Ongoing Battle With Hydraulic Lifters

I need help from the Ford gurus because my 1965 Mustang has officially become possessed.

The build:

• 1965 Mustang
• SN95 5.0 roller block
• Trick Flow 11R Top End Kit from TRE
• Holley Multi-Port EFI intake
• Holley Terminator X Max
• LU47 injectors
• T5 transmission
• Confirmed correct 7.050" pushrods
• More money than I care to admit
• Ford 9 inch
• Subframe connectors
• Mike Maier mod bar
• Coilover suspension
• Caltracks *up next*

So I install everything.
I carefully pump up the Trick Flow lifters (TFS-21400004-16) in oil by hand. They seem perfect, no issues with compression or feeling of them being stiff or stuck
I install them.
I prime the oiling system with a drill.
I fire the engine.
Success.
It runs.
Oil pressure is good. 45-50 cold and 30-35 at operating temperature.
No strange noises.
At this point I'm standing in the garage feeling like Carroll Shelby himself.
"Hell yeah. I nailed it."
Then the misfires begin.
Okay, maybe injectors.
Pulled all the LU47s and had them flow tested and they are perfect.
Okay, maybe ignition.
New performance distributor.
New cap.
New rotor.
New wires.
New plugs.
Still misfiring.
Now the weird part begins.
The cylinders that are misfiring seem to change.
One day it acts like one cylinder has a valve hanging open.
The next day that cylinder is fine and another one is dead.
So I tear the engine apart.
I discover three lifters that are pumped up completely solid.
Not stiff.
Not hard.
SOLID.
The plungers absolutely will not compress.
When resetting lash they literally hold the valves open.
No amount of finger pressure or vice with a v cutout and old pushrod cut to fit and compressed by spining the vice will move them.
So I disassemble the messed up lifters, clean them, reassemble them, compress them in oil, reinstall them, reset lash, ran a compression test showed 185-195 PSI on all 8.
And i thought i had won.....
Nope.
Different lifters start doing the same thing.
At this point I'm questioning every life decision that led me here.
So I decide the Trick Flow lifters must be bad and order brand-new Ford Racing M-6500-R302 hydraulic roller lifters.
The box arrives.
Several of the BRAND NEW lifters are already completely solid and impossible to compress right out of the package.
Now I'm standing in my garage holding brand-new lifters and asking questions like:

• What are they chances that two different hydraulic roller lifters actually be bad out of the box?
• Why do the affected cylinders seem to change?
• Why do some lifters become solid enough to hold valves open?
• Is there some oiling issue causing them to pump up and never bleed down?
• Is this normal and I'm just an idiot?
• Or has my Mustang become self-aware and decided to bankrupt me?

For reference:

• Trick Flow 11R Top End Kit
• Correct 7.050" pushrods confirmed
• Hydraulic roller cam
• Roller block
• Multiple lifters becoming solid
• Cylinders affected seem to change over time
• Injectors tested good
• Ignition components replaced
• Compression test was good

I'm not an experienced engine builder. I'm learning as I go and trying not to destroy this motor.

If you've seen hydraulic roller lifters repeatedly pump up solid and hold valves open after the engine warms up, please tell me where you'd start looking because I'm running out of ideas, money, and emotional stability.

Noobz347 said:

This by itself, is known to cause problems.


They should be soaked, not pumped up. That's an old-school trick that no longer applies.


I would wait for some other to chime in but every lifter you pumped up is a suspect. It is a known issue for hydraulic roller-lifters, at the very least. I do believe it also extends to modern flat-tappet lifters too.

Click to expand...

I understand what you're saying. I didn't pump the lifters completely solid before installation. I manually primed them in oil, but each lifter still had enough plunger travel to allow proper preload adjustment.

During installation, I verified that each lifter was on the base circle of the cam before setting preload. All of them accepted the recommended preload plus an additional 1/2 turn without holding the valves open. At that point, none of the lifters were acting solid or showing any signs of being over-pumped.

That said, given the issues I'm experiencing, I'm keeping an open mind before and will not compress the plunger in oil prior to installing the new lifters.

One thing that concerns me is that when I received the replacement lifters, I checked them out of the box and found that 4 of the 16 were completely solid. I could not compress the plunger at all with firm thumb pressure, while the others had at least some noticeable movement. My understanding is that hydraulic lifters should have some plunger travel available, especially when checking them by hand. Because of that, I'm questioning whether those lifters were functioning correctly from the start.

LILCBRA said:

Just so we're all on the same page, could you please describe your preload procedure? The 1/2 turn past should actually be your preload when installing adjustable roller rockers as sold in that kit. I'm assuming that it's this kit:

Trick Flow Ford 302 Twisted Wedge Top-End Engine Kit for 5.0L based engines TRE-TW-170-Top-End - TREperformance.com

The Racers Edge Performance - Trick Flow Twisted Wedge Top-End Engine Kit for Ford 5.0L offers new topend Kits for Small Block Ford at cheap discount wholesale prices.

treperformance.com

Click to expand...

Here is the kit that was purchased:

Preload procedure:
I would adjust the intake valve when the exhaust valve just starts to open.
Then adjust the exhaust valve when the intake valve is almost closed and on the backside of the lobe.

I set preload by first finding zero lash. To do this, I loosened the rocker while spinning the pushrod between my fingers, then slowly tightened the rocker until all vertical play was removed and the pushrod just started to show slight resistance while turning.

Then i tightened the rocker an additional 1/2 turn to set preload.

After verifying that all of the valves were adjusted on the base circle of the cam, I started the engine and it ran flawlessly. There was no valvetrain noise, no exhaust popping, and the engine idled and drove exactly as expected.

However, after a short drive and once the engine reached operating temperature, it began to hesitate and develop a noticeable shake. It felt like the engine was running on only five cylinders. When I got back home, I could hear valvetrain noise that hadn't been present at startup, and at that point I knew something had gone wrong.

Thanks for taking the time to respond. I appreciate the input.

LILCBRA said:

More or less the same kit for the purposes of the discussion. Sounds like you're setting them correctly, so we can rule that out. What kind of oil pressure does the engine have? Did the engine have any issues before installing all of this?

I wouldn't be horribly concerned about not being able to compress all of the plungers of the new lifters, they can and most likely will vary a little straight out of the box. I also wouldn't get too crazy about testing them out to make sure they move just to ensure that nothing gets messed up by doing so. Soaking them in an oil bath should be sufficient before installing them. The reasons that I'm aware of to do this is to make sure they're full of and coated by oil upon installation.

Click to expand...

Absolutely, what you linked was the same. The logs show 45-50 PSI of oil pressure when starting cold and when i pulled back into the garage it was at 30PSI on idle with coolant temps at 180.

The engine was 100% stock out of donor 1995 mustang with 74,000 miles. I installed the engine with minimal modifications last year and was able to drive the car all summer with no issues. Taking it on 300 mile road trips. Got surprising good gas mileage.

I also did a compression test with the 11r kit installed before driving and all cylinders showed 185psi +.

I will ignore the new stiff lifters and soak them overnight in oil before putting everything back together.

Thank you for all your help.