trans tunnel, and that stupid riveted panel under the dash...it sucks.

If you pull the trans with the engine (that's my preference), don't forget to track down one of those rubber shipping plugs that fits in the output of the TKO...you don't need trans fluid everywhere, adding injury to insult.

Chin up, this is the fun part of owning a cobra:rolleyes:

OK guys, Back to possible reasons why my FE Edelbrock head inner valve springs were failing. I have removed the engine and have more valve-train data for evaluation. Each valve has Dual Springs: Here is data I measured for springs installed in my engine:

Large Spring (Uninstalled Physical Measurements)
O.D Inches 1.51
Wire Dia. Inches 0.196
I.D. Inches 1.118
Height (no Load) Inches 2.42

Small Spring (Uninstalled Physical Measurements)
O.D Inches 1.1
Wire Dia. Inches 0.156
I.D. Inches 0.788
Height (no Load) Inches 1.94

I measured the actual valve stroke on the engine using a dial indicator & calipers and determined the following:
Assembled heights (bottom of spring to top of spring): 1.93-1.94”
Valve stroke (dial indicator on spring retainer): Intake: 0.437, Exhaust: 0.424.
Therefore : Spring height with valve full open:
Intake: 1.935-0.437= 1.498”
Exhaust: 1.935-0.424= 1.510”
Coil Bind (Engine Build data) 0.825. I inspected springs at full stroke and visually confirmed the springs are not close to coil bind.
Spring Pressures Engine shop data from spec sheet):
385 lbs @ 0.500
415 lbs @ 0.550
435 lbs @ 0.600
445 lbs @ 0.620
460 lbs @ 0.650
Using some curve fitting data and calculations, the spring force at compressed spring height of 1.51” is 448 lbs spring return force (approx).

Is 450 lbs a lot? Anything striking?

You can't measure valve lift at the retainer like that. The lifter is going to compress and you lose probably .100" of lift. I know you have more than .437" of valve lift.....

Yes, that's too much spring pressure for a street hydraulic roller.

Agree.

List your camshaft specs, and your rocker ratio.

Have you inspected the cam lobes with the suspect lifters out?

It's a Comp Cams 33-000-9 which probably doesn't help. I can provide the grind card if more info is required.

Gross Valve Lift: Intake: 0.645", Exhaust, 0.635"

Erson Lifters 1.76 ratio

Lob Lift: Intake 0.3670" Exhaust: 0.3610"

Intake 0.367" * 1.76= 0.645"

Exhaust 0.361" * 1.76= 0.635"

That seems to be the right calc since the result equals the gross valve lift. This cam must have been ground for 1.76 ratio rockers?

So now you see as Blykins says, you can't measure valve lift at the retainer with a hydraulic lifter.

Your 33-000-9 is a custom ground race billet.

262 @ .050 is a not a baby cam.

Here's some info from another forum thread:

This is the Comp Cam that's going in my 457FE:
Camshaft: Comp Cams custom grind 33-000-9
Intake Exhaust
Valve Adjustment HYD HYD
Gross Valve Lift .659 .659
Duration @
.006 Tappet lift 317 317
Valve Timing Open Close
@ .050 INT: 23 BTDC 59 ABDC
EXH: 59 BBDC 23 ATDC
These specs are for cam installed
@ 108.0 Intake Center line
Intake Exhaust
Duration @ .050 262 262
Lobe lift .3810 .3810
Lobe separation 108.0

My next question is do you have the valve springs off to measure them or have you got that info from elsewhere?

Does the outside of inner spring touch the inside of the outer spring? Helps to combat spring surge.

From what I understand, lifters "break-in" by developing a unique wear pattern in concert with the camshaft....however, my experience with roller lifters is limited, so if that is not the case with rollers the rest of my post will be just plain wrong....:confused:

Before the days of roller lifters, if you took all of your lifters out and didn't keep track of which lifter bore they came from so that you could replace EVERY lifter on the same camshaft lobe from which it came, you ran a risk of wiping the cam lobes out. The lifters don't have to be bad (per your Q about replacing a bad lifter with another bad lifter), they just have to be different USED lifters going onto a lobe for which they were not broken in.

Re-using used lifters is just not a good risk...a friend who did "shade tree" mechanic work in his driveway replaced the cam in a BBC once and against my advice to get new lifters he just put the used lifters back in...wiped all the lobes off in a very short time and had to replace the cam AND the lifters again.

That's where I'd start...get that cam out of there and mic the lobes to see if you've wiped out enough lift that the valve-train has developed enough clearance that the lifter is separating from the cam lobe as the engine runs (the tapping noise may be the lifter's roller regaining contact with the lobe of the cam).

As much as I hate to say it, you might need not only new lifters, but also a new cam...that is, unless roller lifters don't "wear in" to a cam lobe like the older style lifters did...which is a distinct possibility, given the "old school" nature of my mechanical experience.

I'm hoping I'm wrong....:rolleyes:

Cheers!

Dugly :cool: