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Having issues with a 5.0 top end build.

Sean2857

New Member
Hey everyone. I recently did a top end build on my 1990 5.0 convertible. The build consists of gt40p heads, trick flow valve springs, E303 cam, and comp cams 1.7 roller rockers, stock push rods and Ford performance hydraulic roller lifters. When adjusting the rockers, I'm rotating the engine until the exhaust valve opens all the way and just starts to close. With the engine at this point, I adjust the intake valve to where I can spin the push rod with my fingers, then tighten a quarter turn more. I repeat this process for each cylinder. When I adjust them in this manner, it seems as though the valves are hanging open and the car won't start. Every adjustment procedure that I find, says to do it this way but just doesn't work. Does anyone have any tips or ideas on what I'm doing wrong? Attached is a photo of the type of rockers I'm using
 

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broncojunkie

Well-Known Member
My rockers are different than those. The adjustment isn't on the rocker stud itself, it's on the pushrod side with a lock nut.
They sure are. I didn't pay attention. I'm really rusty on the pedestal-style setup, since all my engines now have stud mount-style heads. Maybe one of the other guys will chime in with their experience.
 

Sean2857

New Member
They sure are. I didn't pay attention. I'm really rusty on the pedestal-style setup, since all my engines now have stud mount-style heads. Maybe one of the other guys will chime in with their experience.
I watched a video on comp cams YouTube channel that showed how to adjust them. The process was basically the same. Tighten the stud to 20ft lbs, adjust the rocker till the push rod spins free, then give another 1/4 turn to set preload. When I do this, the valves hang open and the car won't run. An 1/8th of turn after 0 lash is max. The rocker still feels really loose at this point and the push rod is still easily spun with my fingers. I had the car running pretty well at one point but it was hard to start when it was warm. I figured the valves were hung open due to the expansion of the valves when warmed up. I was wrong. I forgot to install the IAT sensor. Now I'm back to square one to try and adjust these things‍♂️♂️♂️♂️♂️
 

broncojunkie

Well-Known Member
My buddy had a similar problem on his 88gt (my old car) but his were stud mount. The problem came into play when he turned the adjustment nut down to set zero lash. Several of them would bleed off under very little pressure. It was my understanding that hydraulic lifters have a mechanical spring as well as the hydraulic pressure to counter the spring/cam lobe pressure. He was also using 1.7 rockers. In his case, the lifters were the original stock ones and a new set fixed him right up. I wonder if maybe you have a similar issue?
 

Sean2857

New Member
My buddy had a similar problem on his 88gt (my old car) but his were stud mount. The problem came into play when he turned the adjustment nut down to set zero lash. Several of them would bleed off under very little pressure. It was my understanding that hydraulic lifters have a mechanical spring as well as the hydraulic pressure to counter the spring/cam lobe pressure. He was also using 1.7 rockers. In his case, the lifters were the original stock ones and a new set fixed him right up. I wonder if maybe you have a similar issue?
Mine are brand new. I changed them out when I did the cam swap. I was going to reuse the old ones but figured it'd be a good idea just to replace them since I was there.
 

broncojunkie

Well-Known Member
Mine are brand new. I changed them out when I did the cam swap. I was going to reuse the old ones but figured it'd be a good idea just to replace them since I was there.
I saw that your lifters are new. I'm just wondering if they are collapsing prematurely, for whatever reason. I'm fairly certain most lifter manufacturers instruct you to set them up without "pumping them up" with oil. Maybe the 1.7 rockers put a little too much force on them when running them down by hand? If you could set them where it will run, let them pump up, and then readjust them to spec, that might do the trick. Just brainstorming here.
 

broncojunkie

Well-Known Member
I've also been following a guy on YouTube who has been looking into a rash of issues with new lifters. One of the common issues he found was that new lifters would bleed off too quickly, causing noise at startup. His old stock lifters would still hold pressure after months in storage, but the new ones would bleed off almost immediately. The flat tappet lifters had major issues, as well. They wiped out several new cams on break-in.
 

347HO

Active Member
You should always pre pump the system after installing new engine parts.
This also aids finding leaks if any.

Buy or fabricate a oil pump distributor shaft by welding an extension to it. Drive the pump using a high torque drill or 18v + cordless for 30 seconds.

Spin counterclock
 

347HO

Active Member
I also check each lifter oiling ports for debris.
Polish them.
Next time, buy EDM if you haven't already.

There are so many things I could write about all this crap... Not enough time or patience without specific questions.
 

Sean2857

New Member
I also check each lifter oiling ports for debris.
Polish them.
Next time, buy EDM if you haven't already.

There are so many things I could write about all this crap... Not enough time or patience without specific questions.
Thanks for the tips. I have an oil priming tool that I used before I initially started the vehicle. I'm using Ford performance OE style lifters.
 

347HO

Active Member
Suggest hitting it longer then.
You will see oil streaming from all the pushrods.
Many times, assembly lube takes a bit to move out of the way... When/if used.
 

Sean2857

New Member
Suggest hitting it longer then.
You will see oil streaming from all the pushrods.
Many times, assembly lube takes a bit to move out of the way... When/if used.
Wouldn't the engine have to be rotating in order to prime the lifters?
 

347HO

Active Member
Wouldn't the engine have to be rotating in order to prime the lifters?
Its been a while since seeing factory lifters in my hand... So here goes;

I believe factory lifters have the oiling hole located between the two bore rings and allows oil to feed in the full up and full down positions.

I've been running solid rollers for a long time and I may need correcting, but I'm fairly certain I'm correct.

So the answer to your question is "no".
However, I'd be proven wrong in the event anyone doing this does not see oil spurting from every pushrod at the rockers during priming.

Let me know.
 
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